diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9068c07..c0e5893 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,14 +17,12 @@ jobs:
   ci:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
 
-    - uses: cachix/install-nix-action@v22
-      with:
-        nix_path: nixpkgs=channel:nixos-23.05
+    - uses: cachix/install-nix-action@v24
 
-    # build without systemd support for now, since the closure becomes larger
-    - run: nix-build --arg withSystemd false
+    - run: nix build --no-update-lock-file
+    - run: nix flake check --no-update-lock-file
 
     - name: Prepare artifacts
       run: |
diff --git a/default.nix b/build.nix
similarity index 94%
rename from default.nix
rename to build.nix
index c01cd71..42024e8 100644
--- a/default.nix
+++ b/build.nix
@@ -1,9 +1,7 @@
-{ pkgs ? import <nixpkgs> {}, withSystemd ? true }:
+{ pkgs, ttRss, withSystemd ? true }:
 
 let
 
-  ttRss = (import ./tt-rss.nix { inherit pkgs; });
-
   php = (pkgs.php.override {
     embedSupport = true;
     cliSupport = true;
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..5864714
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1702233072,
+        "narHash": "sha256-H5G2wgbim2Ku6G6w+NSaQaauv6B6DlPhY9fMvArKqRo=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "781e2a9797ecf0f146e81425c822dca69fe4a348",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-23.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..48db773
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,13 @@
+{
+  description = ''Portable "Tiny Tiny Rss" service run by uwsgi-php and built with Nix'';
+
+  inputs.nixpkgs.url = github:NixOS/nixpkgs/nixos-23.11;
+
+  outputs = { self, nixpkgs, ... }:
+    let
+      pkgs = import nixpkgs { system = "x86_64-linux"; };
+      ttRss = (import ./tt-rss.nix { inherit pkgs; });
+    in {
+      packages.x86_64-linux.default = (import ./build.nix { inherit pkgs ttRss; withSystemd = false; });
+    };
+}