diff --git a/desktop/src/main.ts b/desktop/src/main.ts
index 8526e2363..467d9c881 100644
--- a/desktop/src/main.ts
+++ b/desktop/src/main.ts
@@ -24,9 +24,10 @@ import { attachFSWatchIPCHandlers, attachIPCHandlers } from "./main/ipc";
 import log, { initLogging } from "./main/log";
 import { createApplicationMenu, createTrayContextMenu } from "./main/menu";
 import { setupAutoUpdater } from "./main/services/app-update";
-import autoLauncher from "./main/services/autoLauncher";
-import { initWatcher } from "./main/services/chokidar";
+import autoLauncher from "./main/services/auto-launcher";
+import { createWatcher } from "./main/services/watch";
 import { userPreferences } from "./main/stores/user-preferences";
+import { migrateLegacyWatchStoreIfNeeded } from "./main/stores/watch";
 import { registerStreamProtocol } from "./main/stream";
 import { isDev } from "./main/util";
 
@@ -196,8 +197,6 @@ const createMainWindow = async () => {
         window.maximize();
     }
 
-    window.loadURL(rendererURL);
-
     // Open the DevTools automatically when running in dev mode
     if (isDev) window.webContents.openDevTools();
 
@@ -296,6 +295,21 @@ const deleteLegacyDiskCacheDirIfExists = async () => {
     }
 };
 
+/**
+ * Older versions of our app used to keep a keys.json. It is not needed anymore,
+ * remove it if it exists.
+ *
+ * This code was added March 2024, and can be removed after some time once most
+ * people have upgraded to newer versions.
+ */
+const deleteLegacyKeysStoreIfExists = async () => {
+    const keysStore = path.join(app.getPath("userData"), "keys.json");
+    if (existsSync(keysStore)) {
+        log.info(`Removing legacy keys store at ${keysStore}`);
+        await fs.rm(keysStore);
+    }
+};
+
 const main = () => {
     const gotTheLock = app.requestSingleInstanceLock();
     if (!gotTheLock) {
@@ -311,6 +325,7 @@ const main = () => {
     setupRendererServer();
     registerPrivilegedSchemes();
     increaseDiskCache();
+    migrateLegacyWatchStoreIfNeeded();
 
     app.on("second-instance", () => {
         // Someone tried to run a second instance, we should focus our window.
@@ -325,19 +340,26 @@ const main = () => {
     //
     // Note that some Electron APIs can only be used after this event occurs.
     app.on("ready", async () => {
+        // Create window and prepare for renderer
         mainWindow = await createMainWindow();
-        Menu.setApplicationMenu(await createApplicationMenu(mainWindow));
-        setupTrayItem(mainWindow);
         attachIPCHandlers();
-        attachFSWatchIPCHandlers(initWatcher(mainWindow));
+        attachFSWatchIPCHandlers(createWatcher(mainWindow));
         registerStreamProtocol();
-        if (!isDev) setupAutoUpdater(mainWindow);
         handleDownloads(mainWindow);
         handleExternalLinks(mainWindow);
         addAllowOriginHeader(mainWindow);
 
+        // Start loading the renderer
+        mainWindow.loadURL(rendererURL);
+
+        // Continue on with the rest of the startup sequence
+        Menu.setApplicationMenu(await createApplicationMenu(mainWindow));
+        setupTrayItem(mainWindow);
+        if (!isDev) setupAutoUpdater(mainWindow);
+
         try {
             deleteLegacyDiskCacheDirIfExists();
+            deleteLegacyKeysStoreIfExists();
         } catch (e) {
             // Log but otherwise ignore errors during non-critical startup
             // actions.
diff --git a/desktop/src/main/fs.ts b/desktop/src/main/fs.ts
index 36de710c3..2428d3a80 100644
--- a/desktop/src/main/fs.ts
+++ b/desktop/src/main/fs.ts
@@ -22,10 +22,8 @@ export const fsReadTextFile = async (filePath: string) =>
 export const fsWriteFile = (path: string, contents: string) =>
     fs.writeFile(path, contents);
 
-/* TODO: Audit below this  */
-
-export const isFolder = async (dirPath: string) => {
+export const fsIsDir = async (dirPath: string) => {
     if (!existsSync(dirPath)) return false;
-    const stats = await fs.stat(dirPath);
-    return stats.isDirectory();
+    const stat = await fs.stat(dirPath);
+    return stat.isDirectory();
 };
diff --git a/desktop/src/main/ipc.ts b/desktop/src/main/ipc.ts
index a5de4514f..eab2e8b59 100644
--- a/desktop/src/main/ipc.ts
+++ b/desktop/src/main/ipc.ts
@@ -10,7 +10,12 @@
 
 import type { FSWatcher } from "chokidar";
 import { ipcMain } from "electron/main";
-import type { ElectronFile, FILE_PATH_TYPE, FolderWatch } from "../types/ipc";
+import type {
+    CollectionMapping,
+    ElectronFile,
+    FolderWatch,
+    PendingUploads,
+} from "../types/ipc";
 import {
     selectDirectory,
     showUploadDirsDialog,
@@ -19,13 +24,13 @@ import {
 } from "./dialogs";
 import {
     fsExists,
+    fsIsDir,
     fsMkdirIfNeeded,
     fsReadTextFile,
     fsRename,
     fsRm,
     fsRmdir,
     fsWriteFile,
-    isFolder,
 } from "./fs";
 import { logToDisk } from "./log";
 import {
@@ -49,16 +54,17 @@ import {
 } from "./services/store";
 import {
     getElectronFilesFromGoogleZip,
-    getPendingUploads,
-    setToUploadCollection,
-    setToUploadFiles,
+    pendingUploads,
+    setPendingUploadCollection,
+    setPendingUploadFiles,
 } from "./services/upload";
 import {
-    addWatchMapping,
-    getWatchMappings,
-    removeWatchMapping,
-    updateWatchMappingIgnoredFiles,
-    updateWatchMappingSyncedFiles,
+    watchAdd,
+    watchFindFiles,
+    watchGet,
+    watchRemove,
+    watchUpdateIgnoredFiles,
+    watchUpdateSyncedFiles,
 } from "./services/watch";
 import { openDirectory, openLogDirectory } from "./util";
 
@@ -132,6 +138,8 @@ export const attachIPCHandlers = () => {
         fsWriteFile(path, contents),
     );
 
+    ipcMain.handle("fsIsDir", (_, dirPath: string) => fsIsDir(dirPath));
+
     // - Conversion
 
     ipcMain.handle("convertToJPEG", (_, fileData, filename) =>
@@ -183,28 +191,26 @@ export const attachIPCHandlers = () => {
 
     ipcMain.handle("showUploadZipDialog", () => showUploadZipDialog());
 
-    // - FS Legacy
-
-    ipcMain.handle("isFolder", (_, dirPath: string) => isFolder(dirPath));
-
     // - Upload
 
-    ipcMain.handle("getPendingUploads", () => getPendingUploads());
+    ipcMain.handle("pendingUploads", () => pendingUploads());
+
+    ipcMain.handle("setPendingUploadCollection", (_, collectionName: string) =>
+        setPendingUploadCollection(collectionName),
+    );
 
     ipcMain.handle(
-        "setToUploadFiles",
-        (_, type: FILE_PATH_TYPE, filePaths: string[]) =>
-            setToUploadFiles(type, filePaths),
+        "setPendingUploadFiles",
+        (_, type: PendingUploads["type"], filePaths: string[]) =>
+            setPendingUploadFiles(type, filePaths),
     );
 
+    // -
+
     ipcMain.handle("getElectronFilesFromGoogleZip", (_, filePath: string) =>
         getElectronFilesFromGoogleZip(filePath),
     );
 
-    ipcMain.handle("setToUploadCollection", (_, collectionName: string) =>
-        setToUploadCollection(collectionName),
-    );
-
     ipcMain.handle("getDirFiles", (_, dirPath: string) => getDirFiles(dirPath));
 };
 
@@ -213,42 +219,36 @@ export const attachIPCHandlers = () => {
  * watch folder functionality.
  *
  * It gets passed a {@link FSWatcher} instance which it can then forward to the
- * actual handlers.
+ * actual handlers if they need access to it to do their thing.
  */
 export const attachFSWatchIPCHandlers = (watcher: FSWatcher) => {
     // - Watch
 
-    ipcMain.handle(
-        "addWatchMapping",
-        (
-            _,
-            collectionName: string,
-            folderPath: string,
-            uploadStrategy: number,
-        ) =>
-            addWatchMapping(
-                watcher,
-                collectionName,
-                folderPath,
-                uploadStrategy,
-            ),
-    );
-
-    ipcMain.handle("removeWatchMapping", (_, folderPath: string) =>
-        removeWatchMapping(watcher, folderPath),
-    );
-
-    ipcMain.handle("getWatchMappings", () => getWatchMappings());
+    ipcMain.handle("watchGet", () => watchGet(watcher));
 
     ipcMain.handle(
-        "updateWatchMappingSyncedFiles",
-        (_, folderPath: string, files: FolderWatch["syncedFiles"]) =>
-            updateWatchMappingSyncedFiles(folderPath, files),
+        "watchAdd",
+        (_, folderPath: string, collectionMapping: CollectionMapping) =>
+            watchAdd(watcher, folderPath, collectionMapping),
+    );
+
+    ipcMain.handle("watchRemove", (_, folderPath: string) =>
+        watchRemove(watcher, folderPath),
     );
 
     ipcMain.handle(
-        "updateWatchMappingIgnoredFiles",
-        (_, folderPath: string, files: FolderWatch["ignoredFiles"]) =>
-            updateWatchMappingIgnoredFiles(folderPath, files),
+        "watchUpdateSyncedFiles",
+        (_, syncedFiles: FolderWatch["syncedFiles"], folderPath: string) =>
+            watchUpdateSyncedFiles(syncedFiles, folderPath),
+    );
+
+    ipcMain.handle(
+        "watchUpdateIgnoredFiles",
+        (_, ignoredFiles: FolderWatch["ignoredFiles"], folderPath: string) =>
+            watchUpdateIgnoredFiles(ignoredFiles, folderPath),
+    );
+
+    ipcMain.handle("watchFindFiles", (_, folderPath: string) =>
+        watchFindFiles(folderPath),
     );
 };
diff --git a/desktop/src/main/menu.ts b/desktop/src/main/menu.ts
index 3441f3f2a..bd8810428 100644
--- a/desktop/src/main/menu.ts
+++ b/desktop/src/main/menu.ts
@@ -7,7 +7,7 @@ import {
 } from "electron";
 import { allowWindowClose } from "../main";
 import { forceCheckForAppUpdates } from "./services/app-update";
-import autoLauncher from "./services/autoLauncher";
+import autoLauncher from "./services/auto-launcher";
 import { userPreferences } from "./stores/user-preferences";
 import { openLogDirectory } from "./util";
 
diff --git a/desktop/src/main/platform.ts b/desktop/src/main/platform.ts
deleted file mode 100644
index 1c3bb4584..000000000
--- a/desktop/src/main/platform.ts
+++ /dev/null
@@ -1,19 +0,0 @@
-export function isPlatform(platform: "mac" | "windows" | "linux") {
-    return getPlatform() === platform;
-}
-
-export function getPlatform(): "mac" | "windows" | "linux" {
-    switch (process.platform) {
-        case "aix":
-        case "freebsd":
-        case "linux":
-        case "openbsd":
-        case "android":
-            return "linux";
-        case "darwin":
-        case "sunos":
-            return "mac";
-        case "win32":
-            return "windows";
-    }
-}
diff --git a/desktop/src/main/services/app-update.ts b/desktop/src/main/services/app-update.ts
index b47448501..a3f4d3bed 100644
--- a/desktop/src/main/services/app-update.ts
+++ b/desktop/src/main/services/app-update.ts
@@ -1,9 +1,9 @@
 import { compareVersions } from "compare-versions";
-import { app, BrowserWindow } from "electron";
 import { default as electronLog } from "electron-log";
 import { autoUpdater } from "electron-updater";
+import { app, BrowserWindow } from "electron/main";
 import { allowWindowClose } from "../../main";
-import { AppUpdateInfo } from "../../types/ipc";
+import { AppUpdate } from "../../types/ipc";
 import log from "../log";
 import { userPreferences } from "../stores/user-preferences";
 
@@ -52,8 +52,8 @@ const checkForUpdatesAndNotify = async (mainWindow: BrowserWindow) => {
         return;
     }
 
-    const showUpdateDialog = (updateInfo: AppUpdateInfo) =>
-        mainWindow.webContents.send("appUpdateAvailable", updateInfo);
+    const showUpdateDialog = (update: AppUpdate) =>
+        mainWindow.webContents.send("appUpdateAvailable", update);
 
     log.debug(() => "Attempting auto update");
     autoUpdater.downloadUpdate();
diff --git a/desktop/src/main/services/auto-launcher.ts b/desktop/src/main/services/auto-launcher.ts
new file mode 100644
index 000000000..c704f7399
--- /dev/null
+++ b/desktop/src/main/services/auto-launcher.ts
@@ -0,0 +1,51 @@
+import AutoLaunch from "auto-launch";
+import { app } from "electron/main";
+
+class AutoLauncher {
+    /**
+     * This property will be set and used on Linux and Windows. On macOS,
+     * there's a separate API
+     */
+    private autoLaunch?: AutoLaunch;
+
+    constructor() {
+        if (process.platform != "darwin") {
+            this.autoLaunch = new AutoLaunch({
+                name: "ente",
+                isHidden: true,
+            });
+        }
+    }
+
+    async isEnabled() {
+        const autoLaunch = this.autoLaunch;
+        if (autoLaunch) {
+            return await autoLaunch.isEnabled();
+        } else {
+            return app.getLoginItemSettings().openAtLogin;
+        }
+    }
+
+    async toggleAutoLaunch() {
+        const isEnabled = await this.isEnabled();
+        const autoLaunch = this.autoLaunch;
+        if (autoLaunch) {
+            if (isEnabled) await autoLaunch.disable();
+            else await autoLaunch.enable();
+        } else {
+            if (isEnabled) app.setLoginItemSettings({ openAtLogin: false });
+            else app.setLoginItemSettings({ openAtLogin: true });
+        }
+    }
+
+    async wasAutoLaunched() {
+        if (this.autoLaunch) {
+            return app.commandLine.hasSwitch("hidden");
+        } else {
+            // TODO(MR): This apparently doesn't work anymore.
+            return app.getLoginItemSettings().wasOpenedAtLogin;
+        }
+    }
+}
+
+export default new AutoLauncher();
diff --git a/desktop/src/main/services/autoLauncher.ts b/desktop/src/main/services/autoLauncher.ts
deleted file mode 100644
index 614c151ba..000000000
--- a/desktop/src/main/services/autoLauncher.ts
+++ /dev/null
@@ -1,41 +0,0 @@
-import { AutoLauncherClient } from "../../types/main";
-import { isPlatform } from "../platform";
-import linuxAndWinAutoLauncher from "./autoLauncherClients/linuxAndWinAutoLauncher";
-import macAutoLauncher from "./autoLauncherClients/macAutoLauncher";
-
-class AutoLauncher {
-    private client: AutoLauncherClient;
-    async init() {
-        if (isPlatform("linux") || isPlatform("windows")) {
-            this.client = linuxAndWinAutoLauncher;
-        } else {
-            this.client = macAutoLauncher;
-        }
-        // migrate old auto launch settings for windows from mac auto launcher to linux and windows auto launcher
-        if (isPlatform("windows") && (await macAutoLauncher.isEnabled())) {
-            await macAutoLauncher.toggleAutoLaunch();
-            await linuxAndWinAutoLauncher.toggleAutoLaunch();
-        }
-    }
-    async isEnabled() {
-        if (!this.client) {
-            await this.init();
-        }
-        return await this.client.isEnabled();
-    }
-    async toggleAutoLaunch() {
-        if (!this.client) {
-            await this.init();
-        }
-        await this.client.toggleAutoLaunch();
-    }
-
-    async wasAutoLaunched() {
-        if (!this.client) {
-            await this.init();
-        }
-        return this.client.wasAutoLaunched();
-    }
-}
-
-export default new AutoLauncher();
diff --git a/desktop/src/main/services/autoLauncherClients/linuxAndWinAutoLauncher.ts b/desktop/src/main/services/autoLauncherClients/linuxAndWinAutoLauncher.ts
deleted file mode 100644
index 0d2c1bb42..000000000
--- a/desktop/src/main/services/autoLauncherClients/linuxAndWinAutoLauncher.ts
+++ /dev/null
@@ -1,39 +0,0 @@
-import AutoLaunch from "auto-launch";
-import { app } from "electron";
-import { AutoLauncherClient } from "../../../types/main";
-
-const LAUNCHED_AS_HIDDEN_FLAG = "hidden";
-
-class LinuxAndWinAutoLauncher implements AutoLauncherClient {
-    private instance: AutoLaunch;
-    constructor() {
-        const autoLauncher = new AutoLaunch({
-            name: "ente",
-            isHidden: true,
-        });
-        this.instance = autoLauncher;
-    }
-    async isEnabled() {
-        return await this.instance.isEnabled();
-    }
-    async toggleAutoLaunch() {
-        if (await this.isEnabled()) {
-            await this.disableAutoLaunch();
-        } else {
-            await this.enableAutoLaunch();
-        }
-    }
-
-    async wasAutoLaunched() {
-        return app.commandLine.hasSwitch(LAUNCHED_AS_HIDDEN_FLAG);
-    }
-
-    private async disableAutoLaunch() {
-        await this.instance.disable();
-    }
-    private async enableAutoLaunch() {
-        await this.instance.enable();
-    }
-}
-
-export default new LinuxAndWinAutoLauncher();
diff --git a/desktop/src/main/services/autoLauncherClients/macAutoLauncher.ts b/desktop/src/main/services/autoLauncherClients/macAutoLauncher.ts
deleted file mode 100644
index 00320e870..000000000
--- a/desktop/src/main/services/autoLauncherClients/macAutoLauncher.ts
+++ /dev/null
@@ -1,28 +0,0 @@
-import { app } from "electron";
-import { AutoLauncherClient } from "../../../types/main";
-
-class MacAutoLauncher implements AutoLauncherClient {
-    async isEnabled() {
-        return app.getLoginItemSettings().openAtLogin;
-    }
-    async toggleAutoLaunch() {
-        if (await this.isEnabled()) {
-            this.disableAutoLaunch();
-        } else {
-            this.enableAutoLaunch();
-        }
-    }
-
-    async wasAutoLaunched() {
-        return app.getLoginItemSettings().wasOpenedAtLogin;
-    }
-
-    private disableAutoLaunch() {
-        app.setLoginItemSettings({ openAtLogin: false });
-    }
-    private enableAutoLaunch() {
-        app.setLoginItemSettings({ openAtLogin: true });
-    }
-}
-
-export default new MacAutoLauncher();
diff --git a/desktop/src/main/services/chokidar.ts b/desktop/src/main/services/chokidar.ts
deleted file mode 100644
index 5d7284d2a..000000000
--- a/desktop/src/main/services/chokidar.ts
+++ /dev/null
@@ -1,45 +0,0 @@
-import chokidar from "chokidar";
-import { BrowserWindow } from "electron";
-import path from "path";
-import log from "../log";
-import { getElectronFile } from "./fs";
-import { getWatchMappings } from "./watch";
-
-/**
- * Convert a file system {@link filePath} that uses the local system specific
- * path separators into a path that uses POSIX file separators.
- */
-const normalizeToPOSIX = (filePath: string) =>
-    filePath.split(path.sep).join(path.posix.sep);
-
-export function initWatcher(mainWindow: BrowserWindow) {
-    const mappings = getWatchMappings();
-    const folderPaths = mappings.map((mapping) => {
-        return mapping.folderPath;
-    });
-
-    const watcher = chokidar.watch(folderPaths, {
-        awaitWriteFinish: true,
-    });
-    watcher
-        .on("add", async (path) => {
-            mainWindow.webContents.send(
-                "watch-add",
-                await getElectronFile(normalizeToPOSIX(path)),
-            );
-        })
-        .on("unlink", (path) => {
-            mainWindow.webContents.send("watch-unlink", normalizeToPOSIX(path));
-        })
-        .on("unlinkDir", (path) => {
-            mainWindow.webContents.send(
-                "watch-unlink-dir",
-                normalizeToPOSIX(path),
-            );
-        })
-        .on("error", (error) => {
-            log.error("Error while watching files", error);
-        });
-
-    return watcher;
-}
diff --git a/desktop/src/main/services/fs.ts b/desktop/src/main/services/fs.ts
index 7a29d581b..30ccf146b 100644
--- a/desktop/src/main/services/fs.ts
+++ b/desktop/src/main/services/fs.ts
@@ -91,19 +91,6 @@ export async function getElectronFile(filePath: string): Promise<ElectronFile> {
     };
 }
 
