Add devshell/package caching

.github/workflows/ci.yml

@@ -0,0 +1,80 @@
+name: CI
+
+# Trigger the workflow on all pushes
+on:
+  push:
+    branches:
+      - main
+
+concurrency:
+  group: ${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  packages:
+    name: Push package to local cache
+    runs-on: self-hosted
+    strategy:
+      matrix:
+        ghc-version: [ "ghc9101", "ghc982", "ghc964" ]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build & test
+        run: |
+          # The -L flag outputs build logs to stderr
+          nix build -L .#${{ matrix.ghc-version }}
+
+      - name: Push package to cache
+        env:
+          ATTIC_TOKEN: ${{ secrets.ATTIC_SECRET }}
+        run: |
+          attic login --set-default public http://192.168.102.136:9200/ "$ATTIC_TOKEN"
+          attic push public $(nix path-info .#${{ matrix.ghc-version }})
+
+      - name: Push package to cachix
+        # if: github.ref == 'refs/heads/main'
+        env:
+          CACHIX_TOKEN: ${{ secrets.CACHIX_SECRET }}
+        run: |
+          cachix authtoken $CACHIX_TOKEN
+          nix path-info .#${{ matrix.ghc-version }} | cachix push clash-lang
+
+  devshells:
+    name: Push Nix developer shell to local cache
+    runs-on: self-hosted
+    strategy:
+      matrix:
+        ghc-version: [ "ghc9101", "ghc982", "ghc964" ]
+    steps:
+        # There's no need to configure Nix, the dockerfile handling the GHA has it done for us!
+        # If a dependencies are already cached, we can simply re-use them!
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build devshell
+        run: |
+          # Since the server is x86_64-linux, we can only build the devshell
+          # for that
+          nix build .#devShells.x86_64-linux.${{ matrix.ghc-version }}-full
+
+        # Pushes the binaries to the local network
+        # url: http://192.168.102.136:9200/public
+        # public key: public:PGGlJMx1gGmU069blMqve8tS1ndzBuriUAwGBHGOo4g=
+      - name: Push devshell to cache
+        env:
+          ATTIC_TOKEN: ${{ secrets.ATTIC_SECRET }}
+        run: |
+          attic login --set-default public http://192.168.102.136:9200/ "$ATTIC_TOKEN"
+          attic push public $(nix path-info .#devShells.x86_64-linux.${{ matrix.ghc-version }}-full)
+
+        # Pushes the binaries to Cachix
+      - name: Push devshell to cachix
+        env:
+          CACHIX_TOKEN: ${{ secrets.CACHIX_SECRET }}
+        run: |
+          cachix authtoken $CACHIX_TOKEN
+          nix path-info .#devShells.x86_64-linux.${{ matrix.ghc-version }}-full | cachix push clash-lang
+

README.md

@@ -23,8 +23,37 @@ You can also look through Adam Walker's excellent list of [prebuilt Clash circui
 # Nix
 This project exposes several Nix flake outputs. Most notably the `clash-cores` package, exposed individually or as an overlay (which you need to apply on top of clash-compiler).
 
+## Usage
+
 Contributing to `clash-cores` can be done via the developer shell exposed by the Nix flake. Open a terminal and type: `nix develop`. Optionally a specific GHC version can be selected as well as a `-minimal` or `-full` version. The `-minimal` shell does **NOT** contain the Haskell Language Server, whilst the `-full` shell does. When using the developer shell, do not forget to remove the `cabal.project` file. This file contains a package source and Cabal prioritizes local package sources over Nix sources. Removing the `cabal.project` file should work fine when developing with Nix.
 
+Compiling Clash and all dependencies related to it may take a long time. To remidy long compilation times, you can make use of the publically available cache on Cachix:
+
+### Cachix (binary cache)
+
+Cachix contains all commits on the main branch of `clash-cores` since the cache has been setup. It is recommended to add the publically available cachix cache to your project/computer to minimize the amount of time manually compiling Clash related dependencies.
+
+You can either add user-wide on your local system via `nix.conf` (usually located under `~/.config/nix`, create it if it does not exist):
+```conf
+extra-substituters = https://clash-lang.cachix.org
+extra-trusted-public-keys = clash-lang.cachix.org-1:/2N1uka38B/heaOAC+Ztd/EWLmF0RLfizWgC5tamCBg=
+```
+
+Or as part of your `flake.nix` in your local project:
+```nix
+{
+  nixConfig = {
+    extra-substituters = [ "https://clash-lang.cachix.org" ];
+    extra-trusted-public-keys = [ "clash-lang.cachix.org-1:/2N1uka38B/heaOAC+Ztd/EWLmF0RLfizWgC5tamCBg=" ];
+  };
+  description = ...;
+  inputs = ...;
+  outputs = ...;
+}
+```
+
+## As a dependency
+
 You can also add this project as a Nix-dependency. This project depends on `clash-compiler`, the recommended way to add this to your project as a Nix dependency is as follows:
 
 First add `clash-compiler` and `clash-cores` to your flake inputs: