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perf: replace cidranger with bart for significant performance improvements (#675)

* feat: replace cidranger with bart improving performance by 3-20x

Signed-off-by: Jason Cameron <git@jasoncameron.dev>

* perf: replace cidranger with bart for IP range checking

- Replace cidranger.Ranger with bart.Lite in RemoteAddrChecker
- Use netip.ParsePrefix instead of net.ParseCIDR for modern IP handling
- Improve performance: 3-20x faster lookups with zero heap allocations
- Update imports to use github.com/gaissmai/bart and net/netip
- Remove cidranger dependency from go.mod

Benchmark results:
- IPv4 lookups: 4x faster (15.58ns vs 63.25ns, 0 vs 2 allocs)
- IPv6 lookups: 3x faster (26.51ns vs 76.96ns, 0 vs 2 allocs)
- Insertions: 20x faster (976ns vs 19,191ns)
- Large tables: 14x faster (5.2ns vs 74.85ns)

* docs: clarify CHANGELOG to not give false impressions

Signed-off-by: Jason Cameron <git@jasoncameron.dev>

* perf: optimize string concatenation in RemoteAddrChecker hash generation

Replace fmt.Fprintln with strings.Join for 7x faster performance:
- Before: 935.1 ns/op, 784 B/op, 22 allocs/op
- After: 133.2 ns/op, 192 B/op, 1 alloc/op

The hash is used for JWT cookie validation and error code generation.
Comma separation provides the same deterministic uniqueness as newlines
but with significantly better performance during policy initialization.

* chore: remove accidentally commited string benchmark

Signed-off-by: Jason Cameron <git@jasoncameron.dev>

* style: apply Copilot suggestions

Signed-off-by: Jason Cameron <git@jasoncameron.dev>

* fix: reference the right var name

i cannot write a merge commit

Signed-off-by: Jason Cameron <git@jasoncameron.dev>

---------

Signed-off-by: Jason Cameron <git@jasoncameron.dev>
Jason Cameron 6 days ago
parent
commit
b2b2679bae

+ 1 - 1
.github/actions/spelling/allow.txt

@@ -2,4 +2,4 @@ github
 https
 ssh
 ubuntu
-workarounds
+workarounds

+ 1 - 1
.github/actions/spelling/excludes.txt

@@ -86,4 +86,4 @@
 ^docs/manifest/.*$
 ^docs/static/\.nojekyll$
 ignore$
-robots.txt
+robots.txt

+ 1 - 1
.github/actions/spelling/patterns.txt

@@ -131,4 +131,4 @@ go install(?:\s+[a-z]+\.[-@\w/.]+)+
 
 # hit-count: 1 file-count: 1
 # microsoft
-\b(?:https?://|)(?:(?:(?:blogs|download\.visualstudio|docs|msdn2?|research)\.|)microsoft|blogs\.msdn)\.co(?:m|\.\w\w)/[-_a-zA-Z0-9()=./%]*
+\b(?:https?://|)(?:(?:(?:blogs|download\.visualstudio|docs|msdn2?|research)\.|)microsoft|blogs\.msdn)\.co(?:m|\.\w\w)/[-_a-zA-Z0-9()=./%]*

+ 2 - 0
docs/docs/CHANGELOG.md

@@ -11,6 +11,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+- Replace cidranger with bart for IP range checking, improving IP matching performance by 3-20x with zero heap 
+  allocations
 - Remove the unused `/test-error` endpoint and update the testing endpoint `/make-challenge` to only be enabled in
   development
 - Add `--xff-strip-private` flag/envvar to toggle skipping X-Forwarded-For private addresses or not

+ 0 - 1
go.mod

@@ -16,7 +16,6 @@ require (
 	github.com/playwright-community/playwright-go v0.5200.0
 	github.com/prometheus/client_golang v1.22.0
 	github.com/sebest/xff v0.0.0-20210106013422-671bd2870b3a
-	github.com/yl2chen/cidranger v1.0.2
 	golang.org/x/net v0.41.0
 	google.golang.org/grpc v1.72.2
 	gopkg.in/yaml.v3 v3.0.1