-export const getValidPaths = (paths: string[]) => {
-    if (!paths) {
-        return [] as string[];
-    }
-    return paths.filter(async (path) => {
-        try {
-            await fs.stat(path).then((stat) => stat.isFile());
-        } catch (e) {
-            return false;
-        }
-    });
-};
-
 export const getZipFileStream = async (
     zip: StreamZip.StreamZipAsync,
     filePath: string,
diff --git a/desktop/src/main/services/imageProcessor.ts b/desktop/src/main/services/imageProcessor.ts
index e1119d50f..f636c153a 100644
--- a/desktop/src/main/services/imageProcessor.ts
+++ b/desktop/src/main/services/imageProcessor.ts
@@ -3,7 +3,6 @@ import fs from "node:fs/promises";
 import path from "path";
 import { CustomErrors, ElectronFile } from "../../types/ipc";
 import log from "../log";
-import { isPlatform } from "../platform";
 import { writeStream } from "../stream";
 import { generateTempFilePath } from "../temp";
 import { execAsync, isDev } from "../util";
@@ -74,9 +73,8 @@ export async function convertToJPEG(
     fileData: Uint8Array,
     filename: string,
 ): Promise<Uint8Array> {
-    if (isPlatform("windows")) {
+    if (process.platform == "win32")
         throw Error(CustomErrors.WINDOWS_NATIVE_IMAGE_PROCESSING_NOT_SUPPORTED);
-    }
     const convertedFileData = await convertToJPEG_(fileData, filename);
     return convertedFileData;
 }
@@ -123,7 +121,7 @@ function constructConvertCommand(
     tempOutputFilePath: string,
 ) {
     let convertCmd: string[];
-    if (isPlatform("mac")) {
+    if (process.platform == "darwin") {
         convertCmd = SIPS_HEIC_CONVERT_COMMAND_TEMPLATE.map((cmdPart) => {
             if (cmdPart === INPUT_PATH_PLACEHOLDER) {
                 return tempInputFilePath;
@@ -133,7 +131,7 @@ function constructConvertCommand(
             }
             return cmdPart;
         });
-    } else if (isPlatform("linux")) {
+    } else if (process.platform == "linux") {
         convertCmd = IMAGEMAGICK_HEIC_CONVERT_COMMAND_TEMPLATE.map(
             (cmdPart) => {
                 if (cmdPart === IMAGE_MAGICK_PLACEHOLDER) {
@@ -162,11 +160,10 @@ export async function generateImageThumbnail(
     let inputFilePath = null;
     let createdTempInputFile = null;
     try {
-        if (isPlatform("windows")) {
+        if (process.platform == "win32")
             throw Error(
                 CustomErrors.WINDOWS_NATIVE_IMAGE_PROCESSING_NOT_SUPPORTED,
             );
-        }
         if (!existsSync(inputFile.path)) {
             const tempFilePath = await generateTempFilePath(inputFile.name);
             await writeStream(tempFilePath, await inputFile.stream());
@@ -237,7 +234,7 @@ function constructThumbnailGenerationCommand(
     quality: number,
 ) {
     let thumbnailGenerationCmd: string[];
-    if (isPlatform("mac")) {
+    if (process.platform == "darwin") {
         thumbnailGenerationCmd = SIPS_THUMBNAIL_GENERATE_COMMAND_TEMPLATE.map(
             (cmdPart) => {
                 if (cmdPart === INPUT_PATH_PLACEHOLDER) {
@@ -255,7 +252,7 @@ function constructThumbnailGenerationCommand(
                 return cmdPart;
             },
         );
-    } else if (isPlatform("linux")) {
+    } else if (process.platform == "linux") {
         thumbnailGenerationCmd =
             IMAGE_MAGICK_THUMBNAIL_GENERATE_COMMAND_TEMPLATE.map((cmdPart) => {
                 if (cmdPart === IMAGE_MAGICK_PLACEHOLDER) {
diff --git a/desktop/src/main/services/store.ts b/desktop/src/main/services/store.ts
index a484080f5..9ec65c8c3 100644
--- a/desktop/src/main/services/store.ts
+++ b/desktop/src/main/services/store.ts
@@ -1,12 +1,15 @@
 import { safeStorage } from "electron/main";
-import { keysStore } from "../stores/keys.store";
-import { safeStorageStore } from "../stores/safeStorage.store";
-import { uploadStatusStore } from "../stores/upload.store";
-import { watchStore } from "../stores/watch.store";
+import { safeStorageStore } from "../stores/safe-storage";
+import { uploadStatusStore } from "../stores/upload-status";
+import { watchStore } from "../stores/watch";
 
+/**
+ * Clear all stores except user preferences.
+ *
+ * This is useful to reset state when the user logs out.
+ */
 export const clearStores = () => {
     uploadStatusStore.clear();
-    keysStore.clear();
     safeStorageStore.clear();
     watchStore.clear();
 };
diff --git a/desktop/src/main/services/upload.ts b/desktop/src/main/services/upload.ts
index e3fbc16e6..88c2d88d1 100644
--- a/desktop/src/main/services/upload.ts
+++ b/desktop/src/main/services/upload.ts
@@ -1,19 +1,23 @@
 import StreamZip from "node-stream-zip";
+import { existsSync } from "original-fs";
 import path from "path";
-import { ElectronFile, FILE_PATH_TYPE } from "../../types/ipc";
-import { FILE_PATH_KEYS } from "../../types/main";
-import { uploadStatusStore } from "../stores/upload.store";
-import { getElectronFile, getValidPaths, getZipFileStream } from "./fs";
+import { ElectronFile, type PendingUploads } from "../../types/ipc";
+import {
+    uploadStatusStore,
+    type UploadStatusStore,
+} from "../stores/upload-status";
+import { getElectronFile, getZipFileStream } from "./fs";
 
-export const getPendingUploads = async () => {
-    const filePaths = getSavedFilePaths(FILE_PATH_TYPE.FILES);
-    const zipPaths = getSavedFilePaths(FILE_PATH_TYPE.ZIPS);
+export const pendingUploads = async () => {
     const collectionName = uploadStatusStore.get("collectionName");
+    const filePaths = validSavedPaths("files");
+    const zipPaths = validSavedPaths("zips");
 
     let files: ElectronFile[] = [];
-    let type: FILE_PATH_TYPE;
+    let type: PendingUploads["type"];
+
     if (zipPaths.length) {
-        type = FILE_PATH_TYPE.ZIPS;
+        type = "zips";
         for (const zipPath of zipPaths) {
             files = [
                 ...files,
@@ -23,9 +27,10 @@ export const getPendingUploads = async () => {
         const pendingFilePaths = new Set(filePaths);
         files = files.filter((file) => pendingFilePaths.has(file.path));
     } else if (filePaths.length) {
-        type = FILE_PATH_TYPE.FILES;
+        type = "files";
         files = await Promise.all(filePaths.map(getElectronFile));
     }
+
     return {
         files,
         collectionName,
@@ -33,16 +38,56 @@ export const getPendingUploads = async () => {
     };
 };
 
-export const getSavedFilePaths = (type: FILE_PATH_TYPE) => {
-    const paths =
-        getValidPaths(
-            uploadStatusStore.get(FILE_PATH_KEYS[type]) as string[],
-        ) ?? [];
-
-    setToUploadFiles(type, paths);
+export const validSavedPaths = (type: PendingUploads["type"]) => {
+    const key = storeKey(type);
+    const savedPaths = (uploadStatusStore.get(key) as string[]) ?? [];
+    const paths = savedPaths.filter((p) => existsSync(p));
+    uploadStatusStore.set(key, paths);
     return paths;
 };
 
+export const setPendingUploadCollection = (collectionName: string) => {
+    if (collectionName) uploadStatusStore.set("collectionName", collectionName);
+    else uploadStatusStore.delete("collectionName");
+};
+
+export const setPendingUploadFiles = (
+    type: PendingUploads["type"],
+    filePaths: string[],
+) => {
+    const key = storeKey(type);
+    if (filePaths) uploadStatusStore.set(key, filePaths);
+    else uploadStatusStore.delete(key);
+};
+
+const storeKey = (type: PendingUploads["type"]): keyof UploadStatusStore => {
+    switch (type) {
+        case "zips":
+            return "zipPaths";
+        case "files":
+            return "filePaths";
+    }
+};
+
+export const getElectronFilesFromGoogleZip = async (filePath: string) => {
+    const zip = new StreamZip.async({
+        file: filePath,
+    });
+    const zipName = path.basename(filePath, ".zip");
+
+    const entries = await zip.entries();
+    const files: ElectronFile[] = [];
+
+    for (const entry of Object.values(entries)) {
+        const basename = path.basename(entry.name);
+        if (entry.isFile && basename.length > 0 && basename[0] !== ".") {
+            files.push(await getZipEntryAsElectronFile(zipName, zip, entry));
+        }
+    }
+
+    return files;
+};
+
 export async function getZipEntryAsElectronFile(
     zipName: string,
     zip: StreamZip.StreamZipAsync,
@@ -69,39 +114,3 @@ export async function getZipEntryAsElectronFile(
         },
     };
 }
-
-export const setToUploadFiles = (type: FILE_PATH_TYPE, filePaths: string[]) => {
-    const key = FILE_PATH_KEYS[type];
-    if (filePaths) {
-        uploadStatusStore.set(key, filePaths);
-    } else {
-        uploadStatusStore.delete(key);
-    }
-};
-
-export const setToUploadCollection = (collectionName: string) => {
-    if (collectionName) {
-        uploadStatusStore.set("collectionName", collectionName);
-    } else {
-        uploadStatusStore.delete("collectionName");
-    }
-};
-
-export const getElectronFilesFromGoogleZip = async (filePath: string) => {
-    const zip = new StreamZip.async({
-        file: filePath,
-    });
-    const zipName = path.basename(filePath, ".zip");
-
-    const entries = await zip.entries();
-    const files: ElectronFile[] = [];
-
-    for (const entry of Object.values(entries)) {
-        const basename = path.basename(entry.name);
-        if (entry.isFile && basename.length > 0 && basename[0] !== ".") {
-            files.push(await getZipEntryAsElectronFile(zipName, zip, entry));
-        }
-    }
-
-    return files;
-};
diff --git a/desktop/src/main/services/watch.ts b/desktop/src/main/services/watch.ts
index 1d466d415..73a13c545 100644
--- a/desktop/src/main/services/watch.ts
+++ b/desktop/src/main/services/watch.ts
@@ -1,101 +1,159 @@
-import type { FSWatcher } from "chokidar";
-import ElectronLog from "electron-log";
-import { FolderWatch, WatchStoreType } from "../../types/ipc";
-import { watchStore } from "../stores/watch.store";
+import chokidar, { type FSWatcher } from "chokidar";
+import { BrowserWindow } from "electron/main";
+import fs from "node:fs/promises";
+import path from "node:path";
+import { FolderWatch, type CollectionMapping } from "../../types/ipc";
+import { fsIsDir } from "../fs";
+import log from "../log";
+import { watchStore } from "../stores/watch";
 
-export const addWatchMapping = async (
-    watcher: FSWatcher,
-    rootFolderName: string,
-    folderPath: string,
-    uploadStrategy: number,
-) => {
-    ElectronLog.log(`Adding watch mapping: ${folderPath}`);
-    const watchMappings = getWatchMappings();
-    if (isMappingPresent(watchMappings, folderPath)) {
-        throw new Error(`Watch mapping already exists`);
+/**
+ * Create and return a new file system watcher.
+ *
+ * Internally this uses the watcher from the chokidar package.
+ *
+ * @param mainWindow The window handle is used to notify the renderer process of
+ * pertinent file system events.
+ */
+export const createWatcher = (mainWindow: BrowserWindow) => {
+    const send = (eventName: string) => (path: string) =>
+        mainWindow.webContents.send(eventName, ...eventData(path));
+
+    const folderPaths = folderWatches().map((watch) => watch.folderPath);
+
+    const watcher = chokidar.watch(folderPaths, {
+        awaitWriteFinish: true,
+    });
+
+    watcher
+        .on("add", send("watchAddFile"))
+        .on("unlink", send("watchRemoveFile"))
+        .on("unlinkDir", send("watchRemoveDir"))
+        .on("error", (error) => log.error("Error while watching files", error));
+
+    return watcher;
+};
+
+const eventData = (path: string): [string, FolderWatch] => {
+    path = posixPath(path);
+
+    const watch = folderWatches().find((watch) =>
+        path.startsWith(watch.folderPath + "/"),
+    );
+
+    if (!watch) throw new Error(`No folder watch was found for path ${path}`);
+
+    return [path, watch];
+};
+
+/**
+ * Convert a file system {@link filePath} that uses the local system specific
+ * path separators into a path that uses POSIX file separators.
+ */
+const posixPath = (filePath: string) =>
+    filePath.split(path.sep).join(path.posix.sep);
+
+export const watchGet = (watcher: FSWatcher) => {
+    const [valid, deleted] = folderWatches().reduce(
+        ([valid, deleted], watch) => {
+            (fsIsDir(watch.folderPath) ? valid : deleted).push(watch);
+            return [valid, deleted];
+        },
+        [[], []],
+    );
+    if (deleted.length) {
+        for (const watch of deleted) watchRemove(watcher, watch.folderPath);
+        setFolderWatches(valid);
     }
+    return valid;
+};
 
-    watcher.add(folderPath);
+const folderWatches = (): FolderWatch[] => watchStore.get("mappings") ?? [];
 
-    watchMappings.push({
-        rootFolderName,
-        uploadStrategy,
+const setFolderWatches = (watches: FolderWatch[]) =>
+    watchStore.set("mappings", watches);
+
+export const watchAdd = async (
+    watcher: FSWatcher,
+    folderPath: string,
+    collectionMapping: CollectionMapping,
+) => {
+    const watches = folderWatches();
+
+    if (!fsIsDir(folderPath))
+        throw new Error(
+            `Attempting to add a folder watch for a folder path ${folderPath} that is not an existing directory`,
+        );
+
+    if (watches.find((watch) => watch.folderPath == folderPath))
+        throw new Error(
+            `A folder watch with the given folder path ${folderPath} already exists`,
+        );
+
+    watches.push({
         folderPath,
+        collectionMapping,
         syncedFiles: [],
         ignoredFiles: [],
     });
 
-    setWatchMappings(watchMappings);
+    setFolderWatches(watches);
+
+    watcher.add(folderPath);
+
+    return watches;
 };
 
-function isMappingPresent(watchMappings: FolderWatch[], folderPath: string) {
-    const watchMapping = watchMappings?.find(
-        (mapping) => mapping.folderPath === folderPath,
-    );
-    return !!watchMapping;
-}
+export const watchRemove = async (watcher: FSWatcher, folderPath: string) => {
+    const watches = folderWatches();
+    const filtered = watches.filter((watch) => watch.folderPath != folderPath);
+    if (watches.length == filtered.length)
+        throw new Error(
+            `Attempting to remove a non-existing folder watch for folder path ${folderPath}`,
+        );
+    setFolderWatches(filtered);
+    watcher.unwatch(folderPath);
+    return filtered;
+};
 
-export const removeWatchMapping = async (
-    watcher: FSWatcher,
+export const watchUpdateSyncedFiles = (
+    syncedFiles: FolderWatch["syncedFiles"],
     folderPath: string,
 ) => {
-    let watchMappings = getWatchMappings();
-    const watchMapping = watchMappings.find(
-        (mapping) => mapping.folderPath === folderPath,
+    setFolderWatches(
+        folderWatches().map((watch) => {
+            if (watch.folderPath == folderPath) {
+                watch.syncedFiles = syncedFiles;
+            }
+            return watch;
+        }),
     );
-
-    if (!watchMapping) {
-        throw new Error(`Watch mapping does not exist`);
-    }
-
-    watcher.unwatch(watchMapping.folderPath);
-
-    watchMappings = watchMappings.filter(
-        (mapping) => mapping.folderPath !== watchMapping.folderPath,
-    );
-
-    setWatchMappings(watchMappings);
 };
 
-export function updateWatchMappingSyncedFiles(
+export const watchUpdateIgnoredFiles = (
+    ignoredFiles: FolderWatch["ignoredFiles"],
     folderPath: string,
-    files: FolderWatch["syncedFiles"],
-): void {
-    const watchMappings = getWatchMappings();
-    const watchMapping = watchMappings.find(
-        (mapping) => mapping.folderPath === folderPath,
+) => {
+    setFolderWatches(
+        folderWatches().map((watch) => {
+            if (watch.folderPath == folderPath) {
+                watch.ignoredFiles = ignoredFiles;
+            }
+            return watch;
+        }),
     );
+};
 
-    if (!watchMapping) {
-        throw Error(`Watch mapping not found`);
+export const watchFindFiles = async (dirPath: string) => {
+    const items = await fs.readdir(dirPath, { withFileTypes: true });
+    let paths: string[] = [];
+    for (const item of items) {
+        const itemPath = path.posix.join(dirPath, item.name);
+        if (item.isFile()) {
+            paths.push(itemPath);
+        } else if (item.isDirectory()) {
+            paths = [...paths, ...(await watchFindFiles(itemPath))];
+        }
     }
-
-    watchMapping.syncedFiles = files;
-    setWatchMappings(watchMappings);
-}
-
-export function updateWatchMappingIgnoredFiles(
-    folderPath: string,
-    files: FolderWatch["ignoredFiles"],
-): void {
-    const watchMappings = getWatchMappings();
-    const watchMapping = watchMappings.find(
-        (mapping) => mapping.folderPath === folderPath,
-    );
-
-    if (!watchMapping) {
-        throw Error(`Watch mapping not found`);
-    }
-
-    watchMapping.ignoredFiles = files;
-    setWatchMappings(watchMappings);
-}
-
-export function getWatchMappings() {
-    const mappings = watchStore.get("mappings") ?? [];
-    return mappings;
-}
-
-function setWatchMappings(watchMappings: WatchStoreType["mappings"]) {
-    watchStore.set("mappings", watchMappings);
-}
+    return paths;
+};
diff --git a/desktop/src/main/stores/keys.store.ts b/desktop/src/main/stores/keys.store.ts
deleted file mode 100644
index 4f8618cea..000000000
--- a/desktop/src/main/stores/keys.store.ts
+++ /dev/null
@@ -1,18 +0,0 @@
-import Store, { Schema } from "electron-store";
-import type { KeysStoreType } from "../../types/main";
-
-const keysStoreSchema: Schema<KeysStoreType> = {
-    AnonymizeUserID: {
-        type: "object",
-        properties: {
-            id: {
-                type: "string",
-            },
-        },
-    },
-};
-
-export const keysStore = new Store({
-    name: "keys",
-    schema: keysStoreSchema,
-});
diff --git a/desktop/src/main/stores/safeStorage.store.ts b/desktop/src/main/stores/safe-storage.ts
similarity index 63%
rename from desktop/src/main/stores/safeStorage.store.ts
rename to desktop/src/main/stores/safe-storage.ts
index da95df3be..1e1369db8 100644
--- a/desktop/src/main/stores/safeStorage.store.ts
+++ b/desktop/src/main/stores/safe-storage.ts
@@ -1,7 +1,10 @@
 import Store, { Schema } from "electron-store";
-import type { SafeStorageStoreType } from "../../types/main";
 
