Hosting

Grid/84 is dual-hosted from one artifact. Every push to main runs the checks, builds dist/ and deploys it to GitHub Pages at https://emmettl.github.io/grid84/ (.github/workflows/pages.yml). The same artifact is deployed to https://grid84.app/ as a Cloudflare Worker with static assets (wrangler.jsonc): the Worker has no script, only the files, and the domain and www are its custom domains, so Cloudflare keeps the DNS records itself. The build uses a relative base (base: './' in vite.config.ts) and hash routes, so the artifact serves at the root of a domain or under a path without change.

The Motion Studies sub-path edition (motionstudies.app/grid84) was retired on 10 September 2026: the atlas has too much of its own identity to be a sub-path of another site. Its grid84 entry in Motion Studies' hosting/editions.json can go when convenient.

Deploying the Worker

From a machine logged in to wrangler (npx wrangler login):

npm run build && npx wrangler deploy

The Pages workflow does the same in its worker job when the repository secret CLOUDFLARE_API_TOKEN exists; without it the job prints a note and grid84.app keeps its last deployment. The token comes from the Cloudflare dashboard, My Profile → API Tokens → Create Token → the Edit Cloudflare Workers template, with Account Resources set to this account and Zone Resources to grid84.app. A wrangler login's OAuth session cannot mint tokens (it lacks the API-tokens scope), so this is a dashboard step. The account id is in wrangler.jsonc; it is not a secret.

Caching

public/_headers is honoured by the Worker and ignored by GitHub Pages, and follows the editions' policy: hashed files under /assets/ are public, max-age=31536000, immutable; the HTML and the grids index are public, max-age=0, must-revalidate; the study grids under /data/hyde/ revalidate daily; /_release.json, which the workflow writes with the commit and run, is no-cache. GitHub Pages applies its own ten-minute policy to everything.

Checks

curl -sI https://grid84.app/ | grep -i -E "server|cache-control|x-grid84"
curl -sI https://grid84.app/assets/$(curl -s https://grid84.app/ | grep -o 'assets/index-[^"]*\.js' | head -1 | cut -d/ -f2) | grep -i cache-control
curl -s https://grid84.app/_release.json
curl -sI https://emmettl.github.io/grid84/ | grep -i -E "server|cache-control"

The grids

Both hosts read the GHSL grids from the R2 bucket grid84-grids, named in public/data/hyde/index.json as https://tiles.grid84.app/ghsl/…: a custom domain on the bucket (wrangler r2 bucket domain add grid84-grids --domain tiles.grid84.app --zone-id …), for which Cloudflare keeps the DNS record. The bucket's r2.dev URL still answers and the CORS rule (GET and HEAD from any origin, Range allowed) applies to both. The grid files are immutable by name (popc_1985.json and its tiles), so a Cache Rule on the zone for tiles.grid84.app/* with a long edge TTL is worth adding in the dashboard; the bucket domain itself sets none.