+ 0 - 2
go.sum

@@ -286,8 +286,6 @@ github.com/xanzy/ssh-agent v0.3.3 h1:+/15pJfg/RsTxqYcX6fHqOXZwwMP+2VyYWJeWM2qQFM
 github.com/xanzy/ssh-agent v0.3.3/go.mod h1:6dzNDKs0J9rVPHPhaGCukekBHKqfl+L3KghI1Bc68Uw=
 github.com/xi2/xz v0.0.0-20171230120015-48954b6210f8 h1:nIPpBwaJSVYIxUFsDv3M8ofmx9yWTog9BfvIu0q41lo=
 github.com/xi2/xz v0.0.0-20171230120015-48954b6210f8/go.mod h1:HUYIGzjTL3rfEspMxjDjgmT5uz5wzYJKVo23qUhYTos=
-github.com/yl2chen/cidranger v1.0.2 h1:lbOWZVCG1tCRX4u24kuM1Tb4nHqWkDxwLdoS+SevawU=
-github.com/yl2chen/cidranger v1.0.2/go.mod h1:9U1yz7WPYDwf0vpNWFaeRh0bjwz5RVgRy/9UEQfHl0g=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 gitlab.com/digitalxero/go-conventional-commit v1.0.7 h1:8/dO6WWG+98PMhlZowt/YjuiKhqhGlOCwlIV8SqqGh8=
 gitlab.com/digitalxero/go-conventional-commit v1.0.7/go.mod h1:05Xc2BFsSyC5tKhK0y+P3bs0AwUtNuTp+mTpbCU/DZ0=

+ 12 - 26
lib/policy/checker.go

@@ -3,14 +3,14 @@ package policy
 import (
 	"errors"
 	"fmt"
-	"net"
 	"net/http"
+	"net/netip"
 	"regexp"
 	"strings"
 
 	"github.com/TecharoHQ/anubis/internal"
 	"github.com/TecharoHQ/anubis/lib/policy/checker"
-	"github.com/yl2chen/cidranger"
+	"github.com/gaissmai/bart"
 )
 
 var (
@@ -32,30 +32,25 @@ func NewStaticHashChecker(hashable string) checker.Impl {
 }
 
 type RemoteAddrChecker struct {
-	ranger cidranger.Ranger
-	hash   string
+	prefixTable *bart.Lite
+	hash        string
 }
 
 func NewRemoteAddrChecker(cidrs []string) (checker.Impl, error) {
-	ranger := cidranger.NewPCTrieRanger()
-	var sb strings.Builder
+	table := new(bart.Lite)
 
 	for _, cidr := range cidrs {
-		_, rng, err := net.ParseCIDR(cidr)
+		prefix, err := netip.ParsePrefix(cidr)
 		if err != nil {
 			return nil, fmt.Errorf("%w: range %s not parsing: %w", ErrMisconfiguration, cidr, err)
 		}
 
-		err = ranger.Insert(cidranger.NewBasicRangerEntry(*rng))
-		if err != nil {
-			return nil, fmt.Errorf("%w: error inserting ip range: %w", ErrMisconfiguration, err)
-		}
-		fmt.Fprintln(&sb, cidr)
+		table.Insert(prefix)
 	}
 
 	return &RemoteAddrChecker{
-		ranger: ranger,
-		hash:   internal.FastHash(sb.String()),
+		prefixTable: table,
+		hash:        internal.FastHash(strings.Join(cidrs, ",")),
 	}, nil
 }
 
@@ -65,21 +60,12 @@ func (rac *RemoteAddrChecker) Check(r *http.Request) (bool, error) {
 		return false, fmt.Errorf("%w: header X-Real-Ip is not set", ErrMisconfiguration)
 	}
 
-	addr := net.ParseIP(host)
-	if addr == nil {
-		return false, fmt.Errorf("%w: %s is not an IP address", ErrMisconfiguration, host)
-	}
-
-	ok, err := rac.ranger.Contains(addr)
+	addr, err := netip.ParseAddr(host)
 	if err != nil {
-		return false, err
+		return false, fmt.Errorf("%w: %s is not an IP address: %w", ErrMisconfiguration, host, err)
 	}
 
-	if ok {
-		return true, nil
-	}
-
-	return false, nil
+	return rac.prefixTable.Contains(addr), nil
 }
 
 func (rac *RemoteAddrChecker) Hash() string {

+ 8 - 1
test/go.mod

@@ -5,13 +5,15 @@ go 1.24.2
 replace github.com/TecharoHQ/anubis => ..
 