-const safeStorageSchema: Schema<SafeStorageStoreType> = {
+interface SafeStorageStore {
+    encryptionKey: string;
+}
+
+const safeStorageSchema: Schema<SafeStorageStore> = {
     encryptionKey: {
         type: "string",
     },
diff --git a/desktop/src/main/stores/upload.store.ts b/desktop/src/main/stores/upload-status.ts
similarity index 65%
rename from desktop/src/main/stores/upload.store.ts
rename to desktop/src/main/stores/upload-status.ts
index 20b1f419d..25af7a49e 100644
--- a/desktop/src/main/stores/upload.store.ts
+++ b/desktop/src/main/stores/upload-status.ts
@@ -1,7 +1,12 @@
 import Store, { Schema } from "electron-store";
-import type { UploadStoreType } from "../../types/main";
 
-const uploadStoreSchema: Schema<UploadStoreType> = {
+export interface UploadStatusStore {
+    filePaths: string[];
+    zipPaths: string[];
+    collectionName: string;
+}
+
+const uploadStatusSchema: Schema<UploadStatusStore> = {
     filePaths: {
         type: "array",
         items: {
@@ -21,5 +26,5 @@ const uploadStoreSchema: Schema<UploadStoreType> = {
 
 export const uploadStatusStore = new Store({
     name: "upload-status",
-    schema: uploadStoreSchema,
+    schema: uploadStatusSchema,
 });
diff --git a/desktop/src/main/stores/user-preferences.ts b/desktop/src/main/stores/user-preferences.ts
index a305f1a99..b4a02bc5b 100644
--- a/desktop/src/main/stores/user-preferences.ts
+++ b/desktop/src/main/stores/user-preferences.ts
@@ -1,12 +1,12 @@
 import Store, { Schema } from "electron-store";
 
-interface UserPreferencesSchema {
+interface UserPreferences {
     hideDockIcon: boolean;
     skipAppVersion?: string;
     muteUpdateNotificationVersion?: string;
 }
 
-const userPreferencesSchema: Schema<UserPreferencesSchema> = {
+const userPreferencesSchema: Schema<UserPreferences> = {
     hideDockIcon: {
         type: "boolean",
     },
diff --git a/desktop/src/main/stores/watch.store.ts b/desktop/src/main/stores/watch.store.ts
deleted file mode 100644
index 55470ce86..000000000
--- a/desktop/src/main/stores/watch.store.ts
+++ /dev/null
@@ -1,47 +0,0 @@
-import Store, { Schema } from "electron-store";
-import { WatchStoreType } from "../../types/ipc";
-
-const watchStoreSchema: Schema<WatchStoreType> = {
-    mappings: {
-        type: "array",
-        items: {
-            type: "object",
-            properties: {
-                rootFolderName: {
-                    type: "string",
-                },
-                uploadStrategy: {
-                    type: "number",
-                },
-                folderPath: {
-                    type: "string",
-                },
-                syncedFiles: {
-                    type: "array",
-                    items: {
-                        type: "object",
-                        properties: {
-                            path: {
-                                type: "string",
-                            },
-                            id: {
-                                type: "number",
-                            },
-                        },
-                    },
-                },
-                ignoredFiles: {
-                    type: "array",
-                    items: {
-                        type: "string",
-                    },
-                },
-            },
-        },
-    },
-};
-
-export const watchStore = new Store({
-    name: "watch-status",
-    schema: watchStoreSchema,
-});
diff --git a/desktop/src/main/stores/watch.ts b/desktop/src/main/stores/watch.ts
new file mode 100644
index 000000000..7ee383038
--- /dev/null
+++ b/desktop/src/main/stores/watch.ts
@@ -0,0 +1,73 @@
+import Store, { Schema } from "electron-store";
+import { type FolderWatch } from "../../types/ipc";
+import log from "../log";
+
+interface WatchStore {
+    mappings: FolderWatchWithLegacyFields[];
+}
+
+type FolderWatchWithLegacyFields = FolderWatch & {
+    /** @deprecated Only retained for migration, do not use in other code */
+    rootFolderName?: string;
+    /** @deprecated Only retained for migration, do not use in other code */
+    uploadStrategy?: number;
+};
+
+const watchStoreSchema: Schema<WatchStore> = {
+    mappings: {
+        type: "array",
+        items: {
+            type: "object",
+            properties: {
+                rootFolderName: { type: "string" },
+                collectionMapping: { type: "string" },
+                uploadStrategy: { type: "number" },
+                folderPath: { type: "string" },
+                syncedFiles: {
+                    type: "array",
+                    items: {
+                        type: "object",
+                        properties: {
+                            path: { type: "string" },
+                            uploadedFileID: { type: "number" },
+                            collectionID: { type: "number" },
+                        },
+                    },
+                },
+                ignoredFiles: {
+                    type: "array",
+                    items: { type: "string" },
+                },
+            },
+        },
+    },
+};
+
+export const watchStore = new Store({
+    name: "watch-status",
+    schema: watchStoreSchema,
+});
+
+/**
+ * Previous versions of the store used to store an integer to indicate the
+ * collection mapping, migrate these to the new schema if we encounter them.
+ */
+export const migrateLegacyWatchStoreIfNeeded = () => {
+    let needsUpdate = false;
+    const watches = watchStore.get("mappings")?.map((watch) => {
+        let collectionMapping = watch.collectionMapping;
+        if (!collectionMapping) {
+            collectionMapping = watch.uploadStrategy == 1 ? "parent" : "root";
+            needsUpdate = true;
+        }
+        if (watch.rootFolderName) {
+            delete watch.rootFolderName;
+            needsUpdate = true;
+        }
+        return { ...watch, collectionMapping };
+    });
+    if (needsUpdate) {
+        watchStore.set("mappings", watches);
+        log.info("Migrated legacy watch store data to new schema");
+    }
+};
diff --git a/desktop/src/main/util.ts b/desktop/src/main/util.ts
index d0c6699e9..b997d738e 100644
--- a/desktop/src/main/util.ts
+++ b/desktop/src/main/util.ts
@@ -56,6 +56,13 @@ export const openDirectory = async (dirPath: string) => {
     if (res) throw new Error(`Failed to open directory ${dirPath}: res`);
 };
 
+/**
+ * Open the app's log directory in the system's folder viewer.
+ *
+ * @see {@link openDirectory}
+ */
+export const openLogDirectory = () => openDirectory(logDirectoryPath());
+
 /**
  * Return the path where the logs for the app are saved.
  *
@@ -72,10 +79,3 @@ export const openDirectory = async (dirPath: string) => {
  *
  */
 const logDirectoryPath = () => app.getPath("logs");
-
-/**
- * Open the app's log directory in the system's folder viewer.
- *
- * @see {@link openDirectory}
- */
-export const openLogDirectory = () => openDirectory(logDirectoryPath());
diff --git a/desktop/src/preload.ts b/desktop/src/preload.ts
index 2749fa50d..7d0df41d5 100644
--- a/desktop/src/preload.ts
+++ b/desktop/src/preload.ts
@@ -40,12 +40,13 @@
 import { contextBridge, ipcRenderer } from "electron/renderer";
 
 // While we can't import other code, we can import types since they're just
-// needed when compiling and will not be needed / looked around for at runtime.
+// needed when compiling and will not be needed or looked around for at runtime.
 import type {
-    AppUpdateInfo,
+    AppUpdate,
+    CollectionMapping,
     ElectronFile,
-    FILE_PATH_TYPE,
     FolderWatch,
+    PendingUploads,
 } from "./types/ipc";
 
 // - General
@@ -77,12 +78,12 @@ const onMainWindowFocus = (cb?: () => void) => {
 // - App update
 
 const onAppUpdateAvailable = (
-    cb?: ((updateInfo: AppUpdateInfo) => void) | undefined,
+    cb?: ((update: AppUpdate) => void) | undefined,
 ) => {
     ipcRenderer.removeAllListeners("appUpdateAvailable");
     if (cb) {
-        ipcRenderer.on("appUpdateAvailable", (_, updateInfo: AppUpdateInfo) =>
-            cb(updateInfo),
+        ipcRenderer.on("appUpdateAvailable", (_, update: AppUpdate) =>
+            cb(update),
         );
     }
 };
@@ -118,6 +119,9 @@ const fsReadTextFile = (path: string): Promise<string> =>
 const fsWriteFile = (path: string, contents: string): Promise<void> =>
     ipcRenderer.invoke("fsWriteFile", path, contents);
 
+const fsIsDir = (dirPath: string): Promise<boolean> =>
+    ipcRenderer.invoke("fsIsDir", dirPath);
+
 // - AUDIT below this
 
 // - Conversion
@@ -188,82 +192,78 @@ const showUploadZipDialog = (): Promise<{
 
 // - Watch
 
-const registerWatcherFunctions = (
-    addFile: (file: ElectronFile) => Promise<void>,
-    removeFile: (path: string) => Promise<void>,
-    removeFolder: (folderPath: string) => Promise<void>,
-) => {
-    ipcRenderer.removeAllListeners("watch-add");
-    ipcRenderer.removeAllListeners("watch-unlink");
-    ipcRenderer.removeAllListeners("watch-unlink-dir");
-    ipcRenderer.on("watch-add", (_, file: ElectronFile) => addFile(file));
-    ipcRenderer.on("watch-unlink", (_, filePath: string) =>
-        removeFile(filePath),
-    );
-    ipcRenderer.on("watch-unlink-dir", (_, folderPath: string) =>
-        removeFolder(folderPath),
+const watchGet = (): Promise<FolderWatch[]> => ipcRenderer.invoke("watchGet");
+
+const watchAdd = (
+    folderPath: string,
+    collectionMapping: CollectionMapping,
+): Promise<FolderWatch[]> =>
+    ipcRenderer.invoke("watchAdd", folderPath, collectionMapping);
+
+const watchRemove = (folderPath: string): Promise<FolderWatch[]> =>
+    ipcRenderer.invoke("watchRemove", folderPath);
+
+const watchUpdateSyncedFiles = (
+    syncedFiles: FolderWatch["syncedFiles"],
+    folderPath: string,
+): Promise<void> =>
+    ipcRenderer.invoke("watchUpdateSyncedFiles", syncedFiles, folderPath);
+
+const watchUpdateIgnoredFiles = (
+    ignoredFiles: FolderWatch["ignoredFiles"],
+    folderPath: string,
+): Promise<void> =>
+    ipcRenderer.invoke("watchUpdateIgnoredFiles", ignoredFiles, folderPath);
+
+const watchOnAddFile = (f: (path: string, watch: FolderWatch) => void) => {
+    ipcRenderer.removeAllListeners("watchAddFile");
+    ipcRenderer.on("watchAddFile", (_, path: string, watch: FolderWatch) =>
+        f(path, watch),
     );
 };
 
-const addWatchMapping = (
-    collectionName: string,
-    folderPath: string,
-    uploadStrategy: number,
-): Promise<void> =>
-    ipcRenderer.invoke(
-        "addWatchMapping",
-        collectionName,
-        folderPath,
-        uploadStrategy,
+const watchOnRemoveFile = (f: (path: string, watch: FolderWatch) => void) => {
+    ipcRenderer.removeAllListeners("watchRemoveFile");
+    ipcRenderer.on("watchRemoveFile", (_, path: string, watch: FolderWatch) =>
+        f(path, watch),
     );
+};
 
-const removeWatchMapping = (folderPath: string): Promise<void> =>
-    ipcRenderer.invoke("removeWatchMapping", folderPath);
+const watchOnRemoveDir = (f: (path: string, watch: FolderWatch) => void) => {
+    ipcRenderer.removeAllListeners("watchRemoveDir");
+    ipcRenderer.on("watchRemoveDir", (_, path: string, watch: FolderWatch) =>
+        f(path, watch),
+    );
+};
 
-const getWatchMappings = (): Promise<FolderWatch[]> =>
-    ipcRenderer.invoke("getWatchMappings");
-
-const updateWatchMappingSyncedFiles = (
-    folderPath: string,
-    files: FolderWatch["syncedFiles"],
-): Promise<void> =>
-    ipcRenderer.invoke("updateWatchMappingSyncedFiles", folderPath, files);
-
-const updateWatchMappingIgnoredFiles = (
-    folderPath: string,
-    files: FolderWatch["ignoredFiles"],
-): Promise<void> =>
-    ipcRenderer.invoke("updateWatchMappingIgnoredFiles", folderPath, files);
-
-// - FS Legacy
-
-const isFolder = (dirPath: string): Promise<boolean> =>
-    ipcRenderer.invoke("isFolder", dirPath);
+const watchFindFiles = (folderPath: string): Promise<string[]> =>
+    ipcRenderer.invoke("watchFindFiles", folderPath);
 
 // - Upload
 
-const getPendingUploads = (): Promise<{
-    files: ElectronFile[];
-    collectionName: string;
-    type: string;
-}> => ipcRenderer.invoke("getPendingUploads");
+const pendingUploads = (): Promise<PendingUploads | undefined> =>
+    ipcRenderer.invoke("pendingUploads");
 
-const setToUploadFiles = (
-    type: FILE_PATH_TYPE,
+const setPendingUploadCollection = (collectionName: string): Promise<void> =>
+    ipcRenderer.invoke("setPendingUploadCollection", collectionName);
+
+const setPendingUploadFiles = (
+    type: PendingUploads["type"],
     filePaths: string[],
-): Promise<void> => ipcRenderer.invoke("setToUploadFiles", type, filePaths);
+): Promise<void> =>
+    ipcRenderer.invoke("setPendingUploadFiles", type, filePaths);
+
+// -
 
 const getElectronFilesFromGoogleZip = (
     filePath: string,
 ): Promise<ElectronFile[]> =>
     ipcRenderer.invoke("getElectronFilesFromGoogleZip", filePath);
 
-const setToUploadCollection = (collectionName: string): Promise<void> =>
-    ipcRenderer.invoke("setToUploadCollection", collectionName);
-
 const getDirFiles = (dirPath: string): Promise<ElectronFile[]> =>
     ipcRenderer.invoke("getDirFiles", dirPath);
 
+//
 // These objects exposed here will become available to the JS code in our
 // renderer (the web/ code) as `window.ElectronAPIs.*`
 //
@@ -295,10 +295,13 @@ const getDirFiles = (dirPath: string): Promise<ElectronFile[]> =>
 //   https://www.electronjs.org/docs/latest/api/context-bridge#methods
 //
 // The copy itself is relatively fast, but the problem with transfering large
-// amounts of data is potentially running out of memory during the copy. For an
-// alternative, see [Note: IPC streams].
+// amounts of data is potentially running out of memory during the copy.
+//
+// For an alternative, see [Note: IPC streams].
+//
 contextBridge.exposeInMainWorld("electron", {
     // - General
+
     appVersion,
     logToDisk,
     openDirectory,
@@ -309,12 +312,14 @@ contextBridge.exposeInMainWorld("electron", {
     onMainWindowFocus,
 
     // - App update
+
     onAppUpdateAvailable,
     updateAndRestart,
     updateOnNextRestart,
     skipAppUpdate,
 
     // - FS
+
     fs: {
         exists: fsExists,
         rename: fsRename,
@@ -323,42 +328,51 @@ contextBridge.exposeInMainWorld("electron", {
         rm: fsRm,
         readTextFile: fsReadTextFile,
         writeFile: fsWriteFile,
+        isDir: fsIsDir,
     },
 
     // - Conversion
+
     convertToJPEG,
     generateImageThumbnail,
     runFFmpegCmd,
 
     // - ML
+
     clipImageEmbedding,
     clipTextEmbedding,
     detectFaces,
     faceEmbedding,
 
     // - File selection
+
     selectDirectory,
     showUploadFilesDialog,
     showUploadDirsDialog,
     showUploadZipDialog,
 
     // - Watch
-    registerWatcherFunctions,
-    addWatchMapping,
-    removeWatchMapping,
-    getWatchMappings,
-    updateWatchMappingSyncedFiles,
-    updateWatchMappingIgnoredFiles,
 
-    // - FS legacy
-    // TODO: Move these into fs + document + rename if needed
-    isFolder,
+    watch: {
+        get: watchGet,
+        add: watchAdd,
+        remove: watchRemove,
+        onAddFile: watchOnAddFile,
+        onRemoveFile: watchOnRemoveFile,
+        onRemoveDir: watchOnRemoveDir,
+        findFiles: watchFindFiles,
+        updateSyncedFiles: watchUpdateSyncedFiles,
+        updateIgnoredFiles: watchUpdateIgnoredFiles,
+    },
 
     // - Upload
 
-    getPendingUploads,
-    setToUploadFiles,
+    pendingUploads,
+    setPendingUploadCollection,
+    setPendingUploadFiles,
+
+    // -
+
     getElectronFilesFromGoogleZip,
-    setToUploadCollection,
     getDirFiles,
 });
diff --git a/desktop/src/types/ipc.ts b/desktop/src/types/ipc.ts
index 3dae605a8..d96341982 100644
--- a/desktop/src/types/ipc.ts
+++ b/desktop/src/types/ipc.ts
@@ -5,20 +5,32 @@
  * See [Note: types.ts <-> preload.ts <-> ipc.ts]
  */
 
+export interface AppUpdate {
+    autoUpdatable: boolean;
+    version: string;
+}
+
 export interface FolderWatch {
-    rootFolderName: string;
-    uploadStrategy: number;
+    collectionMapping: CollectionMapping;
     folderPath: string;
     syncedFiles: FolderWatchSyncedFile[];
     ignoredFiles: string[];
 }
 
+export type CollectionMapping = "root" | "parent";
+
 export interface FolderWatchSyncedFile {
     path: string;
     uploadedFileID: number;
     collectionID: number;
 }
 
+export interface PendingUploads {
+    collectionName: string;
+    type: "files" | "zips";
+    files: ElectronFile[];
+}
+
 /**
  * Errors that have special semantics on the web side.
  *
@@ -65,18 +77,3 @@ export interface ElectronFile {
     blob: () => Promise<Blob>;
     arrayBuffer: () => Promise<Uint8Array>;
 }
-
-export interface WatchStoreType {
-    mappings: FolderWatch[];
-}
-
-export enum FILE_PATH_TYPE {
-    /* eslint-disable no-unused-vars */
-    FILES = "files",
-    ZIPS = "zips",
-}
-
-export interface AppUpdateInfo {
-    autoUpdatable: boolean;
-    version: string;
-}
diff --git a/desktop/src/types/main.ts b/desktop/src/types/main.ts
deleted file mode 100644
index 546749c54..000000000
--- a/desktop/src/types/main.ts
+++ /dev/null
@@ -1,31 +0,0 @@
-import { FILE_PATH_TYPE } from "./ipc";
-
-export interface AutoLauncherClient {
-    isEnabled: () => Promise<boolean>;
-    toggleAutoLaunch: () => Promise<void>;
-    wasAutoLaunched: () => Promise<boolean>;
-}
-
-export interface UploadStoreType {
-    filePaths: string[];
-    zipPaths: string[];
-    collectionName: string;
-}
-
-export interface KeysStoreType {
-    AnonymizeUserID: {
-        id: string;
-    };
-}
-
-/* eslint-disable no-unused-vars */
-export const FILE_PATH_KEYS: {
-    [k in FILE_PATH_TYPE]: keyof UploadStoreType;
-} = {
-    [FILE_PATH_TYPE.ZIPS]: "zipPaths",
-    [FILE_PATH_TYPE.FILES]: "filePaths",
-};
-
-export interface SafeStorageStoreType {
-    encryptionKey: string;
-}
diff --git a/web/apps/cast/src/types/upload/index.ts b/web/apps/cast/src/types/upload/index.ts
index ef44b4a23..0e249846a 100644
--- a/web/apps/cast/src/types/upload/index.ts
+++ b/web/apps/cast/src/types/upload/index.ts
@@ -95,13 +95,6 @@ export interface ParsedExtractedMetadata {
     height: number;
 }
 
