From 98f5787c92c8e86478687258637aed20905906a7 Mon Sep 17 00:00:00 2001
From: Michael Pontus <m.pontus@gmail.com>
Date: Thu, 25 Aug 2022 15:34:24 +0300
Subject: [PATCH 1/2] chore(flake): Override toolchain using
 `fenix.fromTemplateFile`

This enables wasm target in Rust toolchain used to build the package.
---
 flake.nix | 24 ++++++++----------------
 1 file changed, 8 insertions(+), 16 deletions(-)

diff --git a/flake.nix b/flake.nix
index b2d5eb67a8..5102ac971b 100644
--- a/flake.nix
+++ b/flake.nix
@@ -23,26 +23,20 @@
           pkgs = inputs.nixpkgs.legacyPackages.${system};
 
           cargoTOML = builtins.fromTOML (builtins.readFile ./Cargo.toml);
-          rustToolChainTOML = builtins.fromTOML (builtins.readFile ./rust-toolchain.toml);
 
           name = cargoTOML.package.name;
           # This is the program version.
           version = cargoTOML.package.version;
-          # This selects a nightly Rust version, based on the date.
-          nightly-date = pkgs.lib.strings.removePrefix "nightly-" rustToolChainTOML.toolchain.channel;
-          # This is the hash of the Rust toolchain at nightly-date, required for reproducibility.
-          nightly-sha256 = "sha256-CNMj0ouNwwJ4zwgc/gAeTYyDYe0botMoaj/BkeDTy4M=";
 
-
-          # This instantiates a new Rust version based on nightly-date.
+          # Override the toolchain from Rust toolchain file
+          fenix = inputs.fenix.packages.${system};
+          toolchain = fenix.fromToolchainFile {
+            file = ./rust-toolchain.toml;
+            sha256 = "sha256-CNMj0ouNwwJ4zwgc/gAeTYyDYe0botMoaj/BkeDTy4M=";
+          };
           nightlyRustPlatform = pkgs.makeRustPlatform {
-            inherit
-              (inputs.fenix.packages.${system}.toolchainOf {
-                channel = "nightly";
-                date = nightly-date;
-                sha256 = nightly-sha256;
-              })
-              cargo rustc;
+            cargo = toolchain;
+            rustc = toolchain;
           };
 
           # This is a mock git program, which just returns the commit-substr value.
@@ -108,8 +102,6 @@
 
             LIBCLANG_PATH = "${pkgs.llvmPackages.libclang.lib}/lib";
             PROTOC = "${pkgs.protobuf}/bin/protoc";
-            SKIP_WASM_BUILD = 1;
-
 
             doCheck = false;
           };

From 7d265eb93f658665187818e6c74d2b0e902ce50a Mon Sep 17 00:00:00 2001
From: Michael Pontus <m.pontus@gmail.com>
Date: Thu, 25 Aug 2022 16:53:36 +0300
Subject: [PATCH 2/2] chore(flake): use naersk to build rust package

---
 flake.lock | 21 +++++++++++++++++++++
 flake.nix  | 12 ++++++++++--
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/flake.lock b/flake.lock
index 02c6bdb3e1..9c3a2ea7c2 100644
--- a/flake.lock
+++ b/flake.lock
@@ -56,6 +56,26 @@
         "type": "github"
       }
     },
+    "naersk": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1659610603,
+        "narHash": "sha256-LYgASYSPYo7O71WfeUOaEUzYfzuXm8c8eavJcel+pfI=",
+        "owner": "nmattia",
+        "repo": "naersk",
+        "rev": "c6a45e4277fa58abd524681466d3450f896dc094",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nmattia",
+        "repo": "naersk",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1658346836,
@@ -77,6 +97,7 @@
         "fenix": "fenix",
         "flake-utils": "flake-utils",
         "gitignore": "gitignore",
+        "naersk": "naersk",
         "nixpkgs": "nixpkgs"
       }
     },
diff --git a/flake.nix b/flake.nix
index 5102ac971b..633ac20211 100644
--- a/flake.nix
+++ b/flake.nix
@@ -15,6 +15,10 @@
       url = github:nix-community/fenix;
       inputs.nixpkgs.follows = "nixpkgs";
     };
+    naersk = {
+      url = github:nmattia/naersk;
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
   outputs = inputs :
@@ -34,7 +38,7 @@
             file = ./rust-toolchain.toml;
             sha256 = "sha256-CNMj0ouNwwJ4zwgc/gAeTYyDYe0botMoaj/BkeDTy4M=";
           };
-          nightlyRustPlatform = pkgs.makeRustPlatform {
+          naersk' = pkgs.callPackage inputs.naersk {
             cargo = toolchain;
             rustc = toolchain;
           };
@@ -77,7 +81,7 @@
               && builtins.all (name: builtins.baseNameOf path != name) ignoreList;
         in
         rec {
-          defaultPackage = nightlyRustPlatform.buildRustPackage {
+          defaultPackage = naersk'.buildPackage {
             pname = name;
             inherit version;
 
@@ -103,6 +107,10 @@
             LIBCLANG_PATH = "${pkgs.llvmPackages.libclang.lib}/lib";
             PROTOC = "${pkgs.protobuf}/bin/protoc";
 
+            # Either this or `singleStep = true` is needed to build.
+            # See https://github.com/nix-community/naersk/issues/133
+            copySources = ["runtime/development"];
+
             doCheck = false;
           };