From 7762910c2799e7150ae932d3224ed23d459bb5c6 Mon Sep 17 00:00:00 2001
From: Penelope Yong <penelopeysm@gmail.com>
Date: Thu, 2 Jul 2026 01:35:58 +0100
Subject: [PATCH 1/2] Add docs on gha

---
 docs/src/github_actions.md | 33 ++++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/docs/src/github_actions.md b/docs/src/github_actions.md
index b88ef123d..a820d68c3 100644
--- a/docs/src/github_actions.md
+++ b/docs/src/github_actions.md
@@ -1,6 +1,37 @@
 # GitHub Actions
 
-To set up a formatting check in CI, you can use [the `julia-actions/julia-format` action](https://github.com/julia-actions/julia-format): please see that repository's documentations for instructions on how to set it up.
+To set up a formatting check in CI, here is a barebones action.
+This will just fail if any files are not formatted.
+
+!!! note "Pin the version of JuliaFormatter"
+    It is **strongly** recommended that you pin the version of JuliaFormatter used in your CI workflow.
+
+```yaml
+name: Format
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  format:
+    name: Format
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # 7.0.0
+      - uses: julia-actions/setup-julia@fa02766e078afaaf09b14210362cee14137e6a32 # 3.0.2
+      - uses: julia-actions/cache@a45e8fa8be21c18a06b7177052533149e61e9b38 # 3.1.0
+      - name: Install JuliaFormatter
+        run: |
+          julia -e 'using Pkg; Pkg.Apps.add(name="JuliaFormatter", version=v"2.10.1")'
+      - name: Check formatting
+        run: |
+          ${HOME}/.julia/bin/jlfmt --check --verbose .
+```
+
+If you want an action that makes comments on PRs with suggested formatting changes, you can use [the `julia-actions/julia-format` action](https://github.com/julia-actions/julia-format): please see that repository's documentations for instructions on how to set it up.
 
 Alternatively, if you have JuliaFormatter set up as part of your repository's [pre-commit checks](@ref pre-commit) checks, you can directly use pre-commit's CI tooling:
 

From d874d2d1329377573720b0aeda7e5d9a8ab16eb8 Mon Sep 17 00:00:00 2001
From: Penelope Yong <penelopeysm@gmail.com>
Date: Thu, 2 Jul 2026 02:08:05 +0100
Subject: [PATCH 2/2] Apply suggestion from @penelopeysm

---
 docs/src/github_actions.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/src/github_actions.md b/docs/src/github_actions.md
index a820d68c3..cc82a8042 100644
--- a/docs/src/github_actions.md
+++ b/docs/src/github_actions.md
@@ -25,7 +25,7 @@ jobs:
       - uses: julia-actions/cache@a45e8fa8be21c18a06b7177052533149e61e9b38 # 3.1.0
       - name: Install JuliaFormatter
         run: |
-          julia -e 'using Pkg; Pkg.Apps.add(name="JuliaFormatter", version=v"2.10.1")'
+          julia -e 'using Pkg; Pkg.Registry.add("General"); Pkg.Registry.update(); Pkg.Apps.add(name="JuliaFormatter", version=v"2.10.1")'
       - name: Check formatting
         run: |
           ${HOME}/.julia/bin/jlfmt --check --verbose .