-// This is used to prompt the user the make upload strategy choice
-export interface ImportSuggestion {
-    rootFolderName: string;
-    hasNestedFolders: boolean;
-    hasRootLevelFileWithFolder: boolean;
-}
-
 export interface PublicUploadProps {
     token: string;
     passwordToken: string;
diff --git a/web/apps/photos/src/components/Sidebar/UtilitySection.tsx b/web/apps/photos/src/components/Sidebar/UtilitySection.tsx
index c9c734cd9..6b4a6f43d 100644
--- a/web/apps/photos/src/components/Sidebar/UtilitySection.tsx
+++ b/web/apps/photos/src/components/Sidebar/UtilitySection.tsx
@@ -206,7 +206,12 @@ export default function UtilitySection({ closeSidebar }) {
                 closeSidebar={closeSidebar}
                 setLoading={startLoading}
             />
-            <WatchFolder open={watchFolderView} onClose={closeWatchFolder} />
+            {isElectron() && (
+                <WatchFolder
+                    open={watchFolderView}
+                    onClose={closeWatchFolder}
+                />
+            )}
             <Preferences
                 open={preferencesView}
                 onClose={closePreferencesOptions}
diff --git a/web/apps/photos/src/components/Upload/UploadStrategyChoiceModal.tsx b/web/apps/photos/src/components/Upload/CollectionMappingChoiceModal.tsx
similarity index 71%
rename from web/apps/photos/src/components/Upload/UploadStrategyChoiceModal.tsx
rename to web/apps/photos/src/components/Upload/CollectionMappingChoiceModal.tsx
index 4e773a3a8..c358a2d1d 100644
--- a/web/apps/photos/src/components/Upload/UploadStrategyChoiceModal.tsx
+++ b/web/apps/photos/src/components/Upload/CollectionMappingChoiceModal.tsx
@@ -1,3 +1,4 @@
+import type { CollectionMapping } from "@/next/types/ipc";
 import {
     CenteredFlex,
     SpaceBetweenFlex,
@@ -8,23 +9,19 @@ import DialogTitleWithCloseButton, {
 import { Button, Dialog, DialogContent, Typography } from "@mui/material";
 import { t } from "i18next";
 
-interface Props {
-    uploadToMultipleCollection: () => void;
+interface CollectionMappingChoiceModalProps {
     open: boolean;
     onClose: () => void;
-    uploadToSingleCollection: () => void;
+    didSelect: (mapping: CollectionMapping) => void;
 }
-function UploadStrategyChoiceModal({
-    uploadToMultipleCollection,
-    uploadToSingleCollection,
-    ...props
-}: Props) {
-    const handleClose = dialogCloseHandler({
-        onClose: props.onClose,
-    });
+
+export const CollectionMappingChoiceModal: React.FC<
+    CollectionMappingChoiceModalProps
+> = ({ open, onClose, didSelect }) => {
+    const handleClose = dialogCloseHandler({ onClose });
 
     return (
-        <Dialog open={props.open} onClose={handleClose}>
+        <Dialog open={open} onClose={handleClose}>
             <DialogTitleWithCloseButton onClose={handleClose}>
                 {t("MULTI_FOLDER_UPLOAD")}
             </DialogTitleWithCloseButton>
@@ -39,8 +36,8 @@ function UploadStrategyChoiceModal({
                         size="medium"
                         color="accent"
                         onClick={() => {
-                            props.onClose();
-                            uploadToSingleCollection();
+                            onClose();
+                            didSelect("root");
                         }}
                     >
                         {t("UPLOAD_STRATEGY_SINGLE_COLLECTION")}
@@ -52,8 +49,8 @@ function UploadStrategyChoiceModal({
                         size="medium"
                         color="accent"
                         onClick={() => {
-                            props.onClose();
-                            uploadToMultipleCollection();
+                            onClose();
+                            didSelect("parent");
                         }}
                     >
                         {t("UPLOAD_STRATEGY_COLLECTION_PER_FOLDER")}
@@ -62,5 +59,4 @@ function UploadStrategyChoiceModal({
             </DialogContent>
         </Dialog>
     );
-}
-export default UploadStrategyChoiceModal;
+};
diff --git a/web/apps/photos/src/components/Upload/Uploader.tsx b/web/apps/photos/src/components/Upload/Uploader.tsx
index bb3d4fd9d..a622953b3 100644
--- a/web/apps/photos/src/components/Upload/Uploader.tsx
+++ b/web/apps/photos/src/components/Upload/Uploader.tsx
@@ -1,15 +1,11 @@
+import { ensureElectron } from "@/next/electron";
 import log from "@/next/log";
-import type { Electron } from "@/next/types/ipc";
+import type { CollectionMapping, Electron } from "@/next/types/ipc";
 import { CustomError } from "@ente/shared/error";
 import { isPromise } from "@ente/shared/utils";
 import DiscFullIcon from "@mui/icons-material/DiscFull";
 import UserNameInputDialog from "components/UserNameInputDialog";
-import {
-    DEFAULT_IMPORT_SUGGESTION,
-    PICKED_UPLOAD_TYPE,
-    UPLOAD_STAGES,
-    UPLOAD_STRATEGY,
-} from "constants/upload";
+import { PICKED_UPLOAD_TYPE, UPLOAD_STAGES } from "constants/upload";
 import { t } from "i18next";
 import isElectron from "is-electron";
 import { AppContext } from "pages/_app";
@@ -17,14 +13,14 @@ import { GalleryContext } from "pages/gallery";
 import { useContext, useEffect, useRef, useState } from "react";
 import billingService from "services/billingService";
 import { getLatestCollections } from "services/collectionService";
-import ImportService from "services/importService";
+import { setToUploadCollection } from "services/pending-uploads";
 import {
     getPublicCollectionUID,
     getPublicCollectionUploaderName,
     savePublicCollectionUploaderName,
 } from "services/publicCollectionService";
 import uploadManager from "services/upload/uploadManager";
-import watchFolderService from "services/watch";
+import watcher from "services/watch";
 import { NotificationAttributes } from "types/Notification";
 import { Collection } from "types/collection";
 import {
@@ -35,11 +31,7 @@ import {
     SetLoading,
     UploadTypeSelectorIntent,
 } from "types/gallery";
-import {
-    ElectronFile,
-    FileWithCollection,
-    ImportSuggestion,
-} from "types/upload";
+import { ElectronFile, FileWithCollection } from "types/upload";
 import {
     InProgressUpload,
     SegregatedFinishedUploads,
@@ -53,13 +45,15 @@ import {
     getRootLevelFileWithFolderNotAllowMessage,
 } from "utils/ui";
 import {
+    DEFAULT_IMPORT_SUGGESTION,
     filterOutSystemFiles,
     getImportSuggestion,
     groupFilesBasedOnParentFolder,
+    type ImportSuggestion,
 } from "utils/upload";
 import { SetCollectionNamerAttributes } from "../Collections/CollectionNamer";
+import { CollectionMappingChoiceModal } from "./CollectionMappingChoiceModal";
 import UploadProgress from "./UploadProgress";
-import UploadStrategyChoiceModal from "./UploadStrategyChoiceModal";
 import UploadTypeSelector from "./UploadTypeSelector";
 
 const FIRST_ALBUM_NAME = "My First Album";
@@ -137,6 +131,7 @@ export default function Uploader(props: Props) {
     const closeUploadProgress = () => setUploadProgressView(false);
     const showUserNameInputDialog = () => setUserNameInputDialogView(true);
 
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
     const setCollectionName = (collectionName: string) => {
         isPendingDesktopUpload.current = true;
         pendingDesktopUploadCollectionName.current = collectionName;
@@ -177,18 +172,27 @@ export default function Uploader(props: Props) {
         }
 
         if (isElectron()) {
-            ImportService.getPendingUploads().then(
-                ({ files: electronFiles, collectionName, type }) => {
-                    log.info(`found pending desktop upload, resuming uploads`);
-                    resumeDesktopUpload(type, electronFiles, collectionName);
-                },
-            );
-            watchFolderService.init(
+            ensureElectron()
+                .pendingUploads()
+                .then((pending) => {
+                    if (pending) {
+                        log.info("Resuming pending desktop upload", pending);
+                        resumeDesktopUpload(
+                            pending.type == "files"
+                                ? PICKED_UPLOAD_TYPE.FILES
+                                : PICKED_UPLOAD_TYPE.ZIPS,
+                            pending.files,
+                            pending.collectionName,
+                        );
+                    }
+                });
+            /* TODO(MR): This is the connection point, implement
+            watcher.init(
                 setElectronFiles,
                 setCollectionName,
                 props.syncWithRemote,
-                appContext.setIsFolderSyncRunning,
             );
+            */
         }
     }, [
         publicCollectionGalleryContext.accessedThroughSharedURL,
@@ -291,18 +295,16 @@ export default function Uploader(props: Props) {
                 }`,
             );
             if (uploadManager.isUploadRunning()) {
-                if (watchFolderService.isUploadRunning()) {
+                if (watcher.isUploadRunning()) {
+                    // Pause watch folder sync on user upload
                     log.info(
-                        "watchFolder upload was running, pausing it to run user upload",
+                        "Folder watcher was uploading, pausing it to first run user upload",
                     );
-                    // pause watch folder service on user upload
-                    watchFolderService.pauseRunningSync();
+                    watcher.pauseRunningSync();
                 } else {
                     log.info(
-                        "an upload is already running, rejecting new upload request",
+                        "Ignoring new upload request because an upload is already running",
                     );
-                    // no-op
-                    // a user upload is already in progress
                     return;
                 }
             }
@@ -330,7 +332,7 @@ export default function Uploader(props: Props) {
 
             const importSuggestion = getImportSuggestion(
                 pickedUploadType.current,
-                toUploadFiles.current,
+                toUploadFiles.current.map((file) => file["path"]),
             );
             setImportSuggestion(importSuggestion);
 
@@ -391,7 +393,7 @@ export default function Uploader(props: Props) {
     };
 
     const uploadFilesToNewCollections = async (
-        strategy: UPLOAD_STRATEGY,
+        strategy: CollectionMapping,
         collectionName?: string,
     ) => {
         try {
@@ -405,7 +407,7 @@ export default function Uploader(props: Props) {
                 string,
                 (File | ElectronFile)[]
             >();
-            if (strategy === UPLOAD_STRATEGY.SINGLE_COLLECTION) {
+            if (strategy == "root") {
                 collectionNameToFilesMap.set(
                     collectionName,
                     toUploadFiles.current,
@@ -505,18 +507,19 @@ export default function Uploader(props: Props) {
             if (
                 electron &&
                 !isPendingDesktopUpload.current &&
-                !watchFolderService.isUploadRunning()
+                !watcher.isUploadRunning()
             ) {
-                await ImportService.setToUploadCollection(collections);
+                await setToUploadCollection(collections);
+                // TODO (MR): What happens when we have both?
                 if (zipPaths.current) {
-                    await electron.setToUploadFiles(
-                        PICKED_UPLOAD_TYPE.ZIPS,
+                    await electron.setPendingUploadFiles(
+                        "zips",
                         zipPaths.current,
                     );
                     zipPaths.current = null;
                 }
-                await electron.setToUploadFiles(
-                    PICKED_UPLOAD_TYPE.FILES,
+                await electron.setPendingUploadFiles(
+                    "files",
                     filesWithCollectionToUploadIn.map(
                         ({ file }) => (file as ElectronFile).path,
                     ),
@@ -532,14 +535,14 @@ export default function Uploader(props: Props) {
                 closeUploadProgress();
             }
             if (isElectron()) {
-                if (watchFolderService.isUploadRunning()) {
-                    await watchFolderService.allFileUploadsDone(
+                if (watcher.isUploadRunning()) {
+                    await watcher.allFileUploadsDone(
                         filesWithCollectionToUploadIn,
                         collections,
                     );
-                } else if (watchFolderService.isSyncPaused()) {
+                } else if (watcher.isSyncPaused()) {
                     // resume the service after user upload is done
-                    watchFolderService.resumePausedSync();
+                    watcher.resumePausedSync();
                 }
             }
         } catch (e) {
@@ -605,10 +608,7 @@ export default function Uploader(props: Props) {
     }
 
     const uploadToSingleNewCollection = (collectionName: string) => {
-        uploadFilesToNewCollections(
-            UPLOAD_STRATEGY.SINGLE_COLLECTION,
-            collectionName,
-        );
+        uploadFilesToNewCollections("root", collectionName);
     };
 
     const showCollectionCreateModal = (suggestedName: string) => {
@@ -647,7 +647,7 @@ export default function Uploader(props: Props) {
                         `upload pending files to collection - ${pendingDesktopUploadCollectionName.current}`,
                     );
                     uploadFilesToNewCollections(
-                        UPLOAD_STRATEGY.SINGLE_COLLECTION,
+                        "root",
                         pendingDesktopUploadCollectionName.current,
                     );
                     pendingDesktopUploadCollectionName.current = null;
@@ -655,17 +655,13 @@ export default function Uploader(props: Props) {
                     log.info(
                         `pending upload - strategy - "multiple collections" `,
                     );
-                    uploadFilesToNewCollections(
-                        UPLOAD_STRATEGY.COLLECTION_PER_FOLDER,
-                    );
+                    uploadFilesToNewCollections("parent");
                 }
                 return;
             }
             if (isElectron() && pickedUploadType === PICKED_UPLOAD_TYPE.ZIPS) {
                 log.info("uploading zip files");
-                uploadFilesToNewCollections(
-                    UPLOAD_STRATEGY.COLLECTION_PER_FOLDER,
-                );
+                uploadFilesToNewCollections("parent");
                 return;
             }
             if (isFirstUpload && !importSuggestion.rootFolderName) {
@@ -784,16 +780,26 @@ export default function Uploader(props: Props) {
             );
             return;
         }
-        uploadFilesToNewCollections(UPLOAD_STRATEGY.COLLECTION_PER_FOLDER);
+        uploadFilesToNewCollections("parent");
+    };
+
+    const didSelectCollectionMapping = (mapping: CollectionMapping) => {
+        switch (mapping) {
+            case "root":
+                handleUploadToSingleCollection();
+                break;
+            case "parent":
+                handleUploadToMultipleCollections();
+                break;
+        }
     };
 
     return (
         <>
-            <UploadStrategyChoiceModal
+            <CollectionMappingChoiceModal
                 open={choiceModalView}
                 onClose={handleChoiceModalClose}
-                uploadToSingleCollection={handleUploadToSingleCollection}
-                uploadToMultipleCollection={handleUploadToMultipleCollections}
+                didSelect={didSelectCollectionMapping}
             />
             <UploadTypeSelector
                 show={props.uploadTypeSelectorView}
diff --git a/web/apps/photos/src/components/WatchFolder.tsx b/web/apps/photos/src/components/WatchFolder.tsx
index b5ff00b29..738bafde8 100644
--- a/web/apps/photos/src/components/WatchFolder.tsx
+++ b/web/apps/photos/src/components/WatchFolder.tsx
@@ -1,3 +1,7 @@
+import { ensureElectron } from "@/next/electron";
+import { basename } from "@/next/file";
+import type { CollectionMapping, FolderWatch } from "@/next/types/ipc";
+import { ensure } from "@/utils/ensure";
 import {
     FlexWrapper,
     HorizontalFlex,
@@ -23,31 +27,39 @@ import {
     Typography,
 } from "@mui/material";
 import { styled } from "@mui/material/styles";
-import UploadStrategyChoiceModal from "components/Upload/UploadStrategyChoiceModal";
-import { PICKED_UPLOAD_TYPE, UPLOAD_STRATEGY } from "constants/upload";
+import { CollectionMappingChoiceModal } from "components/Upload/CollectionMappingChoiceModal";
 import { t } from "i18next";
 import { AppContext } from "pages/_app";
 import React, { useContext, useEffect, useState } from "react";
-import watchFolderService from "services/watch";
-import { WatchMapping } from "types/watchFolder";
-import { getImportSuggestion } from "utils/upload";
+import watcher from "services/watch";
+import { areAllInSameDirectory } from "utils/upload";
 
 interface WatchFolderProps {
     open: boolean;
     onClose: () => void;
 }
 
+/**
+ * View the state of and manage folder watches.
+ *
+ * This is the screen that controls that "watch folder" feature in the app.
+ */
 export const WatchFolder: React.FC<WatchFolderProps> = ({ open, onClose }) => {
-    const [mappings, setMappings] = useState<WatchMapping[]>([]);
-    const [inputFolderPath, setInputFolderPath] = useState("");
+    // The folders we are watching
+    const [watches, setWatches] = useState<FolderWatch[] | undefined>();
+    // Temporarily stash the folder path while we show a choice dialog to the
+    // user to select the collection mapping.
+    const [savedFolderPath, setSavedFolderPath] = useState<
+        string | undefined
+    >();
+    // True when we're showing the choice dialog to ask the user to set the
+    // collection mapping.
     const [choiceModalOpen, setChoiceModalOpen] = useState(false);
+
     const appContext = useContext(AppContext);
 
-    const electron = globalThis.electron;
-
     useEffect(() => {
-        if (!electron) return;
-        watchFolderService.getWatchMappings().then((m) => setMappings(m));
+        watcher.getWatches().then((ws) => setWatches(ws));
     }, []);
 
     useEffect(() => {
@@ -64,69 +76,41 @@ export const WatchFolder: React.FC<WatchFolderProps> = ({ open, onClose }) => {
         for (let i = 0; i < folders.length; i++) {
             const folder: any = folders[i];
             const path = (folder.path as string).replace(/\\/g, "/");
-            if (await watchFolderService.isFolder(path)) {
-                await addFolderForWatching(path);
+            if (await ensureElectron().fs.isDir(path)) {
+                await selectCollectionMappingAndAddWatch(path);
             }
         }
     };
 
-    const addFolderForWatching = async (path: string) => {
-        if (!electron) return;
-
-        setInputFolderPath(path);
-        const files = await electron.getDirFiles(path);
-        const analysisResult = getImportSuggestion(
-            PICKED_UPLOAD_TYPE.FOLDERS,
-            files,
-        );
-        if (analysisResult.hasNestedFolders) {
-            setChoiceModalOpen(true);
+    const selectCollectionMappingAndAddWatch = async (path: string) => {
+        const filePaths = await ensureElectron().watch.findFiles(path);
+        if (areAllInSameDirectory(filePaths)) {
+            addWatch(path, "root");
         } else {
-            handleAddWatchMapping(UPLOAD_STRATEGY.SINGLE_COLLECTION, path);
+            setSavedFolderPath(path);
+            setChoiceModalOpen(true);
         }
     };
 
-    const handleAddFolderClick = async () => {
-        await handleFolderSelection();
-    };
+    const addWatch = (folderPath: string, mapping: CollectionMapping) =>
+        watcher.addWatch(folderPath, mapping).then((ws) => setWatches(ws));
 
-    const handleFolderSelection = async () => {
-        const folderPath = await watchFolderService.selectFolder();
-        if (folderPath) {
-            await addFolderForWatching(folderPath);
+    const addNewWatch = async () => {
+        const dirPath = await ensureElectron().selectDirectory();
+        if (dirPath) {
+            await selectCollectionMappingAndAddWatch(dirPath);
         }
     };
 
-    const handleAddWatchMapping = async (
-        uploadStrategy: UPLOAD_STRATEGY,
-        folderPath?: string,
-    ) => {
-        folderPath = folderPath || inputFolderPath;
-        await watchFolderService.addWatchMapping(
-            folderPath.substring(folderPath.lastIndexOf("/") + 1),
-            folderPath,
-            uploadStrategy,
-        );
-        setInputFolderPath("");
-        setMappings(await watchFolderService.getWatchMappings());
-    };
-
-    const handleRemoveWatchMapping = (mapping: WatchMapping) => {
-        watchFolderService
-            .mappingsAfterRemovingFolder(mapping.folderPath)
-            .then((ms) => setMappings(ms));
-    };
+    const removeWatch = async (watch: FolderWatch) =>
+        watcher.removeWatch(watch.folderPath).then((ws) => setWatches(ws));
 
     const closeChoiceModal = () => setChoiceModalOpen(false);
 
