Some progress towards enabling wasmd on macOS

Author: zah

packages/wasmd/default.nix

@@ -5,6 +5,11 @@
   buildGoModule,
   autoPatchelfHook,
 }:
+let
+  wasmvmLib = if stdenv.isLinux then "libwasmvm.x86_64.so"
+              else if stdenv.isDarwin then "libwasmvm.dylib"
+              else throw "platform not supported";
+in
 buildGoModule rec {
   pname = "wasmd";
   version = "0.14.99";
@@ -19,21 +24,33 @@ buildGoModule rec {
 
   subPackages = ["cmd/wasmd"];
 
-  buildInputs = [autoPatchelfHook];
+  buildInputs = [] ++ lib.optional stdenv.isLinux [autoPatchelfHook];
 
   postBuild = ''
     mkdir -p "$out/lib"
     # TODO: The correct binary below should depend on the current OS and CPU
-    cp "$GOPATH/pkg/mod/github.com/!cosm!wasm/[email protected]/api/libwasmvm.x86_64.so" "$out/lib"
+    cp "$GOPATH/pkg/mod/github.com/!cosm!wasm/[email protected]/api/${wasmvmLib}" "$out/lib"
   '';
 
-  postInstall = ''
+  postInstall = if stdenv.isLinux then ''
     addAutoPatchelfSearchPath "$out/lib"
     # TODO: autoPatchElf is Linux-specific. We need a cross-platform solution
     autoPatchelf -- "$out/bin"
-  '';
+  '' else
+  # TODO
+  # The package is still not working because we are missing the equivalent
+  # of autopatchelf for macOS. The "libwasmvm.dylib" is currently distributed
+  # as a pre-built binary by the wasmd team (it's stored in git). This leads
+  # to the final wasmd binary having a `rpath` which cannot be satisfied at
+  # run-time with Nix.
+  "";
+
+  vendorSha256 = if stdenv.isLinux then
+    "sha256-4vW1+vGOwbaE6fVXtHjKMheX9UpiY7WVh7QCC57QQUM="
+  else if stdenv.isDarwin then
+    "sha256-vACKDwUP52iSjb0DC+dIuNrOeBMLnKBDYsNpQrq3IqI="
+  else "";
 
-  vendorSha256 = "sha256-4vW1+vGOwbaE6fVXtHjKMheX9UpiY7WVh7QCC57QQUM=";
   doCheck = false;
   meta = with lib; {
     description = "Basic cosmos-sdk app with web assembly smart contracts";

shell.nix

@@ -12,12 +12,12 @@ with pkgs;
         # Packages defined in this repo
         metacraft-labs.cosmos-theta-testnet
         metacraft-labs.circom
+        metacraft-labs.wasmd
         metacraft-labs.circ
       ]
       ++ lib.optionals (!stdenv.isDarwin) [
         # Solana is still not compatible with macOS on M1
         metacraft-labs.solana
-        metacraft-labs.wasmd
       ];
 
     shellHook = ''