 require (
-	github.com/TecharoHQ/anubis v1.18.0
+	github.com/TecharoHQ/anubis v1.19.1
 	github.com/facebookgo/flagenv v0.0.0-20160425205200-fcd59fca7456
 	github.com/google/uuid v1.6.0
 )
 
 require (
+	buf.build/gen/go/bufbuild/protovalidate/protocolbuffers/go v1.36.6-20250425153114-8976f5be98c1.1 // indirect
 	cel.dev/expr v0.24.0 // indirect
+	github.com/TecharoHQ/thoth-proto v0.4.0 // indirect
 	github.com/a-h/templ v0.3.898 // indirect
 	github.com/antlr4-go/antlr/v4 v4.13.1 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
@@ -19,8 +21,12 @@ require (
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/facebookgo/ensure v0.0.0-20200202191622-63f1cf65ac4c // indirect
 	github.com/facebookgo/subset v0.0.0-20200203212716-c811ad88dec4 // indirect
+	github.com/gaissmai/bart v0.20.4 // indirect
 	github.com/golang-jwt/jwt/v5 v5.2.2 // indirect
 	github.com/google/cel-go v0.25.0 // indirect
+	github.com/grpc-ecosystem/go-grpc-middleware/providers/prometheus v1.0.1 // indirect
+	github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.1.0 // indirect
+	github.com/joho/godotenv v1.5.1 // indirect
 	github.com/jsha/minica v1.1.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
@@ -37,6 +43,7 @@ require (
 	golang.org/x/text v0.26.0 // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20250519155744-55703ea1f237 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20250519155744-55703ea1f237 // indirect
+	google.golang.org/grpc v1.72.2 // indirect
 	google.golang.org/protobuf v1.36.6 // indirect
 	k8s.io/apimachinery v0.33.1 // indirect
 	sigs.k8s.io/json v0.0.0-20241014173422-cfa47c3a1cc8 // indirect