-    const uploadToSingleCollection = () => {
+    const addWatchWithMapping = (mapping: CollectionMapping) => {
         closeChoiceModal();
-        handleAddWatchMapping(UPLOAD_STRATEGY.SINGLE_COLLECTION);
-    };
-
-    const uploadToMultipleCollection = () => {
-        closeChoiceModal();
-        handleAddWatchMapping(UPLOAD_STRATEGY.COLLECTION_PER_FOLDER);
+        setSavedFolderPath(undefined);
+        addWatch(ensure(savedFolderPath), mapping);
     };
 
     return (
@@ -144,15 +128,8 @@ export const WatchFolder: React.FC<WatchFolderProps> = ({ open, onClose }) => {
                 </DialogTitleWithCloseButton>
                 <DialogContent sx={{ flex: 1 }}>
                     <Stack spacing={1} p={1.5} height={"100%"}>
-                        <MappingList
-                            mappings={mappings}
-                            handleRemoveWatchMapping={handleRemoveWatchMapping}
-                        />
-                        <Button
-                            fullWidth
-                            color="accent"
-                            onClick={handleAddFolderClick}
-                        >
+                        <WatchList {...{ watches, removeWatch }} />
+                        <Button fullWidth color="accent" onClick={addNewWatch}>
                             <span>+</span>
                             <span
                                 style={{
@@ -164,17 +141,39 @@ export const WatchFolder: React.FC<WatchFolderProps> = ({ open, onClose }) => {
                     </Stack>
                 </DialogContent>
             </Dialog>
-            <UploadStrategyChoiceModal
+            <CollectionMappingChoiceModal
                 open={choiceModalOpen}
                 onClose={closeChoiceModal}
-                uploadToSingleCollection={uploadToSingleCollection}
-                uploadToMultipleCollection={uploadToMultipleCollection}
+                didSelect={addWatchWithMapping}
             />
         </>
     );
 };
 
-const MappingsContainer = styled(Box)(() => ({
+interface WatchList {
+    watches: FolderWatch[];
+    removeWatch: (watch: FolderWatch) => void;
+}
+
+const WatchList: React.FC<WatchList> = ({ watches, removeWatch }) => {
+    return watches.length === 0 ? (
+        <NoWatches />
+    ) : (
+        <WatchesContainer>
+            {watches.map((watch) => {
+                return (
+                    <WatchEntry
+                        key={watch.folderPath}
+                        watch={watch}
+                        removeWatch={removeWatch}
+                    />
+                );
+            })}
+        </WatchesContainer>
+    );
+};
+
+const WatchesContainer = styled(Box)(() => ({
     height: "278px",
     overflow: "auto",
     "&::-webkit-scrollbar": {
@@ -182,47 +181,9 @@ const MappingsContainer = styled(Box)(() => ({
     },
 }));
 
-const NoMappingsContainer = styled(VerticallyCentered)({
-    textAlign: "left",
-    alignItems: "flex-start",
-    marginBottom: "32px",
-});
-
-const EntryContainer = styled(Box)({
-    marginLeft: "12px",
-    marginRight: "6px",
-    marginBottom: "12px",
-});
-
-interface MappingListProps {
-    mappings: WatchMapping[];
-    handleRemoveWatchMapping: (value: WatchMapping) => void;
-}
-
-const MappingList: React.FC<MappingListProps> = ({
-    mappings,
-    handleRemoveWatchMapping,
-}) => {
-    return mappings.length === 0 ? (
-        <NoMappingsContent />
-    ) : (
-        <MappingsContainer>
-            {mappings.map((mapping) => {
-                return (
-                    <MappingEntry
-                        key={mapping.rootFolderName}
-                        mapping={mapping}
-                        handleRemoveMapping={handleRemoveWatchMapping}
-                    />
-                );
-            })}
-        </MappingsContainer>
-    );
-};
-
-const NoMappingsContent: React.FC = () => {
+const NoWatches: React.FC = () => {
     return (
-        <NoMappingsContainer>
+        <NoWatchesContainer>
             <Stack spacing={1}>
                 <Typography variant="large" fontWeight={"bold"}>
                     {t("NO_FOLDERS_ADDED")}
@@ -243,10 +204,16 @@ const NoMappingsContent: React.FC = () => {
                     </FlexWrapper>
                 </Typography>
             </Stack>
-        </NoMappingsContainer>
+        </NoWatchesContainer>
     );
 };
 
+const NoWatchesContainer = styled(VerticallyCentered)({
+    textAlign: "left",
+    alignItems: "flex-start",
+    marginBottom: "32px",
+});
+
 const CheckmarkIcon: React.FC = () => {
     return (
         <CheckIcon
@@ -254,28 +221,20 @@ const CheckmarkIcon: React.FC = () => {
             sx={{
                 display: "inline",
                 fontSize: "15px",
-
                 color: (theme) => theme.palette.secondary.main,
             }}
         />
     );
 };
 
-interface MappingEntryProps {
-    mapping: WatchMapping;
-    handleRemoveMapping: (mapping: WatchMapping) => void;
+interface WatchEntryProps {
+    watch: FolderWatch;
+    removeWatch: (watch: FolderWatch) => void;
 }
 
-const MappingEntry: React.FC<MappingEntryProps> = ({
-    mapping,
-    handleRemoveMapping,
-}) => {
+const WatchEntry: React.FC<WatchEntryProps> = ({ watch, removeWatch }) => {
     const appContext = React.useContext(AppContext);
 
-    const stopWatching = () => {
-        handleRemoveMapping(mapping);
-    };
-
     const confirmStopWatching = () => {
         appContext.setDialogMessage({
             title: t("STOP_WATCHING_FOLDER"),
@@ -285,7 +244,7 @@ const MappingEntry: React.FC<MappingEntryProps> = ({
                 variant: "secondary",
             },
             proceed: {
-                action: stopWatching,
+                action: () => removeWatch(watch),
                 text: t("YES_STOP"),
                 variant: "critical",
             },
@@ -295,8 +254,7 @@ const MappingEntry: React.FC<MappingEntryProps> = ({
     return (
         <SpaceBetweenFlex>
             <HorizontalFlex>
-                {mapping &&
-                mapping.uploadStrategy === UPLOAD_STRATEGY.SINGLE_COLLECTION ? (
+                {watch.collectionMapping === "root" ? (
                     <Tooltip title={t("UPLOADED_TO_SINGLE_COLLECTION")}>
                         <FolderOpenIcon />
                     </Tooltip>
@@ -306,41 +264,45 @@ const MappingEntry: React.FC<MappingEntryProps> = ({
                     </Tooltip>
                 )}
                 <EntryContainer>
-                    <EntryHeading mapping={mapping} />
+                    <EntryHeading watch={watch} />
                     <Typography color="text.muted" variant="small">
-                        {mapping.folderPath}
+                        {watch.folderPath}
                     </Typography>
                 </EntryContainer>
             </HorizontalFlex>
-            <MappingEntryOptions confirmStopWatching={confirmStopWatching} />
+            <EntryOptions {...{ confirmStopWatching }} />
         </SpaceBetweenFlex>
     );
 };
 
+const EntryContainer = styled(Box)({
+    marginLeft: "12px",
+    marginRight: "6px",
+    marginBottom: "12px",
+});
+
 interface EntryHeadingProps {
-    mapping: WatchMapping;
+    watch: FolderWatch;
 }
 
-const EntryHeading: React.FC<EntryHeadingProps> = ({ mapping }) => {
-    const appContext = useContext(AppContext);
+const EntryHeading: React.FC<EntryHeadingProps> = ({ watch }) => {
+    const folderPath = watch.folderPath;
+
     return (
         <FlexWrapper gap={1}>
-            <Typography>{mapping.rootFolderName}</Typography>
-            {appContext.isFolderSyncRunning &&
-                watchFolderService.isMappingSyncInProgress(mapping) && (
-                    <CircularProgress size={12} />
-                )}
+            <Typography>{basename(folderPath)}</Typography>
+            {watcher.isSyncingFolder(folderPath) && (
+                <CircularProgress size={12} />
+            )}
         </FlexWrapper>
     );
 };
 
-interface MappingEntryOptionsProps {
+interface EntryOptionsProps {
     confirmStopWatching: () => void;
 }
 
-const MappingEntryOptions: React.FC<MappingEntryOptionsProps> = ({
-    confirmStopWatching,
-}) => {
+const EntryOptions: React.FC<EntryOptionsProps> = ({ confirmStopWatching }) => {
     return (
         <OverflowMenu
             menuPaperProps={{
diff --git a/web/apps/photos/src/constants/upload.ts b/web/apps/photos/src/constants/upload.ts
index 6d9f63d78..1f8858bc3 100644
--- a/web/apps/photos/src/constants/upload.ts
+++ b/web/apps/photos/src/constants/upload.ts
@@ -1,11 +1,6 @@
 import { ENCRYPTION_CHUNK_SIZE } from "@ente/shared/crypto/constants";
 import { FILE_TYPE } from "constants/file";
-import {
-    FileTypeInfo,
-    ImportSuggestion,
-    Location,
-    ParsedExtractedMetadata,
-} from "types/upload";
+import { FileTypeInfo, Location, ParsedExtractedMetadata } from "types/upload";
 
 // list of format that were missed by type-detection for some files.
 export const WHITELISTED_FILE_FORMATS: FileTypeInfo[] = [
@@ -111,12 +106,6 @@ export const NULL_EXTRACTED_METADATA: ParsedExtractedMetadata = {
 
 export const A_SEC_IN_MICROSECONDS = 1e6;
 
-export const DEFAULT_IMPORT_SUGGESTION: ImportSuggestion = {
-    rootFolderName: "",
-    hasNestedFolders: false,
-    hasRootLevelFileWithFolder: false,
-};
-
 export const BLACK_THUMBNAIL_BASE64 =
     "/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAEBAQEBAQEB" +
     "AQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQH/2wBDAQEBAQEBAQ" +
diff --git a/web/apps/photos/src/pages/_app.tsx b/web/apps/photos/src/pages/_app.tsx
index c31256f13..4b5fe3107 100644
--- a/web/apps/photos/src/pages/_app.tsx
+++ b/web/apps/photos/src/pages/_app.tsx
@@ -5,7 +5,7 @@ import {
     logStartupBanner,
     logUnhandledErrorsAndRejections,
 } from "@/next/log-web";
-import { AppUpdateInfo } from "@/next/types/ipc";
+import { AppUpdate } from "@/next/types/ipc";
 import {
     APPS,
     APP_TITLES,
@@ -91,8 +91,6 @@ type AppContextType = {
     closeMessageDialog: () => void;
     setDialogMessage: SetDialogBoxAttributes;
     setNotificationAttributes: SetNotificationAttributes;
-    isFolderSyncRunning: boolean;
-    setIsFolderSyncRunning: (isRunning: boolean) => void;
     watchFolderView: boolean;
     setWatchFolderView: (isOpen: boolean) => void;
     watchFolderFiles: FileList;
@@ -128,7 +126,6 @@ export default function App({ Component, pageProps }: AppProps) {
     useState<DialogBoxAttributes>(null);
     const [messageDialogView, setMessageDialogView] = useState(false);
     const [dialogBoxV2View, setDialogBoxV2View] = useState(false);
-    const [isFolderSyncRunning, setIsFolderSyncRunning] = useState(false);
     const [watchFolderView, setWatchFolderView] = useState(false);
     const [watchFolderFiles, setWatchFolderFiles] = useState<FileList>(null);
     const isMobile = useMediaQuery("(max-width:428px)");
@@ -160,9 +157,9 @@ export default function App({ Component, pageProps }: AppProps) {
         const electron = globalThis.electron;
         if (!electron) return;
 
-        const showUpdateDialog = (updateInfo: AppUpdateInfo) => {
-            if (updateInfo.autoUpdatable) {
-                setDialogMessage(getUpdateReadyToInstallMessage(updateInfo));
+        const showUpdateDialog = (update: AppUpdate) => {
+            if (update.autoUpdatable) {
+                setDialogMessage(getUpdateReadyToInstallMessage(update));
             } else {
                 setNotificationAttributes({
                     endIcon: <ArrowForward />,
@@ -170,7 +167,7 @@ export default function App({ Component, pageProps }: AppProps) {
                     message: t("UPDATE_AVAILABLE"),
                     onClick: () =>
                         setDialogMessage(
-                            getUpdateAvailableForDownloadMessage(updateInfo),
+                            getUpdateAvailableForDownloadMessage(update),
                         ),
                 });
             }
@@ -403,8 +400,6 @@ export default function App({ Component, pageProps }: AppProps) {
                         finishLoading,
                         closeMessageDialog,
                         setDialogMessage,
-                        isFolderSyncRunning,
-                        setIsFolderSyncRunning,
                         watchFolderView,
                         setWatchFolderView,
                         watchFolderFiles,
diff --git a/web/apps/photos/src/services/importService.ts b/web/apps/photos/src/services/importService.ts
deleted file mode 100644
index 6d2c46a85..000000000
--- a/web/apps/photos/src/services/importService.ts
+++ /dev/null
@@ -1,74 +0,0 @@
-import { ensureElectron } from "@/next/electron";
-import log from "@/next/log";
-import { PICKED_UPLOAD_TYPE } from "constants/upload";
-import { Collection } from "types/collection";
-import { ElectronFile, FileWithCollection } from "types/upload";
-
-interface PendingUploads {
-    files: ElectronFile[];
-    collectionName: string;
-    type: PICKED_UPLOAD_TYPE;
-}
-
-class ImportService {
-    async getPendingUploads(): Promise<PendingUploads> {
-        try {
-            const pendingUploads =
-                (await ensureElectron().getPendingUploads()) as PendingUploads;
-            return pendingUploads;
-        } catch (e) {
-            if (e?.message?.includes("ENOENT: no such file or directory")) {
-                // ignore
-            } else {
-                log.error("failed to getPendingUploads ", e);
-            }
-            return { files: [], collectionName: null, type: null };
-        }
-    }
-
-    async setToUploadCollection(collections: Collection[]) {
-        let collectionName: string = null;
-        /* collection being one suggest one of two things
-                1. Either the user has upload to a single existing collection
-                2. Created a new single collection to upload to
-                    may have had multiple folder, but chose to upload
-                    to one album
-                hence saving the collection name when upload collection count is 1
-                helps the info of user choosing this options
-                and on next upload we can directly start uploading to this collection
-            */
-        if (collections.length === 1) {
-            collectionName = collections[0].name;
-        }
-        await ensureElectron().setToUploadCollection(collectionName);
-    }
-
-    async updatePendingUploads(files: FileWithCollection[]) {
-        const filePaths = [];
-        for (const fileWithCollection of files) {
-            if (fileWithCollection.isLivePhoto) {
-                filePaths.push(
-                    (fileWithCollection.livePhotoAssets.image as ElectronFile)
-                        .path,
-                    (fileWithCollection.livePhotoAssets.video as ElectronFile)
-                        .path,
-                );
-            } else {
-                filePaths.push((fileWithCollection.file as ElectronFile).path);
-            }
-        }
-        await ensureElectron().setToUploadFiles(
-            PICKED_UPLOAD_TYPE.FILES,
-            filePaths,
-        );
-    }
-
-    async cancelRemainingUploads() {
-        const electron = ensureElectron();
-        await electron.setToUploadCollection(null);
-        await electron.setToUploadFiles(PICKED_UPLOAD_TYPE.ZIPS, []);
-        await electron.setToUploadFiles(PICKED_UPLOAD_TYPE.FILES, []);
-    }
-}
-
-export default new ImportService();
diff --git a/web/apps/photos/src/services/pending-uploads.ts b/web/apps/photos/src/services/pending-uploads.ts
new file mode 100644
index 000000000..3b219f5b0
--- /dev/null
+++ b/web/apps/photos/src/services/pending-uploads.ts
@@ -0,0 +1,42 @@
+import { ensureElectron } from "@/next/electron";
+import { Collection } from "types/collection";
+import { ElectronFile, FileWithCollection } from "types/upload";
+
+export const setToUploadCollection = async (collections: Collection[]) => {
+    let collectionName: string = null;
+    /* collection being one suggest one of two things
+                1. Either the user has upload to a single existing collection
+                2. Created a new single collection to upload to
+                    may have had multiple folder, but chose to upload
+                    to one album
+                hence saving the collection name when upload collection count is 1
+                helps the info of user choosing this options
+                and on next upload we can directly start uploading to this collection
+            */
+    if (collections.length === 1) {
+        collectionName = collections[0].name;
+    }
+    await ensureElectron().setPendingUploadCollection(collectionName);
+};
+
+export const updatePendingUploads = async (files: FileWithCollection[]) => {
+    const filePaths = [];
+    for (const fileWithCollection of files) {
+        if (fileWithCollection.isLivePhoto) {
+            filePaths.push(
+                (fileWithCollection.livePhotoAssets.image as ElectronFile).path,
+                (fileWithCollection.livePhotoAssets.video as ElectronFile).path,
+            );
+        } else {
+            filePaths.push((fileWithCollection.file as ElectronFile).path);
+        }
+    }
+    await ensureElectron().setPendingUploadFiles("files", filePaths);
+};
+
+export const cancelRemainingUploads = async () => {
+    const electron = ensureElectron();
+    await electron.setPendingUploadCollection(undefined);
+    await electron.setPendingUploadFiles("zips", []);
+    await electron.setPendingUploadFiles("files", []);
+};
diff --git a/web/apps/photos/src/services/upload/uploadManager.ts b/web/apps/photos/src/services/upload/uploadManager.ts
index d222999d8..e927d7b08 100644
--- a/web/apps/photos/src/services/upload/uploadManager.ts
+++ b/web/apps/photos/src/services/upload/uploadManager.ts
@@ -8,13 +8,16 @@ import { Events, eventBus } from "@ente/shared/events";
 import { Remote } from "comlink";
 import { UPLOAD_RESULT, UPLOAD_STAGES } from "constants/upload";
 import isElectron from "is-electron";
-import ImportService from "services/importService";
+import {
+    cancelRemainingUploads,
+    updatePendingUploads,
+} from "services/pending-uploads";
 import {
     getLocalPublicFiles,
     getPublicCollectionUID,
 } from "services/publicCollectionService";
 import { getDisableCFUploadProxyFlag } from "services/userService";
-import watchFolderService from "services/watch";
+import watcher from "services/watch";
 import { Collection } from "types/collection";
 import { EncryptedEnteFile, EnteFile } from "types/file";
 import { SetFiles } from "types/gallery";
@@ -177,7 +180,7 @@ class UploadManager {
             if (e.message === CustomError.UPLOAD_CANCELLED) {
                 if (isElectron()) {
                     this.remainingFiles = [];
-                    await ImportService.cancelRemainingUploads();
+                    await cancelRemainingUploads();
                 }
             } else {
                 log.error("uploading failed with error", e);
@@ -387,11 +390,13 @@ class UploadManager {
         uploadedFile: EncryptedEnteFile,
     ) {
         if (isElectron()) {
-            await watchFolderService.onFileUpload(
-                fileUploadResult,
-                fileWithCollection,
-                uploadedFile,
-            );
+            if (watcher.isUploadRunning()) {
+                await watcher.onFileUpload(
+                    fileUploadResult,
+                    fileWithCollection,
+                    uploadedFile,
+                );
+            }
         }
     }
 
