diff --git a/flake.nix b/flake.nix
index 43682a12d..9605ec9d7 100644
--- a/flake.nix
+++ b/flake.nix
@@ -33,6 +33,7 @@
           git
           just
           libsecret
+          nodePackages.jscpd
           pkg-config
           protobuf
           rust-analyzer
diff --git a/package.json b/package.json
index 5a5c52948..3f64dc5e7 100644
--- a/package.json
+++ b/package.json
@@ -164,6 +164,7 @@
 		"@vitest/coverage-v8": "^4.1.5",
 		"esbuild": "^0.27.4",
 		"jiti": "^2.6.1",
+		"jscpd": "^4.0.9",
 		"typescript": "^5.4.0",
 		"typescript-language-server": "^5.1.3",
 		"vitest": "^4.1.5"