+ 35 - 6
test/go.sum

@@ -1,7 +1,10 @@
+buf.build/gen/go/bufbuild/protovalidate/protocolbuffers/go v1.36.6-20250425153114-8976f5be98c1.1 h1:YhMSc48s25kr7kv31Z8vf7sPUIq5YJva9z1mn/hAt0M=
+buf.build/gen/go/bufbuild/protovalidate/protocolbuffers/go v1.36.6-20250425153114-8976f5be98c1.1/go.mod h1:avRlCjnFzl98VPaeCtJ24RrV/wwHFzB8sWXhj26+n/U=
 cel.dev/expr v0.24.0 h1:56OvJKSH3hDGL0ml5uSxZmz3/3Pq4tJ+fb1unVLAFcY=
 cel.dev/expr v0.24.0/go.mod h1:hLPLo1W4QUmuYdA72RBX06QTs6MXw941piREPl3Yfiw=
-github.com/a-h/templ v0.3.865 h1:nYn5EWm9EiXaDgWcMQaKiKvrydqgxDUtT1+4zU2C43A=
-github.com/a-h/templ v0.3.865/go.mod h1:oLBbZVQ6//Q6zpvSMPTuBK0F3qOtBdFBcGRspcT+VNQ=
+github.com/TecharoHQ/thoth-proto v0.4.0 h1:UbkvfgCku0Dm1R6O4ug3HOsJNnE6F3wB8x+Dpw2lzFI=
+github.com/TecharoHQ/thoth-proto v0.4.0/go.mod h1:IcGnZt3iYUZQVEa0Lwk5l4ix0hCeXlWUV1TJMZvbWx0=
+github.com/a-h/templ v0.3.898 h1:g9oxL/dmM6tvwRe2egJS8hBDQTncokbMoOFk1oJMX7s=
 github.com/a-h/templ v0.3.898/go.mod h1:oLBbZVQ6//Q6zpvSMPTuBK0F3qOtBdFBcGRspcT+VNQ=
 github.com/antlr4-go/antlr/v4 v4.13.1 h1:SqQKkuVZ+zWkMMNkjy5FZe5mr5WURWnlpmOuzYWrPrQ=
 github.com/antlr4-go/antlr/v4 v4.13.1/go.mod h1:GKmUxMtwp6ZgGwZSva4eWPC5mS6vUAmOABFgjdkM7Nw=
@@ -22,8 +25,16 @@ github.com/facebookgo/stack v0.0.0-20160209184415-751773369052 h1:JWuenKqqX8nojt
 github.com/facebookgo/stack v0.0.0-20160209184415-751773369052/go.mod h1:UbMTZqLaRiH3MsBH8va0n7s1pQYcu3uTb8G4tygF4Zg=
 github.com/facebookgo/subset v0.0.0-20200203212716-c811ad88dec4 h1:7HZCaLC5+BZpmbhCOZJ293Lz68O7PYrF2EzeiFMwCLk=
 github.com/facebookgo/subset v0.0.0-20200203212716-c811ad88dec4/go.mod h1:5tD+neXqOorC30/tWg0LCSkrqj/AR6gu8yY8/fpw1q0=
+github.com/gaissmai/bart v0.20.4 h1:Ik47r1fy3jRVU+1eYzKSW3ho2UgBVTVnUS8O993584U=
+github.com/gaissmai/bart v0.20.4/go.mod h1:cEed+ge8dalcbpi8wtS9x9m2hn/fNJH5suhdGQOHnYk=
+github.com/go-logr/logr v1.4.2 h1:6pFjapn8bFcIbiKo3XT4j/BhANplGihG6tvd+8rYgrY=
+github.com/go-logr/logr v1.4.2/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
+github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
+github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/golang-jwt/jwt/v5 v5.2.2 h1:Rl4B7itRWVtYIHFrSNd7vhTiz9UpLdi6gZhZ3wEeDy8=
 github.com/golang-jwt/jwt/v5 v5.2.2/go.mod h1:pqrtFR0X4osieyHYxtmOUWsAWrfe1Q5UVIyoH402zdk=
+github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
+github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
 github.com/google/cel-go v0.25.0 h1:jsFw9Fhn+3y2kBbltZR4VEz5xKkcIFRPDnuEzAGv5GY=
 github.com/google/cel-go v0.25.0/go.mod h1:hjEb6r5SuOSlhCHmFoLzu8HGCERvIsDAbxDAyNU/MmI=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
@@ -31,6 +42,12 @@ github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
 github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/grpc-ecosystem/go-grpc-middleware/providers/prometheus v1.0.1 h1:qnpSQwGEnkcRpTqNOIR6bJbR0gAorgP9CSALpRcKoAA=
+github.com/grpc-ecosystem/go-grpc-middleware/providers/prometheus v1.0.1/go.mod h1:lXGCsh6c22WGtjr+qGHj1otzZpV/1kwTMAqkwZsnWRU=
+github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.1.0 h1:pRhl55Yx1eC7BZ1N+BBWwnKaMyD8uC+34TLdndZMAKk=
+github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.1.0/go.mod h1:XKMd7iuf/RGPSMJ/U4HP0zS2Z9Fh8Ps9a+6X26m/tmI=
+github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
+github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
 github.com/jsha/minica v1.1.0 h1:O2ZbzAN75w4RTB+5+HfjIEvY5nxRqDlwj3ZlLVG5JD8=
