pkgs: add woodpecker

This is just the same version as upstream, but following the `next`
version.

pkgs/woodpecker/common.nix

@@ -0,0 +1,38 @@
+{ lib, fetchFromGitHub }:
+let
+  rev = "e7ca28026bc4576b2dd30aa2ab71c2d07dfc7197";
+  srcHash = "sha256-vtttb+tRi3uDFn8liFgZcAqWLENfpTY7lWsNCoTFzEM=";
+  vendorHash = "sha256-u7HT8+LeqS7mCNbUhrvSW0xd/uduL2Kw7A0mUUpW2w4=";
+  yarnHash = "sha256-h+he2VxvZlStIoLb1PPxqKSmTfFNGgJmUXptjtc5xD8=";
+  version = "next-${lib.substring 0 8 rev}";
+in
+{
+  inherit version yarnHash vendorHash;
+
+  src = fetchFromGitHub {
+    owner = "woodpecker-ci";
+    repo = "woodpecker";
+    inherit rev;
+    hash = srcHash;
+  };
+
+  postInstall = ''
+    cd $out/bin
+    for f in *; do
+      mv -- "$f" "woodpecker-$f"
+    done
+    cd -
+  '';
+
+  ldflags = [
+    "-s"
+    "-w"
+    "-X github.com/woodpecker-ci/woodpecker/version.Version=${version}"
+  ];
+
+  meta = with lib; {
+    homepage = "https://woodpecker-ci.org/";
+    license = licenses.asl20;
+    maintainers = with maintainers; [ ambroisie techknowlogick ];
+  };
+}