diff --git a/pkgs/by-name/sw/swiftlint/package.nix b/pkgs/by-name/sw/swiftlint/package.nix
index 6fbbc0347230..2fa751c74cff 100644
--- a/pkgs/by-name/sw/swiftlint/package.nix
+++ b/pkgs/by-name/sw/swiftlint/package.nix
@@ -4,7 +4,6 @@
   fetchurl,
   unzip,
   installShellFiles,
-  nix-update-script,
   versionCheckHook,
   runCommand,
 }:
@@ -55,7 +54,7 @@ stdenvNoCC.mkDerivation (finalAttrs: {
   nativeInstallCheckInputs = [ versionCheckHook ];
 
   passthru = {
-    updateScript = nix-update-script { };
+    updateScript = ./update.sh;
     tests = {
       lint =
         runCommand "swiftlint-test-lint"
diff --git a/pkgs/by-name/sw/swiftlint/update.sh b/pkgs/by-name/sw/swiftlint/update.sh
new file mode 100755
index 000000000000..0839de6e5565
--- /dev/null
+++ b/pkgs/by-name/sw/swiftlint/update.sh
@@ -0,0 +1,44 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p curl jq nix
+
+set -euo pipefail
+
+cd "$(dirname "$0")"
+
+old_version=$(jq -r ".version" sources.json)
+version=$(curl -s ${GITHUB_TOKEN:+-u ":$GITHUB_TOKEN"} \
+  "https://api.github.com/repos/realm/SwiftLint/releases/latest" | jq -r ".tag_name")
+
+if [[ "$old_version" == "$version" ]]; then
+    echo "swiftlint is already up to date at $version"
+    exit 0
+fi
+
+echo "Updating swiftlint from $old_version to $version"
+
+declare -A platforms=(
+    [x86_64-linux]="swiftlint_linux_amd64.zip"
+    [aarch64-linux]="swiftlint_linux_arm64.zip"
+    [x86_64-darwin]="portable_swiftlint.zip"
+    [aarch64-darwin]="portable_swiftlint.zip"
+)
+
+sources_tmp="$(mktemp)"
+jq -n --arg v "$version" '{version: $v, platforms: {}}' > "$sources_tmp"
+
+for platform in "${!platforms[@]}"; do
+    filename="${platforms[$platform]}"
+    url="https://github.com/realm/SwiftLint/releases/download/${version}/${filename}"
+    echo "Fetching hash for $platform ($filename)..."
+    sha256hash="$(nix-prefetch-url --type sha256 "$url")"
+    hash="$(nix hash convert --to sri --hash-algo sha256 "$sha256hash")"
+    jq --arg platform "$platform" \
+       --arg filename "$filename" \
+       --arg hash "$hash" \
+       '.platforms += {($platform): {filename: $filename, hash: $hash}}' \
+       "$sources_tmp" > "${sources_tmp}.tmp" && mv "${sources_tmp}.tmp" "$sources_tmp"
+done
+
+mv "$sources_tmp" sources.json
+
+echo "Updated swiftlint to $version"