@@ -431,12 +436,12 @@ class UploadManager {
             this.remainingFiles = this.remainingFiles.filter(
                 (file) => !areFileWithCollectionsSame(file, fileWithCollection),
             );
-            await ImportService.updatePendingUploads(this.remainingFiles);
+            await updatePendingUploads(this.remainingFiles);
         }
     }
 
     public shouldAllowNewUpload = () => {
-        return !this.uploadInProgress || watchFolderService.isUploadRunning();
+        return !this.uploadInProgress || watcher.isUploadRunning();
     };
 }
 
diff --git a/web/apps/photos/src/services/watch.ts b/web/apps/photos/src/services/watch.ts
index 2d5ef0228..703dd87ad 100644
--- a/web/apps/photos/src/services/watch.ts
+++ b/web/apps/photos/src/services/watch.ts
@@ -4,283 +4,318 @@
  */
 
 import { ensureElectron } from "@/next/electron";
+import { basename, dirname } from "@/next/file";
 import log from "@/next/log";
-import { UPLOAD_RESULT, UPLOAD_STRATEGY } from "constants/upload";
+import type {
+    CollectionMapping,
+    FolderWatch,
+    FolderWatchSyncedFile,
+} from "@/next/types/ipc";
+import { UPLOAD_RESULT } from "constants/upload";
 import debounce from "debounce";
 import uploadManager from "services/upload/uploadManager";
 import { Collection } from "types/collection";
 import { EncryptedEnteFile } from "types/file";
 import { ElectronFile, FileWithCollection } from "types/upload";
-import {
-    EventQueueItem,
-    WatchMapping,
-    WatchMappingSyncedFile,
-} from "types/watchFolder";
 import { groupFilesBasedOnCollectionID } from "utils/file";
-import { isSystemFile } from "utils/upload";
+import { isHiddenFile } from "utils/upload";
 import { removeFromCollection } from "./collectionService";
 import { getLocalFiles } from "./fileService";
 
-class WatchFolderService {
-    private eventQueue: EventQueueItem[] = [];
-    private currentEvent: EventQueueItem;
-    private currentlySyncedMapping: WatchMapping;
-    private trashingDirQueue: string[] = [];
-    private isEventRunning: boolean = false;
-    private uploadRunning: boolean = false;
+/**
+ * Watch for file system folders and automatically update the corresponding Ente
+ * collections.
+ *
+ * This class relies on APIs exposed over the Electron IPC layer, and thus only
+ * works when we're running inside our desktop app.
+ */
+class FolderWatcher {
+    /** Pending file system events that we need to process. */
+    private eventQueue: WatchEvent[] = [];
+    /** The folder watch whose event we're currently processing */
+    private activeWatch: FolderWatch | undefined;
+    /**
+     * If the file system directory corresponding to the (root) folder path of a
+     * folder watch is deleted on disk, we note down that in this queue so that
+     * we can ignore any file system events that come for it next.
+     *
+     * TODO: is this really needed? the mappings are pre-checked first.
+     */
+    private deletedFolderPaths: string[] = [];
+    /** `true` if we are using the uploader. */
+    private uploadRunning = false;
+    /** `true` if we are temporarily paused to let a user upload go through. */
+    private isPaused = false;
     private filePathToUploadedFileIDMap = new Map<string, EncryptedEnteFile>();
     private unUploadableFilePaths = new Set<string>();
-    private isPaused = false;
-    private setElectronFiles: (files: ElectronFile[]) => void;
-    private setCollectionName: (collectionName: string) => void;
+
+    /**
+     * A function to call when we want to enqueue a new upload of the given list
+     * of file paths to the given Ente collection.
+     *
+     * This is passed as a param to {@link init}.
+     */
+    private upload: (collectionName: string, filePaths: string[]) => void;
+    /**
+     * A function to call when we want to sync with the backend.
+     *
+     * This is passed as a param to {@link init}.
+     */
     private syncWithRemote: () => void;
-    private setWatchFolderServiceIsRunning: (isRunning: boolean) => void;
+
+    /** A helper function that debounces invocations of {@link runNextEvent}. */
     private debouncedRunNextEvent: () => void;
 
     constructor() {
         this.debouncedRunNextEvent = debounce(() => this.runNextEvent(), 1000);
     }
 
+    /**
+     * Initialize the watcher and start processing file system events.
+     *
+     * This is only called when we're running in the context of our desktop app.
+     *
+     * The caller provides us with the hooks we can use to actually upload the
+     * files, and to sync with remote (say after deletion).
+     */
+    init(
+        upload: (collectionName: string, filePaths: string[]) => void,
+        syncWithRemote: () => void,
+    ) {
+        this.upload = upload;
+        this.syncWithRemote = syncWithRemote;
+        this.registerListeners();
+        this.syncWithDisk();
+    }
+
+    /** `true` if we are currently using the uploader */
     isUploadRunning() {
         return this.uploadRunning;
     }
 
+    /** `true` if syncing has been temporarily paused */
     isSyncPaused() {
         return this.isPaused;
     }
 
-    async init(
-        setElectronFiles: (files: ElectronFile[]) => void,
-        setCollectionName: (collectionName: string) => void,
-        syncWithRemote: () => void,
-        setWatchFolderServiceIsRunning: (isRunning: boolean) => void,
-    ) {
-        try {
-            this.setElectronFiles = setElectronFiles;
-            this.setCollectionName = setCollectionName;
-            this.syncWithRemote = syncWithRemote;
-            this.setWatchFolderServiceIsRunning =
-                setWatchFolderServiceIsRunning;
-            this.setupWatcherFunctions();
-            await this.getAndSyncDiffOfFiles();
-        } catch (e) {
-            log.error("error while initializing watch service", e);
-        }
+    /**
+     * Temporarily pause syncing and cancel any running uploads.
+     *
+     * This frees up the uploader for handling user initated uploads.
+     */
+    pauseRunningSync() {
+        this.isPaused = true;
+        uploadManager.cancelRunningUpload();
     }
 
-    async getAndSyncDiffOfFiles() {
+    /**
+     * Resume from a temporary pause, resyncing from disk.
+     *
+     * Sibling of {@link pauseRunningSync}.
+     */
+    resumePausedSync() {
+        this.isPaused = false;
+        this.syncWithDisk();
+    }
+
+    /** Return the list of folders we are watching for changes. */
+    async getWatches(): Promise<FolderWatch[]> {
+        return await ensureElectron().watch.get();
+    }
+
+    /**
+     * Return true if we are currently syncing files that belong to the given
+     * {@link folderPath}.
+     */
+    isSyncingFolder(folderPath: string) {
+        return this.activeWatch?.folderPath == folderPath;
+    }
+
+    /**
+     * Add a new folder watch for the given root {@link folderPath}
+     *
+     * @param mapping The {@link CollectionMapping} to use to decide which
+     * collection do files belonging to nested directories go to.
+     *
+     * @returns The updated list of watches.
+     */
+    async addWatch(folderPath: string, mapping: CollectionMapping) {
+        const watches = await ensureElectron().watch.add(folderPath, mapping);
+        this.syncWithDisk();
+        return watches;
+    }
+
+    /**
+     * Remove the folder watch for the given root {@link folderPath}.
+     *
+     * @returns The updated list of watches.
+     */
+    async removeWatch(folderPath: string) {
+        return await ensureElectron().watch.remove(folderPath);
+    }
+
+    private async syncWithDisk() {
         try {
-            let mappings = await this.getWatchMappings();
-
-            if (!mappings?.length) {
-                return;
-            }
-
-            mappings = await this.filterOutDeletedMappings(mappings);
+            const watches = await this.getWatches();
+            if (!watches) return;
 
             this.eventQueue = [];
+            const events = await deduceEvents(watches);
+            log.info(`Folder watch deduced ${events.length} events`);
+            this.eventQueue = this.eventQueue.concat(events);
 
-            for (const mapping of mappings) {
-                const filesOnDisk: ElectronFile[] =
-                    await ensureElectron().getDirFiles(mapping.folderPath);
-
-                this.uploadDiffOfFiles(mapping, filesOnDisk);
-                this.trashDiffOfFiles(mapping, filesOnDisk);
-            }
+            this.debouncedRunNextEvent();
         } catch (e) {
-            log.error("error while getting and syncing diff of files", e);
+            log.error("Ignoring error while syncing watched folders", e);
         }
     }
 
-    isMappingSyncInProgress(mapping: WatchMapping) {
-        return this.currentEvent?.folderPath === mapping.folderPath;
-    }
-
-    private uploadDiffOfFiles(
-        mapping: WatchMapping,
-        filesOnDisk: ElectronFile[],
-    ) {
-        const filesToUpload = getValidFilesToUpload(filesOnDisk, mapping);
-
-        if (filesToUpload.length > 0) {
-            for (const file of filesToUpload) {
-                const event: EventQueueItem = {
-                    type: "upload",
-                    collectionName: this.getCollectionNameForMapping(
-                        mapping,
-                        file.path,
-                    ),
-                    folderPath: mapping.folderPath,
-                    files: [file],
-                };
-                this.pushEvent(event);
-            }
-        }
-    }
-
-    private trashDiffOfFiles(
-        mapping: WatchMapping,
-        filesOnDisk: ElectronFile[],
-    ) {
-        const filesToRemove = mapping.syncedFiles.filter((file) => {
-            return !filesOnDisk.find(
-                (electronFile) => electronFile.path === file.path,
-            );
-        });
-
-        if (filesToRemove.length > 0) {
-            for (const file of filesToRemove) {
-                const event: EventQueueItem = {
-                    type: "trash",
-                    collectionName: this.getCollectionNameForMapping(
-                        mapping,
-                        file.path,
-                    ),
-                    folderPath: mapping.folderPath,
-                    paths: [file.path],
-                };
-                this.pushEvent(event);
-            }
-        }
-    }
-
-    private async filterOutDeletedMappings(
-        mappings: WatchMapping[],
-    ): Promise<WatchMapping[]> {
-        const notDeletedMappings = [];
-        for (const mapping of mappings) {
-            const mappingExists = await ensureElectron().isFolder(
-                mapping.folderPath,
-            );
-            if (!mappingExists) {
-                ensureElectron().removeWatchMapping(mapping.folderPath);
-            } else {
-                notDeletedMappings.push(mapping);
-            }
-        }
-        return notDeletedMappings;
-    }
-
-    pushEvent(event: EventQueueItem) {
+    pushEvent(event: WatchEvent) {
         this.eventQueue.push(event);
+        log.info("Folder watch event", event);
         this.debouncedRunNextEvent();
     }
 
-    async pushTrashedDir(path: string) {
-        this.trashingDirQueue.push(path);
-    }
+    private registerListeners() {
+        const watch = ensureElectron().watch;
 
-    private setupWatcherFunctions() {
-        ensureElectron().registerWatcherFunctions(
-            diskFileAddedCallback,
-            diskFileRemovedCallback,
-            diskFolderRemovedCallback,
-        );
-    }
+        // [Note: File renames during folder watch]
+        //
+        // Renames come as two file system events - an `onAddFile` + an
+        // `onRemoveFile` - in an arbitrary order.
 
-    async addWatchMapping(
-        rootFolderName: string,
-        folderPath: string,
-        uploadStrategy: UPLOAD_STRATEGY,
-    ) {
-        try {
-            await ensureElectron().addWatchMapping(
-                rootFolderName,
-                folderPath,
-                uploadStrategy,
-            );
-            this.getAndSyncDiffOfFiles();
-        } catch (e) {
-            log.error("error while adding watch mapping", e);
-        }
-    }
+        watch.onAddFile((path: string, watch: FolderWatch) => {
+            this.pushEvent({
+                action: "upload",
+                collectionName: collectionNameForPath(path, watch),
+                folderPath: watch.folderPath,
+                filePath: path,
+            });
+        });
 
-    async mappingsAfterRemovingFolder(folderPath: string) {
-        await ensureElectron().removeWatchMapping(folderPath);
-        return await this.getWatchMappings();
-    }
+        watch.onRemoveFile((path: string, watch: FolderWatch) => {
+            this.pushEvent({
+                action: "trash",
+                collectionName: collectionNameForPath(path, watch),
+                folderPath: watch.folderPath,
+                filePath: path,
+            });
+        });
 
-    async getWatchMappings(): Promise<WatchMapping[]> {
-        try {
-            return (await ensureElectron().getWatchMappings()) ?? [];
-        } catch (e) {
-            log.error("error while getting watch mappings", e);
-            return [];
-        }
-    }
-
-    private setIsEventRunning(isEventRunning: boolean) {
-        this.isEventRunning = isEventRunning;
-        this.setWatchFolderServiceIsRunning(isEventRunning);
+        watch.onRemoveDir((path: string, watch: FolderWatch) => {
+            if (path == watch.folderPath) {
+                log.info(
+                    `Received file system delete event for a watched folder at ${path}`,
+                );
+                this.deletedFolderPaths.push(path);
+            }
+        });
     }
 
     private async runNextEvent() {
-        try {
-            if (
-                this.eventQueue.length === 0 ||
-                this.isEventRunning ||
-                this.isPaused
-            ) {
+        if (this.eventQueue.length == 0 || this.activeWatch || this.isPaused)
+            return;
+
+        const skip = (reason: string) => {
+            log.info(`Ignoring event since ${reason}`);
+            this.debouncedRunNextEvent();
+        };
+
+        const event = this.dequeueClubbedEvent();
+        log.info(
+            `Processing ${event.action} event for folder watch ${event.folderPath} (collectionName ${event.collectionName}, ${event.filePaths.length} files)`,
+        );
+
+        const watch = (await this.getWatches()).find(
+            (watch) => watch.folderPath == event.folderPath,
+        );
+        if (!watch) {
+            // Possibly stale
+            skip(`no folder watch for found for ${event.folderPath}`);
+            return;
+        }
+
+        if (event.action === "upload") {
+            const paths = pathsToUpload(event.filePaths, watch);
+            if (paths.length == 0) {
+                skip("none of the files need uploading");
                 return;
             }
 
-            const event = this.clubSameCollectionEvents();
-            log.info(
-                `running event type:${event.type} collectionName:${event.collectionName} folderPath:${event.folderPath} , fileCount:${event.files?.length} pathsCount: ${event.paths?.length}`,
-            );
-            const mappings = await this.getWatchMappings();
-            const mapping = mappings.find(
-                (mapping) => mapping.folderPath === event.folderPath,
-            );
-            if (!mapping) {
-                throw Error("no Mapping found for event");
-            }
-            log.info(
-                `mapping for event rootFolder: ${mapping.rootFolderName} folderPath: ${mapping.folderPath} uploadStrategy: ${mapping.uploadStrategy} syncedFilesCount: ${mapping.syncedFiles.length} ignoredFilesCount ${mapping.ignoredFiles.length}`,
-            );
-            if (event.type === "upload") {
-                event.files = getValidFilesToUpload(event.files, mapping);
-                log.info(`valid files count: ${event.files?.length}`);
-                if (event.files.length === 0) {
-                    return;
-                }
-            }
-            this.currentEvent = event;
-            this.currentlySyncedMapping = mapping;
+            // Here we pass control to the uploader. When the upload is done,
+            // the uploader will notify us by calling allFileUploadsDone.
 
-            this.setIsEventRunning(true);
-            if (event.type === "upload") {
-                this.processUploadEvent();
-            } else {
-                await this.processTrashEvent();
-                this.setIsEventRunning(false);
-                setTimeout(() => this.runNextEvent(), 0);
-            }
-        } catch (e) {
-            log.error("runNextEvent failed", e);
-        }
-    }
-
-    private async processUploadEvent() {
-        try {
+            this.activeWatch = watch;
             this.uploadRunning = true;
 
-            this.setCollectionName(this.currentEvent.collectionName);
-            this.setElectronFiles(this.currentEvent.files);
-        } catch (e) {
-            log.error("error while running next upload", e);
+            const collectionName = event.collectionName;
+            log.info(
+                `Folder watch requested upload of ${paths.length} files to collection ${collectionName}`,
+            );
+
+            this.upload(collectionName, paths);
+        } else {
+            if (this.pruneFileEventsFromDeletedFolderPaths()) {
+                skip("event was from a deleted folder path");
+                return;
+            }
+
+            const [removed, rest] = watch.syncedFiles.reduce(
+                ([removed, rest], { path }) => {
+                    (event.filePaths.includes(path) ? rest : removed).push(
+                        watch,
+                    );
+                    return [removed, rest];
+                },
+                [[], []],
+            );
+
+            this.activeWatch = watch;
+
+            await this.moveToTrash(removed);
+
+            await ensureElectron().watch.updateSyncedFiles(
+                rest,
+                watch.folderPath,
+            );
+
+            this.activeWatch = undefined;
+
+            this.debouncedRunNextEvent();
         }
     }
 
+    /**
+     * Batch the next run of events with the same action, collection and folder
+     * path into a single clubbed event that contains the list of all effected
+     * file paths from the individual events.
+     */
+    private dequeueClubbedEvent(): ClubbedWatchEvent | undefined {
+        const event = this.eventQueue.shift();
+        if (!event) return undefined;
+
+        const filePaths = [event.filePath];
+        while (
+            this.eventQueue.length > 0 &&
+            event.action === this.eventQueue[0].action &&
+            event.folderPath === this.eventQueue[0].folderPath &&
+            event.collectionName === this.eventQueue[0].collectionName
+        ) {
+            filePaths.push(this.eventQueue[0].filePath);
+            this.eventQueue.shift();
+        }
+        return { ...event, filePaths };
+    }
+
+    /**
+     * Callback invoked by the uploader whenever a file we requested to
+     * {@link upload} gets uploaded.
+     */
     async onFileUpload(
         fileUploadResult: UPLOAD_RESULT,
         fileWithCollection: FileWithCollection,
         file: EncryptedEnteFile,
     ) {
-        log.debug(() => `onFileUpload called`);
-        if (!this.isUploadRunning()) {
-            return;
-        }
         if (
             [
                 UPLOAD_RESULT.ADDED_SYMLINK,
@@ -328,191 +363,151 @@ class WatchFolderService {
         }
     }
 
+    /**
+     * Callback invoked by the uploader whenever all the files we requested to
+     * {@link upload} get uploaded.
+     */
     async allFileUploadsDone(
         filesWithCollection: FileWithCollection[],
         collections: Collection[],
     ) {
-        try {
-            log.debug(
-                () =>
-                    `allFileUploadsDone,${JSON.stringify(
-                        filesWithCollection,
-                    )} ${JSON.stringify(collections)}`,
+        const electron = ensureElectron();
+        const watch = this.activeWatch;
+
+        log.debug(() =>
+            JSON.stringify({
+                f: "watch/allFileUploadsDone",
+                filesWithCollection,
+                collections,
+                watch,
+            }),
+        );
+
+        const { syncedFiles, ignoredFiles } =
+            this.parseAllFileUploadsDone(filesWithCollection);
+
+        log.debug(() =>
+            JSON.stringify({
+                f: "watch/allFileUploadsDone",
+                syncedFiles,
+                ignoredFiles,
+            }),
+        );
+
+        if (syncedFiles.length > 0)
+            await electron.watch.updateSyncedFiles(
+                watch.syncedFiles.concat(syncedFiles),
+                watch.folderPath,
             );
-            const collection = collections.find(
-                (collection) =>
-                    collection.id === filesWithCollection[0].collectionID,
+
+        if (ignoredFiles.length > 0)
+            await electron.watch.updateIgnoredFiles(
+                watch.ignoredFiles.concat(ignoredFiles),
+                watch.folderPath,
             );
-            log.debug(() => `got collection ${!!collection}`);
-            log.debug(
-                () =>
-                    `${this.isEventRunning} ${this.currentEvent.collectionName} ${collection?.name}`,
-            );
-            if (
-                !this.isEventRunning ||
-                this.currentEvent.collectionName !== collection?.name
-            ) {
-                return;
-            }
 
