Build Wasm contract with Nix

.github/workflows/integration.yaml

@@ -279,15 +279,6 @@ jobs:
           toolchain: stable
       - name: Install cargo-nextest
         run: curl -LsSf https://get.nexte.st/latest/linux | tar zxf - -C ${CARGO_HOME:-~/.cargo}/bin
-      - name: Download latest IBC client CosmWasm contract
-        uses: actions/download-artifact@v4
-        with:
-          run-id: ${{ env.UPLOAD_WASM_RUN_ID }}
-          repository: cosmos/ibc-rs
-          pattern: tendermint-cw-*
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-      - name: Relocate CosmWasm contract
-        run: mv tendermint-cw-*/ibc_client_tendermint_cw.wasm tools/integration-test/fixtures/wasm/ibc_client_tendermint_cw.wasm
       - name: Build tests
         uses: actions-rs/cargo@v1
         with:
@@ -301,7 +292,9 @@ jobs:
           CHAIN_COMMAND_PATHS: ${{ matrix.chain.command }}
           ACCOUNT_PREFIXES: ${{ matrix.chain.account_prefix }}
           NATIVE_TOKENS: ${{ matrix.chain.native_token }}
+          IBC_CLIENT_WASM_FILE: ${{ github.workspace }}/result/ibc_client_tendermint_cw.wasm
         run: |
+          nix build .#ibc-client-tendermint-cw
           nix shell .#python ${{ matrix.chain.package }} -c \
             cargo nextest run -p ibc-integration-test --no-fail-fast --failure-output final --test-threads=2 \
             --features wasm wasm_client

flake.nix

@@ -4,6 +4,7 @@
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
     flake-utils.url = "github:numtide/flake-utils";
+    rust-overlay.url = "github:oxalica/rust-overlay";
     cosmos-nix.url = "github:informalsystems/cosmos.nix";
     cosmos-nix-wasm.url = "github:informalsystems/cosmos.nix/jonathan/ibc-go-wasm";
   };
@@ -23,16 +24,26 @@
         let
           nixpkgs = import inputs.nixpkgs {
             inherit system;
+            overlays = [
+              inputs.rust-overlay.overlays.default
+            ];
           };
 
           cosmos-nix = inputs.cosmos-nix.packages.${system};
           cosmos-nix-wasm = inputs.cosmos-nix-wasm.packages.${system};
+
+          ibc-client-tendermint-cw =
+            import ./nix/ibc-client-tendermint-cw.nix
+              {
+                inherit nixpkgs;
+              };
         in
         {
           packages = {
             inherit
               (cosmos-nix)
-              apalache
+              # apalache
+
               celestia
               cometbft
               evmos
@@ -62,6 +73,8 @@
               ibc-go-v7-wasm-simapp
               ;
 
+            ibc-client-tendermint-cw = ibc-client-tendermint-cw;
+
             python = nixpkgs.python3.withPackages (p: [
               p.toml
             ]);

nix/ibc-client-tendermint-cw.nix

@@ -0,0 +1,42 @@
+{ nixpkgs }:
+let
+  rustWithWasmTarget =
+    nixpkgs.rust-bin.stable.latest.default.override
+      {
+        targets = [ "wasm32-unknown-unknown" ];
+      };
+
+  rustWasmPlatform = nixpkgs.makeRustPlatform {
+    cargo = rustWithWasmTarget;
+    rustc = rustWithWasmTarget;
+  };
+in
+rustWasmPlatform.buildRustPackage {
+  name = "ibc-client-tendermint-cw";
+
+  src = nixpkgs.fetchFromGitHub {
+    owner = "cosmos";
+    repo = "ibc-rs";
+    rev = "d0f7cc41c413bdb1e801acaa566f3e7cf06c2c93";
+    hash = "sha256-LBuP+t7M5KL4a5tbGlALq1B0G3UV3Nqvh4r1X/BgGK0=";
+  };
+
+  cargoLock = {
+    lockFile = ./ibc-rs.Cargo.lock;
+  };
+
+  postPatch = ''
+    ln -s ${./ibc-rs.Cargo.lock} Cargo.lock
+  '';
+
+  doCheck = false;
+
+  buildPhase = ''
+    RUSTFLAGS='-C link-arg=-s' cargo build -p ibc-client-tendermint-cw --target wasm32-unknown-unknown --release --lib --locked
+  '';
+
+  installPhase = ''
+    mkdir -p $out
+    cp target/wasm32-unknown-unknown/release/ibc_client_tendermint_cw.wasm $out/
+  '';
+}