 github.com/jsha/minica v1.1.0/go.mod h1:dxC3wNmD+gU1ewXo/R8jB2ihB6wNpyXrG8aUk5Iuf/k=
 github.com/klauspost/compress v1.18.0 h1:c/Cqfb0r+Yi+JtIEq73FWXVkRonBlf0CRNYc8Zttxdo=
@@ -70,20 +87,32 @@ github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOf
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/yl2chen/cidranger v1.0.2 h1:lbOWZVCG1tCRX4u24kuM1Tb4nHqWkDxwLdoS+SevawU=
 github.com/yl2chen/cidranger v1.0.2/go.mod h1:9U1yz7WPYDwf0vpNWFaeRh0bjwz5RVgRy/9UEQfHl0g=
+go.opentelemetry.io/auto/sdk v1.1.0 h1:cH53jehLUN6UFLY71z+NDOiNJqDdPRaXzTel0sJySYA=
+go.opentelemetry.io/auto/sdk v1.1.0/go.mod h1:3wSPjt5PWp2RhlCcmmOial7AvC4DQqZb7a7wCow3W8A=
+go.opentelemetry.io/otel v1.34.0 h1:zRLXxLCgL1WyKsPVrgbSdMN4c0FMkDAskSTQP+0hdUY=
+go.opentelemetry.io/otel v1.34.0/go.mod h1:OWFPOQ+h4G8xpyjgqo4SxJYdDQ/qmRH+wivy7zzx9oI=
+go.opentelemetry.io/otel/metric v1.34.0 h1:+eTR3U0MyfWjRDhmFMxe2SsW64QrZ84AOhvqS7Y+PoQ=
+go.opentelemetry.io/otel/metric v1.34.0/go.mod h1:CEDrp0fy2D0MvkXE+dPV7cMi8tWZwX3dmaIhwPOaqHE=
+go.opentelemetry.io/otel/sdk v1.34.0 h1:95zS4k/2GOy069d321O8jWgYsW3MzVV+KuSPKp7Wr1A=
+go.opentelemetry.io/otel/sdk v1.34.0/go.mod h1:0e/pNiaMAqaykJGKbi+tSjWfNNHMTxoC9qANsCzbyxU=
+go.opentelemetry.io/otel/sdk/metric v1.34.0 h1:5CeK9ujjbFVL5c1PhLuStg1wxA7vQv7ce1EK0Gyvahk=
+go.opentelemetry.io/otel/sdk/metric v1.34.0/go.mod h1:jQ/r8Ze28zRKoNRdkjCZxfs6YvBTG1+YIqyFVFYec5w=
+go.opentelemetry.io/otel/trace v1.34.0 h1:+ouXS2V8Rd4hp4580a8q23bg0azF2nI8cqLYnC8mh/k=
+go.opentelemetry.io/otel/trace v1.34.0/go.mod h1:Svm7lSjQD7kG7KJ/MUHPVXSDGz2OX4h0M2jHBhmSfRE=
 golang.org/x/exp v0.0.0-20250506013437-ce4c2cf36ca6 h1:y5zboxd6LQAqYIhHnB48p0ByQ/GnQx2BE33L8BOHQkI=
 golang.org/x/exp v0.0.0-20250506013437-ce4c2cf36ca6/go.mod h1:U6Lno4MTRCDY+Ba7aCcauB9T60gsv5s4ralQzP72ZoQ=
-golang.org/x/net v0.40.0 h1:79Xs7wF06Gbdcg4kdCCIQArK11Z1hr5POQ6+fIYHNuY=
-golang.org/x/net v0.40.0/go.mod h1:y0hY0exeL2Pku80/zKK7tpntoX23cqL3Oa6njdgRtds=
+golang.org/x/net v0.41.0 h1:vBTly1HeNPEn3wtREYfy4GZ/NECgw2Cnl+nK6Nz3uvw=
 golang.org/x/net v0.41.0/go.mod h1:B/K4NNqkfmg07DQYrbwvSluqCJOOXwUjeb/5lOisjbA=
 golang.org/x/sys v0.33.0 h1:q3i8TbbEz+JRD9ywIRlyRAQbM0qF7hu24q3teo2hbuw=
 golang.org/x/sys v0.33.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
-golang.org/x/text v0.25.0 h1:qVyWApTSYLk/drJRO5mDlNYskwQznZmkpV2c8q9zls4=
-golang.org/x/text v0.25.0/go.mod h1:WEdwpYrmk1qmdHvhkSTNPm3app7v4rsT8F2UD6+VHIA=
+golang.org/x/text v0.26.0 h1:P42AVeLghgTYr4+xUnTRKDMqpar+PtX7KWuNQL21L8M=
 golang.org/x/text v0.26.0/go.mod h1:QK15LZJUUQVJxhz7wXgxSy/CJaTFjd0G+YLonydOVQA=
 google.golang.org/genproto/googleapis/api v0.0.0-20250519155744-55703ea1f237 h1:Kog3KlB4xevJlAcbbbzPfRG0+X9fdoGM+UBRKVz6Wr0=
 google.golang.org/genproto/googleapis/api v0.0.0-20250519155744-55703ea1f237/go.mod h1:ezi0AVyMKDWy5xAncvjLWH7UcLBB5n7y2fQ8MzjJcto=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20250519155744-55703ea1f237 h1:cJfm9zPbe1e873mHJzmQ1nwVEeRDU/T1wXDK2kUSU34=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20250519155744-55703ea1f237/go.mod h1:qQ0YXyHHx3XkvlzUtpXDkS29lDSafHMZBAZDc03LQ3A=
+google.golang.org/grpc v1.72.2 h1:TdbGzwb82ty4OusHWepvFWGLgIbNo1/SUynEN0ssqv8=
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 google.golang.org/protobuf v1.36.6 h1:z1NpPI8ku2WgiWnf+t9wTPsn6eP1L7ksHUlkfLvd9xY=
 google.golang.org/protobuf v1.36.6/go.mod h1:jduwjTPXsFjZGTmRluh+L6NjiWu7pchiJ2/5YcXBHnY=
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