diff --git a/go.mod b/go.mod
index 7981059..b9a4707 100644
--- a/go.mod
+++ b/go.mod
@@ -5,6 +5,7 @@ go 1.25.0
 require (
 	codeberg.org/git-pages/go-headers v1.1.1
 	codeberg.org/git-pages/go-slog-syslog v0.0.0-20251207093707-892f654e80b7
+	github.com/BurntSushi/toml v1.6.0
 	github.com/KimMachineGun/automemlimit v0.7.5
 	github.com/bits-and-blooms/bloom/v3 v3.7.1
 	github.com/c2h5oh/datasize v0.0.0-20231215233829-aa82cc1e6500
@@ -18,7 +19,6 @@ require (
 	github.com/klauspost/compress v1.18.5
 	github.com/maypok86/otter/v2 v2.3.0
 	github.com/minio/minio-go/v7 v7.0.100
-	github.com/pelletier/go-toml/v2 v2.3.0
 	github.com/pquerna/cachecontrol v0.2.0
 	github.com/prometheus/client_golang v1.23.2
 	github.com/samber/slog-multi v1.8.0
diff --git a/go.sum b/go.sum
index c7a8858..e9e3ec3 100644
--- a/go.sum
+++ b/go.sum
@@ -2,6 +2,8 @@ codeberg.org/git-pages/go-headers v1.1.1 h1:fpIBELKo66Z2k+gCeYl5mCEXVQ99Lmx1iup1
 codeberg.org/git-pages/go-headers v1.1.1/go.mod h1:N4gwH0U3YPwmuyxqH7xBA8j44fTPX+vOEP7ejJVBPts=
 codeberg.org/git-pages/go-slog-syslog v0.0.0-20251207093707-892f654e80b7 h1:+rkrAxhNZo/eKEcKOqVOsF6ohAPv5amz0JLburOeRjs=
 codeberg.org/git-pages/go-slog-syslog v0.0.0-20251207093707-892f654e80b7/go.mod h1:8NPSXbYcVb71qqNM5cIgn1/uQgMisLbu2dVD1BNxsUw=
+github.com/BurntSushi/toml v1.6.0 h1:dRaEfpa2VI55EwlIW72hMRHdWouJeRF7TPYhI+AUQjk=
+github.com/BurntSushi/toml v1.6.0/go.mod h1:ukJfTF/6rtPPRCnwkur4qwRxa8vTRFBF0uk2lLoLwho=
 github.com/KimMachineGun/automemlimit v0.7.5 h1:RkbaC0MwhjL1ZuBKunGDjE/ggwAX43DwZrJqVwyveTk=
 github.com/KimMachineGun/automemlimit v0.7.5/go.mod h1:QZxpHaGOQoYvFhv/r4u3U0JTC2ZcOwbSr11UZF46UBM=
 github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERoyfY=
@@ -94,8 +96,6 @@ github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 h1:onHthvaw9LFnH4t2DcNVpwGmV9E1BkGknEliJkfwQj0=
 github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58/go.mod h1:DXv8WO4yhMYhSNPKjeNKa5WY9YCIEBRbNzFFPJbWO6Y=
-github.com/pelletier/go-toml/v2 v2.3.0 h1:k59bC/lIZREW0/iVaQR8nDHxVq8OVlIzYCOJf421CaM=
-github.com/pelletier/go-toml/v2 v2.3.0/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/philhofer/fwd v1.2.0 h1:e6DnBTl7vGY+Gz322/ASL4Gyp1FspeMvx1RNDoToZuM=
 github.com/philhofer/fwd v1.2.0/go.mod h1:RqIHx9QI14HlwKwm98g9Re5prTQ6LdeRQn+gXJFxsJM=
 github.com/pjbgf/sha1cd v0.5.0 h1:a+UkboSi1znleCDUNT3M5YxjOnN1fz2FhN48FlwCxs0=
diff --git a/gomod2nix.toml b/gomod2nix.toml
index 97a7d8a..861be76 100644
--- a/gomod2nix.toml
+++ b/gomod2nix.toml
@@ -7,6 +7,9 @@ schema = 3
   [mod."codeberg.org/git-pages/go-slog-syslog"]
     version = "v0.0.0-20251207093707-892f654e80b7"
     hash = "sha256-ye+DBIyxqTEOViYRrQPWyGJCaLmyKSDwH5btlqDPizM="
+  [mod."github.com/BurntSushi/toml"]
+    version = "v1.6.0"
+    hash = "sha256-ptdUJvuc21ixeLt+M5way/na3aCnCO4MYHWulWp8NEY="
   [mod."github.com/KimMachineGun/automemlimit"]
     version = "v0.7.5"
     hash = "sha256-lH/ip9j2hbYUc2W/XIYve/5TScQPZtEZe3hu76CY//k="
@@ -115,9 +118,6 @@ schema = 3
   [mod."github.com/pbnjay/memory"]
     version = "v0.0.0-20210728143218-7b4eea64cf58"
     hash = "sha256-QI+F1oPLOOtwNp8+m45OOoSfYFs3QVjGzE0rFdpF/IA="
-  [mod."github.com/pelletier/go-toml/v2"]
-    version = "v2.3.0"
-    hash = "sha256-3ftKBqSwUp5rs10NigReAJ8RxfnP4Aol45EkP0XRaa4="
   [mod."github.com/philhofer/fwd"]
     version = "v1.2.0"
     hash = "sha256-cGx2/0QQay46MYGZuamFmU0TzNaFyaO+J7Ddzlr/3dI="
diff --git a/renovate.json b/renovate.json
index f06b5df..23aeee6 100644
--- a/renovate.json
+++ b/renovate.json
@@ -8,10 +8,6 @@
     {
       "matchPackageNames": ["actions/buildah-simple"],
       "enabled": false
-    },
-    {
-      "matchPackageNames": ["github.com/pelletier/go-toml/v2"],
-      "enabled": false // added AGENTS.md; v2.3.0 has been manually reviewed
     }
   ],
   "automerge": false,
diff --git a/src/config.go b/src/config.go
index 37b0c75..c88cd89 100644
--- a/src/config.go
+++ b/src/config.go
@@ -12,9 +12,9 @@ import (
 	"strings"
 	"time"
 
