diff --git a/maintainers/maintainer-list.nix b/maintainers/maintainer-list.nix
index 720c5ea5a1ea..ac3341e5c508 100644
--- a/maintainers/maintainer-list.nix
+++ b/maintainers/maintainer-list.nix
@@ -4389,6 +4389,12 @@
     github = "ciferkey";
     githubId = 101422;
   };
+  ciflire = {
+    name = "Léo Vesse";
+    email = "leovesse@gmail.com";
+    github = "Ciflire";
+    githubId = 39668077;
+  };
   cig0 = {
     name = "Martín Cigorraga";
     email = "cig0.github@gmail.com";
diff --git a/pkgs/by-name/tl/tlafmt/package.nix b/pkgs/by-name/tl/tlafmt/package.nix
new file mode 100644
index 000000000000..f7d5ee71a8b1
--- /dev/null
+++ b/pkgs/by-name/tl/tlafmt/package.nix
@@ -0,0 +1,28 @@
+{
+  rustPlatform,
+  lib,
+  fetchFromGitHub,
+}:
+rustPlatform.buildRustPackage rec {
+  pname = "tlafmt";
+  version = "0.3.0";
+
+  src = fetchFromGitHub {
+    owner = "domodwyer";
+    repo = "tlafmt";
+    tag = "v${version}";
+    hash = "sha256-jBY7erB2LuKwCkshVHLV5kFVRJ8lkT63z1gt1Tikei4=";
+  };
+
+  useFetchCargoVendor = true;
+
+  cargoHash = "sha256-765tp4wUh7G92vaoViufo6Kk2c/w2d1XjZ3aN5UUAv0=";
+
+  meta = {
+    description = "Formatter for TLA+ specs";
+    homepage = "https://github.com/domodwyer/tlafmt";
+    license = lib.licenses.asl20;
+    maintainers = with lib.maintainers; [ ciflire ];
+    mainProgram = "tlafmt";
+  };
+}