-            const syncedFiles: WatchMapping["syncedFiles"] = [];
-            const ignoredFiles: WatchMapping["ignoredFiles"] = [];
-
-            for (const fileWithCollection of filesWithCollection) {
-                this.handleUploadedFile(
-                    fileWithCollection,
-                    syncedFiles,
-                    ignoredFiles,
-                );
-            }
-
-            log.debug(() => `syncedFiles ${JSON.stringify(syncedFiles)}`);
-            log.debug(() => `ignoredFiles ${JSON.stringify(ignoredFiles)}`);
-
-            if (syncedFiles.length > 0) {
-                this.currentlySyncedMapping.syncedFiles = [
-                    ...this.currentlySyncedMapping.syncedFiles,
-                    ...syncedFiles,
-                ];
-                await ensureElectron().updateWatchMappingSyncedFiles(
-                    this.currentlySyncedMapping.folderPath,
-                    this.currentlySyncedMapping.syncedFiles,
-                );
-            }
-            if (ignoredFiles.length > 0) {
-                this.currentlySyncedMapping.ignoredFiles = [
-                    ...this.currentlySyncedMapping.ignoredFiles,
-                    ...ignoredFiles,
-                ];
-                await ensureElectron().updateWatchMappingIgnoredFiles(
-                    this.currentlySyncedMapping.folderPath,
-                    this.currentlySyncedMapping.ignoredFiles,
-                );
-            }
-
-            this.runPostUploadsAction();
-        } catch (e) {
-            log.error("error while running all file uploads done", e);
-        }
-    }
-
-    private runPostUploadsAction() {
-        this.setIsEventRunning(false);
+        this.activeWatch = undefined;
         this.uploadRunning = false;
-        this.runNextEvent();
+
+        this.debouncedRunNextEvent();
     }
 
-    private handleUploadedFile(
-        fileWithCollection: FileWithCollection,
-        syncedFiles: WatchMapping["syncedFiles"],
-        ignoredFiles: WatchMapping["ignoredFiles"],
-    ) {
-        if (fileWithCollection.isLivePhoto) {
-            const imagePath = (
-                fileWithCollection.livePhotoAssets.image as ElectronFile
-            ).path;
-            const videoPath = (
-                fileWithCollection.livePhotoAssets.video as ElectronFile
-            ).path;
+    private parseAllFileUploadsDone(filesWithCollection: FileWithCollection[]) {
+        const syncedFiles: FolderWatch["syncedFiles"] = [];
+        const ignoredFiles: FolderWatch["ignoredFiles"] = [];
 
-            if (
-                this.filePathToUploadedFileIDMap.has(imagePath) &&
-                this.filePathToUploadedFileIDMap.has(videoPath)
-            ) {
-                const imageFile = {
-                    path: imagePath,
-                    uploadedFileID:
-                        this.filePathToUploadedFileIDMap.get(imagePath).id,
-                    collectionID:
-                        this.filePathToUploadedFileIDMap.get(imagePath)
-                            .collectionID,
-                };
-                const videoFile = {
-                    path: videoPath,
-                    uploadedFileID:
-                        this.filePathToUploadedFileIDMap.get(videoPath).id,
-                    collectionID:
-                        this.filePathToUploadedFileIDMap.get(videoPath)
-                            .collectionID,
-                };
-                syncedFiles.push(imageFile);
-                syncedFiles.push(videoFile);
-                log.debug(
-                    () =>
-                        `added image ${JSON.stringify(
-                            imageFile,
-                        )} and video file ${JSON.stringify(
-                            videoFile,
-                        )} to uploadedFiles`,
-                );
-            } else if (
-                this.unUploadableFilePaths.has(imagePath) &&
-                this.unUploadableFilePaths.has(videoPath)
-            ) {
-                ignoredFiles.push(imagePath);
-                ignoredFiles.push(videoPath);
-                log.debug(
-                    () =>
-                        `added image ${imagePath} and video file ${videoPath} to rejectedFiles`,
-                );
-            }
-            this.filePathToUploadedFileIDMap.delete(imagePath);
-            this.filePathToUploadedFileIDMap.delete(videoPath);
-        } else {
-            const filePath = (fileWithCollection.file as ElectronFile).path;
+        for (const fileWithCollection of filesWithCollection) {
+            if (fileWithCollection.isLivePhoto) {
+                const imagePath = (
+                    fileWithCollection.livePhotoAssets.image as ElectronFile
+                ).path;
+                const videoPath = (
+                    fileWithCollection.livePhotoAssets.video as ElectronFile
+                ).path;
 
-            if (this.filePathToUploadedFileIDMap.has(filePath)) {
-                const file = {
-                    path: filePath,
-                    uploadedFileID:
-                        this.filePathToUploadedFileIDMap.get(filePath).id,
-                    collectionID:
-                        this.filePathToUploadedFileIDMap.get(filePath)
-                            .collectionID,
-                };
-                syncedFiles.push(file);
-                log.debug(() => `added file ${JSON.stringify(file)}`);
-            } else if (this.unUploadableFilePaths.has(filePath)) {
-                ignoredFiles.push(filePath);
-                log.debug(() => `added file ${filePath} to rejectedFiles`);
+                if (
+                    this.filePathToUploadedFileIDMap.has(imagePath) &&
+                    this.filePathToUploadedFileIDMap.has(videoPath)
+                ) {
+                    const imageFile = {
+                        path: imagePath,
+                        uploadedFileID:
+                            this.filePathToUploadedFileIDMap.get(imagePath).id,
+                        collectionID:
+                            this.filePathToUploadedFileIDMap.get(imagePath)
+                                .collectionID,
+                    };
+                    const videoFile = {
+                        path: videoPath,
+                        uploadedFileID:
+                            this.filePathToUploadedFileIDMap.get(videoPath).id,
+                        collectionID:
+                            this.filePathToUploadedFileIDMap.get(videoPath)
+                                .collectionID,
+                    };
+                    syncedFiles.push(imageFile);
+                    syncedFiles.push(videoFile);
+                    log.debug(
+                        () =>
+                            `added image ${JSON.stringify(
+                                imageFile,
+                            )} and video file ${JSON.stringify(
+                                videoFile,
+                            )} to uploadedFiles`,
+                    );
+                } else if (
+                    this.unUploadableFilePaths.has(imagePath) &&
+                    this.unUploadableFilePaths.has(videoPath)
+                ) {
+                    ignoredFiles.push(imagePath);
+                    ignoredFiles.push(videoPath);
+                    log.debug(
+                        () =>
+                            `added image ${imagePath} and video file ${videoPath} to rejectedFiles`,
+                    );
+                }
+                this.filePathToUploadedFileIDMap.delete(imagePath);
+                this.filePathToUploadedFileIDMap.delete(videoPath);
+            } else {
+                const filePath = (fileWithCollection.file as ElectronFile).path;
+
+                if (this.filePathToUploadedFileIDMap.has(filePath)) {
+                    const file = {
+                        path: filePath,
+                        uploadedFileID:
+                            this.filePathToUploadedFileIDMap.get(filePath).id,
+                        collectionID:
+                            this.filePathToUploadedFileIDMap.get(filePath)
+                                .collectionID,
+                    };
+                    syncedFiles.push(file);
+                    log.debug(() => `added file ${JSON.stringify(file)}`);
+                } else if (this.unUploadableFilePaths.has(filePath)) {
+                    ignoredFiles.push(filePath);
+                    log.debug(() => `added file ${filePath} to rejectedFiles`);
+                }
+                this.filePathToUploadedFileIDMap.delete(filePath);
             }
-            this.filePathToUploadedFileIDMap.delete(filePath);
         }
+
+        return { syncedFiles, ignoredFiles };
     }
 
-    private async processTrashEvent() {
-        try {
-            if (this.checkAndIgnoreIfFileEventsFromTrashedDir()) {
-                return;
-            }
+    private pruneFileEventsFromDeletedFolderPaths() {
+        const deletedFolderPath = this.deletedFolderPaths.shift();
+        if (!deletedFolderPath) return false;
 
-            const { paths } = this.currentEvent;
-            const filePathsToRemove = new Set(paths);
-
-            const files = this.currentlySyncedMapping.syncedFiles.filter(
-                (file) => filePathsToRemove.has(file.path),
-            );
-
-            await this.trashByIDs(files);
-
-            this.currentlySyncedMapping.syncedFiles =
-                this.currentlySyncedMapping.syncedFiles.filter(
-                    (file) => !filePathsToRemove.has(file.path),
-                );
-            await ensureElectron().updateWatchMappingSyncedFiles(
-                this.currentlySyncedMapping.folderPath,
-                this.currentlySyncedMapping.syncedFiles,
-            );
-        } catch (e) {
-            log.error("error while running next trash", e);
-        }
+        this.eventQueue = this.eventQueue.filter(
+            (event) => !event.filePath.startsWith(deletedFolderPath),
+        );
+        return true;
     }
 
-    private async trashByIDs(toTrashFiles: WatchMapping["syncedFiles"]) {
+    private async moveToTrash(syncedFiles: FolderWatch["syncedFiles"]) {
         try {
             const files = await getLocalFiles();
-            const toTrashFilesMap = new Map<number, WatchMappingSyncedFile>();
-            for (const file of toTrashFiles) {
+            const toTrashFilesMap = new Map<number, FolderWatchSyncedFile>();
+            for (const file of syncedFiles) {
                 toTrashFilesMap.set(file.uploadedFileID, file);
             }
             const filesToTrash = files.filter((file) => {
@@ -537,204 +532,116 @@ class WatchFolderService {
             log.error("error while trashing by IDs", e);
         }
     }
-
-    private checkAndIgnoreIfFileEventsFromTrashedDir() {
-        if (this.trashingDirQueue.length !== 0) {
-            this.ignoreFileEventsFromTrashedDir(this.trashingDirQueue[0]);
-            this.trashingDirQueue.shift();
-            return true;
-        }
-        return false;
-    }
-
-    private ignoreFileEventsFromTrashedDir(trashingDir: string) {
-        this.eventQueue = this.eventQueue.filter((event) =>
-            event.paths.every((path) => !path.startsWith(trashingDir)),
-        );
-    }
-
-    async getCollectionNameAndFolderPath(filePath: string) {
-        try {
-            const mappings = await this.getWatchMappings();
-
-            const mapping = mappings.find(
-                (mapping) =>
-                    filePath.length > mapping.folderPath.length &&
-                    filePath.startsWith(mapping.folderPath) &&
-                    filePath[mapping.folderPath.length] === "/",
-            );
-
-            if (!mapping) {
-                throw Error(`no mapping found`);
-            }
-
-            return {
-                collectionName: this.getCollectionNameForMapping(
-                    mapping,
-                    filePath,
-                ),
-                folderPath: mapping.folderPath,
-            };
-        } catch (e) {
-            log.error("error while getting collection name", e);
-        }
-    }
-
-    private getCollectionNameForMapping(
-        mapping: WatchMapping,
-        filePath: string,
-    ) {
-        return mapping.uploadStrategy === UPLOAD_STRATEGY.COLLECTION_PER_FOLDER
-            ? getParentFolderName(filePath)
-            : mapping.rootFolderName;
-    }
-
-    async selectFolder(): Promise<string> {
-        try {
-            const folderPath = await ensureElectron().selectDirectory();
-            return folderPath;
-        } catch (e) {
-            log.error("error while selecting folder", e);
-        }
-    }
-
-    // Batches all the files to be uploaded (or trashed) from the
-    // event queue of same collection as the next event
-    private clubSameCollectionEvents(): EventQueueItem {
-        const event = this.eventQueue.shift();
-        while (
-            this.eventQueue.length > 0 &&
-            event.collectionName === this.eventQueue[0].collectionName &&
-            event.type === this.eventQueue[0].type
-        ) {
-            if (event.type === "trash") {
-                event.paths = [...event.paths, ...this.eventQueue[0].paths];
-            } else {
-                event.files = [...event.files, ...this.eventQueue[0].files];
-            }
-            this.eventQueue.shift();
-        }
-        return event;
-    }
-
-    async isFolder(folderPath: string) {
-        try {
-            const isFolder = await ensureElectron().isFolder(folderPath);
-            return isFolder;
-        } catch (e) {
-            log.error("error while checking if folder exists", e);
-        }
-    }
-
-    pauseRunningSync() {
-        this.isPaused = true;
-        uploadManager.cancelRunningUpload();
-    }
-
-    resumePausedSync() {
-        this.isPaused = false;
-        this.getAndSyncDiffOfFiles();
-    }
 }
 
-const watchFolderService = new WatchFolderService();
+/** The singleton instance of the {@link FolderWatcher}. */
+const watcher = new FolderWatcher();
 
-export default watchFolderService;
+export default watcher;
 
-const getParentFolderName = (filePath: string) => {
-    const folderPath = filePath.substring(0, filePath.lastIndexOf("/"));
-    const folderName = folderPath.substring(folderPath.lastIndexOf("/") + 1);
-    return folderName;
+/**
+ * A file system watch event encapsulates a change that has occurred on disk
+ * that needs us to take some action within Ente to synchronize with the user's
+ * Ente collections.
+ *
+ * Events get added in two ways:
+ *
+ * - When the app starts, it reads the current state of files on disk and
+ *   compares that with its last known state to determine what all events it
+ *   missed. This is easier than it sounds as we have only two events: add and
+ *   remove.
+ *
+ * - When the app is running, it gets live notifications from our file system
+ *   watcher (from the Node.js layer) about changes that have happened on disk,
+ *   which the app then enqueues onto the event queue if they pertain to the
+ *   files we're interested in.
+ */
+interface WatchEvent {
+    /** The action to take */
+    action: "upload" | "trash";
+    /** The path of the root folder corresponding to the {@link FolderWatch}. */
+    folderPath: string;
+    /** The name of the Ente collection the file belongs to. */
+    collectionName: string;
+    /** The absolute path to the file under consideration. */
+    filePath: string;
+}
+
+/**
+ * A composite of multiple {@link WatchEvent}s that only differ in their
+ * {@link filePath}.
+ *
+ * When processing events, we combine a run of events with the same
+ * {@link action}, {@link folderPath} and {@link collectionName}. This allows us
+ * to process all the affected {@link filePaths} in one shot.
+ */
+type ClubbedWatchEvent = Omit<WatchEvent, "filePath"> & {
+    filePaths: string[];
 };
 
-async function diskFileAddedCallback(file: ElectronFile) {
-    try {
-        const collectionNameAndFolderPath =
-            await watchFolderService.getCollectionNameAndFolderPath(file.path);
+/**
+ * Determine which events we need to process to synchronize the watched on-disk
+ * folders to their corresponding collections.
+ */
+const deduceEvents = async (watches: FolderWatch[]): Promise<WatchEvent[]> => {
+    const electron = ensureElectron();
+    const events: WatchEvent[] = [];
 
-        if (!collectionNameAndFolderPath) {
-            return;
-        }
+    for (const watch of watches) {
+        const folderPath = watch.folderPath;
 
-        const { collectionName, folderPath } = collectionNameAndFolderPath;
+        const filePaths = await electron.watch.findFiles(folderPath);
 
-        const event: EventQueueItem = {
-            type: "upload",
-            collectionName,
-            folderPath,
-            files: [file],
-        };
-        watchFolderService.pushEvent(event);
-        log.info(
-            `added (upload) to event queue, collectionName:${event.collectionName} folderPath:${event.folderPath}, filesCount: ${event.files.length}`,
-        );
-    } catch (e) {
-        log.error("error while calling diskFileAddedCallback", e);
+        // Files that are on disk but not yet synced.
+        for (const filePath of pathsToUpload(filePaths, watch))
+            events.push({
+                action: "upload",
+                folderPath,
+                collectionName: collectionNameForPath(filePath, watch),
+                filePath,
+            });
+
+        // Previously synced files that are no longer on disk.
+        for (const filePath of pathsToRemove(filePaths, watch))
+            events.push({
+                action: "trash",
+                folderPath,
+                collectionName: collectionNameForPath(filePath, watch),
+                filePath,
+            });
     }
-}
 
-async function diskFileRemovedCallback(filePath: string) {
-    try {
-        const collectionNameAndFolderPath =
-            await watchFolderService.getCollectionNameAndFolderPath(filePath);
+    return events;
+};
 
-        if (!collectionNameAndFolderPath) {
-            return;
-        }
+/**
+ * Filter out hidden files and previously synced or ignored paths from
+ * {@link paths} to get the list of paths that need to be uploaded to the Ente
+ * collection.
+ */
+const pathsToUpload = (paths: string[], watch: FolderWatch) =>
+    paths
+        // Filter out hidden files (files whose names begins with a dot)
+        .filter((path) => !isHiddenFile(path))
+        // Files that are on disk but not yet synced or ignored.
+        .filter((path) => !isSyncedOrIgnoredPath(path, watch));
 
-        const { collectionName, folderPath } = collectionNameAndFolderPath;
+/**
+ * Return the paths to previously synced files that are no longer on disk and so
+ * must be removed from the Ente collection.
+ */
+const pathsToRemove = (paths: string[], watch: FolderWatch) =>
+    watch.syncedFiles
+        .map((f) => f.path)
+        .filter((path) => !paths.includes(path));
 
-        const event: EventQueueItem = {
-            type: "trash",
-            collectionName,
-            folderPath,
-            paths: [filePath],
-        };
-        watchFolderService.pushEvent(event);
-        log.info(
-            `added (trash) to event queue collectionName:${event.collectionName} folderPath:${event.folderPath} , pathsCount: ${event.paths.length}`,
-        );
-    } catch (e) {
-        log.error("error while calling diskFileRemovedCallback", e);
-    }
-}
+const isSyncedOrIgnoredPath = (path: string, watch: FolderWatch) =>
+    watch.ignoredFiles.includes(path) ||
+    watch.syncedFiles.find((f) => f.path === path);
 
-async function diskFolderRemovedCallback(folderPath: string) {
-    try {
-        const mappings = await watchFolderService.getWatchMappings();
-        const mapping = mappings.find(
-            (mapping) => mapping.folderPath === folderPath,
-        );
-        if (!mapping) {
-            log.info(`folder not found in mappings, ${folderPath}`);
-            throw Error(`Watch mapping not found`);
-        }
-        watchFolderService.pushTrashedDir(folderPath);
-        log.info(`added trashedDir, ${folderPath}`);
-    } catch (e) {
-        log.error("error while calling diskFolderRemovedCallback", e);
-    }
-}
+const collectionNameForPath = (path: string, watch: FolderWatch) =>
+    watch.collectionMapping == "root"
+        ? dirname(watch.folderPath)
+        : parentDirectoryName(path);
 
-export function getValidFilesToUpload(
-    files: ElectronFile[],
-    mapping: WatchMapping,
-) {
-    const uniqueFilePaths = new Set<string>();
-    return files.filter((file) => {
-        if (!isSystemFile(file) && !isSyncedOrIgnoredFile(file, mapping)) {
-            if (!uniqueFilePaths.has(file.path)) {
-                uniqueFilePaths.add(file.path);
-                return true;
-            }
-        }
-        return false;
-    });
-}
-
-function isSyncedOrIgnoredFile(file: ElectronFile, mapping: WatchMapping) {
-    return (
-        mapping.ignoredFiles.includes(file.path) ||
-        mapping.syncedFiles.find((f) => f.path === file.path)
-    );
-}
+const parentDirectoryName = (path: string) => basename(dirname(path));
diff --git a/web/apps/photos/src/types/upload/index.ts b/web/apps/photos/src/types/upload/index.ts
index 3deab0ed7..72eef39f6 100644
--- a/web/apps/photos/src/types/upload/index.ts
+++ b/web/apps/photos/src/types/upload/index.ts
@@ -156,13 +156,6 @@ export interface ParsedExtractedMetadata {
     height: number;
 }
 
