Publish a preview of every package on every push

.github/workflows/continuous-releases.yml

@@ -0,0 +1,44 @@
+# Every commit pushed to a branch of this repo gets an installable preview of
+# every package, without publishing anything to npm:
+#
+#     npm i https://pkg.pr.new/datocms-structured-text-utils@<commit-sha>
+#
+# The point is to cross a repo boundary while developing. A change here can be
+# tried inside a consumer that lives in another repository — `cms`, a demo, a
+# customer project — from a real tarball, instead of `npm link` or pinning a
+# git branch by hand and remembering to unpin it later. Installing one preview
+# pulls in the previews of its siblings from the same commit, so a change that
+# spans several packages is tried as one coherent set.
+#
+# Pull requests opened from forks are deliberately not published: this runs on
+# pushes to branches of *this* repo, which only people with write access can
+# make, so an unreviewed fork cannot mint a URL under our namespace. If we ever
+# want fork previews too, pkg.pr.new documents an "approved pull requests only"
+# recipe that gates them behind a maintainer's review.
+name: Continuous releases
+
+on:
+  push:
+    # Every branch. Defining `branches` on its own also means tag pushes don't
+    # trigger this, which is what we want: a tag points at a commit that was
+    # already published when it landed on its branch.
+    branches: ['**']
+
+permissions: {}
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version-file: .nvmrc
+          cache: 'npm'
+      - run: npm ci
+      - run: npm run build
+      # Once for all the packages, not once per package: pkg.pr.new expects a
+      # single invocation per workflow run, and rejects the rest as spam.
+      - run: npm exec -- pkg-pr-new publish --commentWithSha './packages/*'

README.md

@@ -70,6 +70,23 @@ requirement; it is the release tooling that does.
 The packages resolve each other through their built `dist/`, so **run
 `npm run build` before `npm test`** on a fresh checkout.
 
+### Trying a change before it's released
+
+Every push to a branch here publishes a preview of all ten packages, which you
+can install anywhere — no npm release, no `npm link`:
+
+```
+npm i https://pkg.pr.new/datocms-structured-text-utils@<commit-sha>
+```
+
+The exact URLs show up in the commit's check run on GitHub, and in a comment on
+the pull request once there is one. Installing one preview pulls in the previews
+of its siblings built from the same commit, so a change spanning several
+packages can be tried as one coherent set.
+
+Previews are throwaway: they are never published to npm, and the URL stops
+resolving after a while. Never commit one to a `package.json` that ships.
+
 ### Releasing (maintainers)
 
 Every user-visible change needs a changeset: run `npx changeset` from the repo

package.json

@@ -15,6 +15,7 @@
     "eslint-config-prettier": "^9.1.0",
     "husky": "^5.2.0",
     "jest": "^29.7.0",
+    "pkg-pr-new": "^0.0.88",
     "prettier": "^2.2.1",
     "pretty-quick": "^3.1.0",
     "rimraf": "^5.0.0",