diff --git a/pkgs/by-name/la/lamb/package.nix b/pkgs/by-name/la/lamb/package.nix
new file mode 100644
index 000000000000..2da378a2dd7c
--- /dev/null
+++ b/pkgs/by-name/la/lamb/package.nix
@@ -0,0 +1,75 @@
+{
+  lib,
+  stdenv,
+  fetchFromGitHub,
+  gnugrep,
+  nix-update-script,
+}:
+
+stdenv.mkDerivation (finalAttrs: {
+  pname = "lamb";
+  version = "unstable-2025-12-22";
+
+  src = fetchFromGitHub {
+    owner = "tsoding";
+    repo = "lamb";
+    rev = "50938686d4b8ae929121b62a67243baf72867cde";
+    hash = "sha256-ALqjh4DmvysdcGQQrCW87r5rvmCrEWPcViN4zg026nY=";
+  };
+
+  strictDeps = true;
+
+  passthru.updateScript = nix-update-script { extraArgs = [ "--version=unstable" ]; };
+
+  buildPhase = ''
+    runHook preBuild
+    ${stdenv.cc.targetPrefix}cc -o lamb lamb.c
+    runHook postBuild
+  '';
+
+  installPhase = ''
+    runHook preInstall
+
+    install -Dm755 lamb -t "$out/bin"
+    install -Dm644 std.lamb -t "$out/share/lamb"
+
+    runHook postInstall
+  '';
+
+  doCheck = stdenv.buildPlatform.canExecute stdenv.hostPlatform;
+
+  nativeCheckInputs = [
+    gnugrep
+  ];
+
+  checkPhase = ''
+    runHook preCheck
+
+    output="$(
+      {
+        printf '%s\n' \
+          'pair 69 (pair 420 1337)' \
+          'xs = pair 69 (pair 420 1337)' \
+          'first xs' \
+          'second xs' \
+          'first (second xs)' \
+          ':q'
+      } | ./lamb ./std.lamb 2>&1
+    )"
+
+    grep -Fq "RESULT: 69" <<<"$output"
+    grep -Fq "RESULT: 420" <<<"$output"
+
+    runHook postCheck
+  '';
+
+  meta = {
+    description = "Tiny pure functional programming language in C";
+    homepage = "https://github.com/tsoding/lamb";
+    license = lib.licenses.mit;
+    sourceProvenance = with lib.sourceTypes; [ fromSource ];
+    maintainers = with lib.maintainers; [ Zaczero ];
+    mainProgram = "lamb";
+    platforms = lib.platforms.unix;
+  };
+})