-// This is used to prompt the user the make upload strategy choice
-export interface ImportSuggestion {
-    rootFolderName: string;
-    hasNestedFolders: boolean;
-    hasRootLevelFileWithFolder: boolean;
-}
-
 export interface PublicUploadProps {
     token: string;
     passwordToken: string;
diff --git a/web/apps/photos/src/types/watchFolder/index.ts b/web/apps/photos/src/types/watchFolder/index.ts
deleted file mode 100644
index bd55704de..000000000
--- a/web/apps/photos/src/types/watchFolder/index.ts
+++ /dev/null
@@ -1,24 +0,0 @@
-import { UPLOAD_STRATEGY } from "constants/upload";
-import { ElectronFile } from "types/upload";
-
-export interface WatchMappingSyncedFile {
-    path: string;
-    uploadedFileID: number;
-    collectionID: number;
-}
-
-export interface WatchMapping {
-    rootFolderName: string;
-    folderPath: string;
-    uploadStrategy: UPLOAD_STRATEGY;
-    syncedFiles: WatchMappingSyncedFile[];
-    ignoredFiles: string[];
-}
-
-export interface EventQueueItem {
-    type: "upload" | "trash";
-    folderPath: string;
-    collectionName?: string;
-    paths?: string[];
-    files?: ElectronFile[];
-}
diff --git a/web/apps/photos/src/utils/storage/mlIDbStorage.ts b/web/apps/photos/src/utils/storage/mlIDbStorage.ts
index 6dccbb89d..40e6dad66 100644
--- a/web/apps/photos/src/utils/storage/mlIDbStorage.ts
+++ b/web/apps/photos/src/utils/storage/mlIDbStorage.ts
@@ -97,10 +97,8 @@ class MLIDbStorage {
                         wasMLSearchEnabled = searchConfig.enabled;
                     }
                 } catch (e) {
-                    log.info(
-                        "Ignoring likely harmless error while trying to determine ML search status during migration",
-                        e,
-                    );
+                    // The configs store might not exist (e.g. during logout).
+                    // Ignore.
                 }
                 log.info(
                     `Previous ML database v${oldVersion} had ML search ${wasMLSearchEnabled ? "enabled" : "disabled"}`,
diff --git a/web/apps/photos/src/utils/ui/index.tsx b/web/apps/photos/src/utils/ui/index.tsx
index 1b01116d3..8f4895ead 100644
--- a/web/apps/photos/src/utils/ui/index.tsx
+++ b/web/apps/photos/src/utils/ui/index.tsx
@@ -1,5 +1,5 @@
 import { ensureElectron } from "@/next/electron";
-import { AppUpdateInfo } from "@/next/types/ipc";
+import { AppUpdate } from "@/next/types/ipc";
 import { logoutUser } from "@ente/accounts/services/user";
 import { DialogBoxAttributes } from "@ente/shared/components/DialogBox/types";
 import AutoAwesomeOutlinedIcon from "@mui/icons-material/AutoAwesomeOutlined";
@@ -55,7 +55,7 @@ export const getTrashFileMessage = (deleteFileHelper): DialogBoxAttributes => ({
 
 export const getUpdateReadyToInstallMessage = ({
     version,
-}: AppUpdateInfo): DialogBoxAttributes => ({
+}: AppUpdate): DialogBoxAttributes => ({
     icon: <AutoAwesomeOutlinedIcon />,
     title: t("UPDATE_AVAILABLE"),
     content: t("UPDATE_INSTALLABLE_MESSAGE"),
@@ -73,7 +73,7 @@ export const getUpdateReadyToInstallMessage = ({
 
 export const getUpdateAvailableForDownloadMessage = ({
     version,
-}: AppUpdateInfo): DialogBoxAttributes => ({
+}: AppUpdate): DialogBoxAttributes => ({
     icon: <AutoAwesomeOutlinedIcon />,
     title: t("UPDATE_AVAILABLE"),
     content: t("UPDATE_AVAILABLE_MESSAGE"),
diff --git a/web/apps/photos/src/utils/upload/index.ts b/web/apps/photos/src/utils/upload/index.ts
index 643c931fe..4e6d216cf 100644
--- a/web/apps/photos/src/utils/upload/index.ts
+++ b/web/apps/photos/src/utils/upload/index.ts
@@ -1,18 +1,10 @@
+import { basename, dirname } from "@/next/file";
 import { FILE_TYPE } from "constants/file";
-import {
-    A_SEC_IN_MICROSECONDS,
-    DEFAULT_IMPORT_SUGGESTION,
-    PICKED_UPLOAD_TYPE,
-} from "constants/upload";
+import { A_SEC_IN_MICROSECONDS, PICKED_UPLOAD_TYPE } from "constants/upload";
 import isElectron from "is-electron";
 import { exportMetadataDirectoryName } from "services/export";
 import { EnteFile } from "types/file";
-import {
-    ElectronFile,
-    FileWithCollection,
-    ImportSuggestion,
-    Metadata,
-} from "types/upload";
+import { ElectronFile, FileWithCollection, Metadata } from "types/upload";
 
 const TYPE_JSON = "json";
 const DEDUPE_COLLECTION = new Set(["icloud library", "icloudlibrary"]);
@@ -110,15 +102,36 @@ export function areFileWithCollectionsSame(
     return firstFile.localID === secondFile.localID;
 }
 
+/**
+ * Return true if all the paths in the given list are items that belong to the
+ * same (arbitrary) directory.
+ *
+ * Empty list of paths is considered to be in the same directory.
+ */
+export const areAllInSameDirectory = (paths: string[]) =>
+    new Set(paths.map(dirname)).size == 1;
+
+// This is used to prompt the user the make upload strategy choice
+export interface ImportSuggestion {
+    rootFolderName: string;
+    hasNestedFolders: boolean;
+    hasRootLevelFileWithFolder: boolean;
+}
+
+export const DEFAULT_IMPORT_SUGGESTION: ImportSuggestion = {
+    rootFolderName: "",
+    hasNestedFolders: false,
+    hasRootLevelFileWithFolder: false,
+};
+
 export function getImportSuggestion(
     uploadType: PICKED_UPLOAD_TYPE,
-    toUploadFiles: File[] | ElectronFile[],
+    paths: string[],
 ): ImportSuggestion {
     if (isElectron() && uploadType === PICKED_UPLOAD_TYPE.FILES) {
         return DEFAULT_IMPORT_SUGGESTION;
     }
 
-    const paths: string[] = toUploadFiles.map((file) => file["path"]);
     const getCharCount = (str: string) => (str.match(/\//g) ?? []).length;
     paths.sort((path1, path2) => getCharCount(path1) - getCharCount(path2));
     const firstPath = paths[0];
@@ -209,3 +222,10 @@ export function filterOutSystemFiles(files: File[] | ElectronFile[]) {
 export function isSystemFile(file: File | ElectronFile) {
     return file.name.startsWith(".");
 }
+
+/**
+ * Return true if the file at the given {@link path} is hidden.
+ *
+ * Hidden files are those whose names begin with a "." (dot).
+ */
+export const isHiddenFile = (path: string) => basename(path).startsWith(".");
diff --git a/web/apps/photos/tests/zip-file-reading.test.ts b/web/apps/photos/tests/zip-file-reading.test.ts
index 6ac20bfee..07d70f067 100644
--- a/web/apps/photos/tests/zip-file-reading.test.ts
+++ b/web/apps/photos/tests/zip-file-reading.test.ts
@@ -96,7 +96,7 @@ export const testZipWithRootFileReadingTest = async () => {
 
         const importSuggestion = getImportSuggestion(
             PICKED_UPLOAD_TYPE.ZIPS,
-            files,
+            files.map((file) => file["path"]),
         );
         if (!importSuggestion.rootFolderName) {
             throw Error(
diff --git a/web/packages/next/file.ts b/web/packages/next/file.ts
index fae9a6d00..83b20f2ec 100644
--- a/web/packages/next/file.ts
+++ b/web/packages/next/file.ts
@@ -17,8 +17,12 @@ type FileNameComponents = [name: string, extension: string | undefined];
  */
 export const nameAndExtension = (fileName: string): FileNameComponents => {
     const i = fileName.lastIndexOf(".");
+    // No extension
     if (i == -1) return [fileName, undefined];
-    else return [fileName.slice(0, i), fileName.slice(i + 1)];
+    // A hidden file without an extension, e.g. ".gitignore"
+    if (i == 0) return [fileName, undefined];
+    // Both components present, just omit the dot.
+    return [fileName.slice(0, i), fileName.slice(i + 1)];
 };
 
 /**
@@ -29,6 +33,39 @@ export const nameAndExtension = (fileName: string): FileNameComponents => {
 export const fileNameFromComponents = (components: FileNameComponents) =>
     components.filter((x) => !!x).join(".");
 
+/**
+ * Return the file name portion from the given {@link path}.
+ *
+ * This tries to emulate the UNIX `basename` command. In particular, any
+ * trailing slashes on the path are trimmed, so this function can be used to get
+ * the name of the directory too.
+ *
+ * The path is assumed to use POSIX separators ("/").
+ */
+export const basename = (path: string) => {
+    const pathComponents = path.split("/");
+    for (let i = pathComponents.length - 1; i >= 0; i--)
+        if (pathComponents[i] !== "") return pathComponents[i];
+    return path;
+};
+
+/**
+ * Return the directory portion from the given {@link path}.
+ *
+ * This tries to emulate the UNIX `dirname` command. In particular, any trailing
+ * slashes on the path are trimmed, so this function can be used to get the path
+ * leading up to a directory too.
+ *
+ * The path is assumed to use POSIX separators ("/").
+ */
+export const dirname = (path: string) => {
+    const pathComponents = path.split("/");
+    while (pathComponents.pop() == "") {
+        /* no-op */
+    }
+    return pathComponents.join("/");
+};
+
 export function getFileNameSize(file: File | ElectronFile) {
     return `${file.name}_${convertBytesToHumanReadable(file.size)}`;
 }
diff --git a/web/packages/next/types/ipc.ts b/web/packages/next/types/ipc.ts
index 85986b639..0628bb0ca 100644
--- a/web/packages/next/types/ipc.ts
+++ b/web/packages/next/types/ipc.ts
@@ -5,22 +5,6 @@
 
 import type { ElectronFile } from "./file";
 
-export interface AppUpdateInfo {
-    autoUpdatable: boolean;
-    version: string;
-}
-
-export enum FILE_PATH_TYPE {
-    FILES = "files",
-    ZIPS = "zips",
-}
-
-export enum PICKED_UPLOAD_TYPE {
-    FILES = "files",
-    FOLDERS = "folders",
-    ZIPS = "zips",
-}
-
 /**
  * Extra APIs provided by our Node.js layer when our code is running inside our
  * desktop (Electron) app.
@@ -111,7 +95,7 @@ export interface Electron {
      * Note: Setting a callback clears any previous callbacks.
      */
     onAppUpdateAvailable: (
-        cb?: ((updateInfo: AppUpdateInfo) => void) | undefined,
+        cb?: ((update: AppUpdate) => void) | undefined,
     ) => void;
 
     /**
@@ -199,6 +183,12 @@ export interface Electron {
          * @param contents The string contents to write.
          */
         writeFile: (path: string, contents: string) => Promise<void>;
+
+        /**
+         * Return true if there is an item at {@link dirPath}, and it is as
+         * directory.
+         */
+        isDir: (dirPath: string) => Promise<boolean>;
     };
 
     /*
@@ -284,73 +274,211 @@ export interface Electron {
 
     // - Watch
 
-    registerWatcherFunctions: (
-        addFile: (file: ElectronFile) => Promise<void>,
-        removeFile: (path: string) => Promise<void>,
-        removeFolder: (folderPath: string) => Promise<void>,
-    ) => void;
+    /**
+     * Interface with the file system watcher running in our Node.js layer.
+     *
+     * [Note: Folder vs Directory in the context of FolderWatch-es]
+     *
+     * A note on terminology: The word "folder" is used to the top level root
+     * folder for which a {@link FolderWatch} has been added. This folder is
+     * also in 1-1 correspondence to be a directory on the user's disk. It can
+     * have other, nested directories too (which may or may not be getting
+     * mapped to separate Ente collections), but we'll not refer to these nested
+     * directories as folders - only the root of the tree, which the user
+     * dragged/dropped or selected to set up the folder watch, will be referred
+     * to as a folder when naming things.
+     */
+    watch: {
+        /**
+         * Return the list of folder watches, pruning non-existing directories.
+         *
+         * The list of folder paths (and auxillary details) is persisted in the
+         * Node.js layer. The implementation of this function goes through the
+         * list, permanently removes any watches whose on-disk directory is no
+         * longer present, and returns this pruned list of watches.
+         */
+        get: () => Promise<FolderWatch[]>;
 
-    addWatchMapping: (
-        collectionName: string,
-        folderPath: string,
-        uploadStrategy: number,
-    ) => Promise<void>;
+        /**
+         * Add a new folder watch for the given {@link folderPath}.
+         *
+         * This adds a new entry in the list of watches (persisting them on
+         * disk), and also starts immediately observing for file system events
+         * that happen within {@link folderPath}.
+         *
+         * @param collectionMapping Determines how nested directories (if any)
+         * get mapped to Ente collections.
+         *
+         * @returns The updated list of watches.
+         */
+        add: (
+            folderPath: string,
+            collectionMapping: CollectionMapping,
+        ) => Promise<FolderWatch[]>;
 
-    removeWatchMapping: (folderPath: string) => Promise<void>;
+        /**
+         * Remove the pre-existing watch for the given {@link folderPath}.
+         *
+         * Persist this removal, and also stop listening for file system events
+         * that happen within the {@link folderPath}.
+         *
+         * @returns The updated list of watches.
+         */
+        remove: (folderPath: string) => Promise<FolderWatch[]>;
 
-    getWatchMappings: () => Promise<FolderWatch[]>;
+        /**
+         * Update the list of synced files for the folder watch associated
+         * with the given {@link folderPath}.
+         */
+        updateSyncedFiles: (
+            syncedFiles: FolderWatch["syncedFiles"],
+            folderPath: string,
+        ) => Promise<void>;
 
-    updateWatchMappingSyncedFiles: (
-        folderPath: string,
-        files: FolderWatch["syncedFiles"],
-    ) => Promise<void>;
+        /**
+         * Update the list of ignored file paths for the folder watch
+         * associated with the given {@link folderPath}.
+         */
+        updateIgnoredFiles: (
+            ignoredFiles: FolderWatch["ignoredFiles"],
+            folderPath: string,
+        ) => Promise<void>;
 
-    updateWatchMappingIgnoredFiles: (
-        folderPath: string,
-        files: FolderWatch["ignoredFiles"],
-    ) => Promise<void>;
+        /**
+         * Register the function to invoke when a file is added in one of the
+         * folders we are watching.
+         *
+         * The callback function is passed the path to the file that was added,
+         * and the folder watch it was associated with.
+         *
+         * The path is guaranteed to use POSIX separators ('/').
+         */
+        onAddFile: (f: (path: string, watch: FolderWatch) => void) => void;
 
-    // - FS legacy
-    isFolder: (dirPath: string) => Promise<boolean>;
+        /**
+         * Register the function to invoke when a file is removed in one of the
+         * folders we are watching.
+         *
+         * The callback function is passed the path to the file that was
+         * removed, and the folder watch it was associated with.
+         *
+         * The path is guaranteed to use POSIX separators ('/').
+         */
+        onRemoveFile: (f: (path: string, watch: FolderWatch) => void) => void;
+
+        /**
+         * Register the function to invoke when a directory is removed in one of
+         * the folders we are watching.
+         *
+         * The callback function is passed the path to the directory that was
+         * removed, and the folder watch it was associated with.
+         *
+         * The path is guaranteed to use POSIX separators ('/').
+         */
+        onRemoveDir: (f: (path: string, watch: FolderWatch) => void) => void;
+
+        /**
+         * Return the paths of all the files under the given folder.
+         *
+         * This function walks the directory tree starting at {@link folderPath}
+         * and returns a list of the absolute paths of all the files that exist
+         * therein. It will recursively traverse into nested directories, and
+         * return the absolute paths of the files there too.
+         *
+         * The returned paths are guaranteed to use POSIX separators ('/').
+         */
+        findFiles: (folderPath: string) => Promise<string[]>;
+    };
 
     // - Upload
 
-    getPendingUploads: () => Promise<{
-        files: ElectronFile[];
-        collectionName: string;
-        type: string;
-    }>;
-    setToUploadFiles: (
-        /** TODO(MR): This is the actual type */
-        // type: FILE_PATH_TYPE,
-        type: PICKED_UPLOAD_TYPE,
+    /**
+     * Return any pending uploads that were previously enqueued but haven't yet
+     * been completed.
+     *
+     * The state of pending uploads is persisted in the Node.js layer.
+     *
+     * Note that we might have both outstanding zip and regular file uploads at
+     * the same time. In such cases, the zip file ones get precedence.
+     */
+    pendingUploads: () => Promise<PendingUploads | undefined>;
+
+    /**
+     * Set or clear the name of the collection where the pending upload is
+     * directed to.
+     */
+    setPendingUploadCollection: (collectionName: string) => Promise<void>;
+
+    /**
+     * Update the list of files (of {@link type}) associated with the pending
+     * upload.
+     */
+    setPendingUploadFiles: (
+        type: PendingUploads["type"],
         filePaths: string[],
     ) => Promise<void>;
+
+    // -
+
     getElectronFilesFromGoogleZip: (
         filePath: string,
     ) => Promise<ElectronFile[]>;
-    setToUploadCollection: (collectionName: string) => Promise<void>;
     getDirFiles: (dirPath: string) => Promise<ElectronFile[]>;
 }
 
+/**
+ * Data passed across the IPC bridge when an app update is available.
+ */
+export interface AppUpdate {
+    /** `true` if the user automatically update to this (new) version */
+    autoUpdatable: boolean;
+    /** The new version that is available */
+    version: string;
+}
+
 /**
  * A top level folder that was selected by the user for watching.
  *
  * The user can set up multiple such watches. Each of these can in turn be
- * syncing multiple on disk folders to one or more (dependening on the
- * {@link uploadStrategy}) Ente albums.
+ * syncing multiple on disk folders to one or more Ente collections (depending
+ * on the value of {@link collectionMapping}).
  *
  * This type is passed across the IPC boundary. It is persisted on the Node.js
  * side.
  */
 export interface FolderWatch {
-    rootFolderName: string;
-    uploadStrategy: number;
+    /**
+     * Specify if nested files should all be mapped to the same single root
+     * collection, or if there should be a collection per directory that has
+     * files. @see {@link CollectionMapping}.
+     */
+    collectionMapping: CollectionMapping;
+    /**
+     * The path to the (root) folder we are watching.
+     */
     folderPath: string;
+    /**
+     * Files that have already been uploaded.
+     */
     syncedFiles: FolderWatchSyncedFile[];
+    /**
+     * Files (paths) that should be ignored when uploading.
+     */
     ignoredFiles: string[];
 }
 
+/**
+ * The ways in which directories are mapped to collection.
+ *
+ * This comes into play when we have nested directories that we are trying to
+ * upload or watch on the user's local file system.
+ */
+export type CollectionMapping =
+    /** All files go into a single collection named after the root directory. */
+    | "root"
+    /** Each file goes to a collection named after its parent directory. */
+    | "parent";
+
 /**
  * An on-disk file that was synced as part of a folder watch.
  */
@@ -359,3 +487,16 @@ export interface FolderWatchSyncedFile {
     uploadedFileID: number;
     collectionID: number;
 }
+
+/**
+ * When the user starts an upload, we remember the files they'd selected or drag
+ * and dropped so that we can resume (if needed) when the app restarts after
+ * being stopped in the middle of the uploads.
+ */
+export interface PendingUploads {
+    /** The collection to which we're uploading */
+    collectionName: string;
+    /* The upload can be either of a Google Takeout zip, or regular files */
+    type: "files" | "zips";
+    files: ElectronFile[];
+}
diff --git a/web/packages/utils/ensure.ts b/web/packages/utils/ensure.ts
new file mode 100644
index 000000000..2e8f9a213
--- /dev/null
+++ b/web/packages/utils/ensure.ts
@@ -0,0 +1,7 @@
+/**
+ * Throw an exception if the given value is undefined.
+ */
+export const ensure = <T>(v: T | undefined): T => {
+    if (v === undefined) throw new Error("Required value was not found");
+    return v;
+};