diff --git a/flake.nix b/flake.nix
index 88818fa..d3a98be 100644
--- a/flake.nix
+++ b/flake.nix
@@ -56,13 +56,18 @@
 			};
 		};
 
-		nixosTests.nwc-wallets-port-collision =
-			import ./nix/tests/nwc-wallets-port-collision.nix {
-				inherit nixpkgs;
+		checks.x86_64-linux = let
+			pkgs = import nixpkgs {
 				system = "x86_64-linux";
 			};
-
-		checks.x86_64-linux.nwc-wallets-port-collision =
-			self.nixosTests.nwc-wallets-port-collision;
+			fetchNodeModules =
+				pkgs.callPackage ./packages/build-support/fetch-node-modules.nix {};
+			mempoolPkgs =
+				pkgs.callPackage ./packages/mempool { inherit fetchNodeModules; };
+		in {
+			mempool-backend = mempoolPkgs.mempool-backend;
+			mempool-frontend = mempoolPkgs.mempool-frontend;
+			rtl = pkgs.callPackage ./packages/rtl { inherit fetchNodeModules; };
+		};
 	};
 }
diff --git a/packages/build-support/fetch-node-modules.nix b/packages/build-support/fetch-node-modules.nix
index 2376b6f..80eee78 100644
--- a/packages/build-support/fetch-node-modules.nix
+++ b/packages/build-support/fetch-node-modules.nix
@@ -1,3 +1,5 @@
+# Vendored from fort-nix/nix-bitcoin commit 360e30fee.
+# This local copy does not fetch or import nix-bitcoin.
 # This is a modified version of
 # https://github.com/NixOS/nixpkgs/pull/128749
 
diff --git a/packages/mempool/default.nix b/packages/mempool/default.nix
index bf7cc83..b9df6a1 100644
--- a/packages/mempool/default.nix
+++ b/packages/mempool/default.nix
@@ -1,3 +1,5 @@
+# Packaging adapted from fort-nix/nix-bitcoin commit 360e30fee.
+# This local copy does not fetch or import nix-bitcoin.
 { lib
 , stdenvNoCC
 , nodejs_22
diff --git a/packages/rtl/default.nix b/packages/rtl/default.nix
index 5fd009d..b4f8042 100644
--- a/packages/rtl/default.nix
+++ b/packages/rtl/default.nix
@@ -1,9 +1,10 @@
+# Packaging adapted from fort-nix/nix-bitcoin commit 360e30fee.
+# This local copy does not fetch or import nix-bitcoin.
 { lib
 , stdenvNoCC
 , nodejs_22
 , nodejs-slim_22
 , fetchNodeModules
-, fetchpatch
 , fetchurl
 , makeWrapper
 }: