misc: update readme and CI

CI just builds the artifacts

.github/workflows/nix.yaml

@@ -0,0 +1,35 @@
+name: nix-build
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  build-and-push-oci:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Login to Docker Hub
+      uses: docker/login-action@v3
+      with:
+        username: ${{ secrets.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_TOKEN }}
+    - uses: cachix/install-nix-action@v25
+      with:
+        nix_path: nixpkgs=channel:nixos-unstable
+    - uses: DeterminateSystems/magic-nix-cache-action@v2
+    - run: |
+        nix build \
+          -L \
+          -o ./imgTarball \
+          '.#ociImgBase'
+    - run: |
+        nix build \
+          -L \
+          -o ./imgTarball \
+          '.#ociImgIqlQuery'
+    - if: github.ref == 'refs/heads/main'
+      run: |
+        docker load -i ./imgTarball
+        docker push --all-tags probcomp/inferenceql.query

README.md

@@ -1,2 +1,32 @@
-# nix
-Nix flakes, modules, and reused utility code across the InferenceQL ecosystem
+# InferenceQL/nix
+
+This repo holds Nix flake, modules, packages, and reusable utility Nix language code for use across the InferenceQL ecosystem.
+
+## Usage
+
+### Build an artifact
+
+Currently, you can build a package directly like so:
+
+```bash
+nix build github.com:InferenceQL/nix#ociImgBase
+```
+
+### Import utility code
+
+To access the `lib` code exported by this flake, declare this repo as a flake input:
+
+```nix
+{
+  inputs = {
+    nixpkgs.url = ...
+    iqlnix.url = "github"
+  };
+  outputs = inputs@{ nixpkgs, iqlnix , ... }: let
+    # call some function
+    toolbox = iqlnix.lib.basicTools "aarch64-darwin";
+  in {
+    ...
+  };
+};
+```