diff --git a/.woodpecker.yml b/.woodpecker.yml
index 8d2264b..c958ae8 100644
--- a/.woodpecker.yml
+++ b/.woodpecker.yml
@@ -6,3 +6,5 @@ pipeline:
     commands:
       - nix flake check
       - nix build '.#mdbook-toc'
+      - nix build '.#docker'
+
diff --git a/flake.nix b/flake.nix
index 2bd0e62..499dbc3 100644
--- a/flake.nix
+++ b/flake.nix
@@ -12,7 +12,12 @@
         packages = rec {
           docker = pkgs.dockerTools.buildLayeredImage {
             name = "mdbook-plus";
-            contents = mdbook-toc;
+            contents = [
+              (pkgs.buildEnv {
+                name = "mdbook-env";
+                paths = with pkgs; [ busybox mdbook mdbook-toc ];
+              })
+            ];
             config.Cmd = [ "${pkgs.mdbook}/bin/mdbook" ];
           };
           mdbook-toc = pkgs.rustPlatform.buildRustPackage rec {