+	"github.com/BurntSushi/toml"
 	"github.com/c2h5oh/datasize"
 	"github.com/creasty/defaults"
-	"github.com/pelletier/go-toml/v2"
 )
 
 // For an unknown reason, the standard `time.Duration` type doesn't implement the standard
@@ -309,23 +309,28 @@ func PrintConfigEnvVars() {
 	})
 }
 
+func PrettyTomlKey(key toml.Key) string {
+	if len(key) == 1 {
+		return key.String()
+	} else {
+		// `toml.Key.String()` adds quotes if necessary.
+		return fmt.Sprintf("[%s].%s", key[:len(key)-1].String(), key[len(key)-1:].String())
+	}
+}
+
 func ReadConfigFile(config *Config, tomlPath string) (err error) {
 	if tomlPath != "" {
-		var file *os.File
-		file, err = os.Open(tomlPath)
+		meta, err := toml.DecodeFile(tomlPath, config)
 		if err != nil {
-			return
+			return err
 		}
 
-		defer func(file *os.File) {
-			err = file.Close()
-		}(file)
-
-		decoder := toml.NewDecoder(file)
-		decoder.DisallowUnknownFields()
-		decoder.EnableUnmarshalerInterface()
-		if err = decoder.Decode(&config); err != nil {
-			return
+		unknownKeys := []string{}
+		for _, key := range meta.Undecoded() {
+			unknownKeys = append(unknownKeys, PrettyTomlKey(key))
+		}
+		if len(unknownKeys) > 0 {
+			return fmt.Errorf("unknown keys: %s", strings.Join(unknownKeys, ", "))
 		}
 	}
 	return nil