build from source

flake.nix

@@ -19,7 +19,7 @@
         in
         {
           packages = {
-            open-lens =
+            open-lens-from-binary =
               let
                 pname = "open-lens";
                 version = "6.1.19";
@@ -56,13 +56,21 @@
                     '';
                 };
               };
-
-            apps = {
-              # asdm = {
-              #   type = "app";
-              #   program = "${self.packages.${system}.mpc}/bin/mpc";
-              # };
-            };
+            open-lens-from-source =
+              let
+                version = "6.2.0";
+              in
+              pkgs.mkYarnPackage {
+                src = pkgs.fetchFromGitHub {
+                  owner = "lensapp";
+                  repo = "lens";
+                  rev = "v${version}";
+                  sha256 = "sha256-jJt731hUbBYFHZ9dJDfHPss1loIgyEogWwRQtukIKs8=";
+                };
+                buildPhase = ''
+                  make build
+                '';
+              };
           };
         }
       );

result

@@ -0,0 +1 @@
+/nix/store/y3njclwrx38amm39ccgqzhvakq3hkvm1-open-lens-6.1.19