Send page views through langx.io, because an ad blocker drops posthog.com

[xuelink]

PostHog's project health page had one warning — no reverse proxy — and it was the honest one: every request went to eu.i.posthog.com, which every ad blocker's list contains, so a visitor running one was never counted.

What changed

• functions/ingest/[[path]].js — a Pages Function that forwards /ingest/* to PostHog's European cloud from Cloudflare's edge. /static/ and /array/ go to the asset host and are held in the edge cache; everything else goes to the API host as it arrived. cookie and authorization are dropped (this site sets no cookie, but Cloudflare's __cf_bm is set on langx.io and would otherwise ride along), and CF-Connecting-IP is passed on as X-Forwarded-For — cookieless counting is a hash of the address, so without it a whole country arrives as one visitor.
• src/lib/analytics.ts — api_host is now https://langx.io/ingest, with ui_host set to https://eu.posthog.com so links and the toolbar still point at PostHog.
• .github/workflows/deploy.yml — wrangler looks for a functions directory in its working directory, not inside the directory it publishes, so the artifact carries build/ and functions/ side by side and the publish step names build/ instead of the root. Wrangler's upload ignore list contains functions, so none of it is served as a static file.
• Cookie policy 3.4 — it said the connection to PostHog was made from your browser directly rather than through us. That is no longer true, so it now says what happens, including that we pass your address on. The route changed; the recipient did not.

Testing

Run against a real workerd with wrangler pages dev:

• GET /ingest/static/array.js → 200, PostHog's 288 KB array.js.
• POST /ingest/i/v0/e/ → {"status":"Ok"} from PostHog.
• Loading the site with the SDK pointed at the local proxy produced POST /ingest/e/ 200 OK on its own — end to end, without help.
• Header handling checked by proxying to an echo server: a forged X-Forwarded-For is replaced by the Cloudflare address, cookie and authorization are gone, and method, body and query string arrive unchanged.
• npm run check, npm run lint and vite build pass; site routes are untouched by the function.

The one thing that cannot be tested off main is the artifact layout in Actions — worth a look at the deploy log on the first run.

🤖 Generated with Claude Code

[xuelink]

Duplicate of #164, which landed on main ~20 minutes before this branch was cut and is already deployed: https://langx.io/relay/static/array.js serves PostHog's array.js and the live bundle is built against /relay. Closing in favour of that one — no need for a second proxy on a different path.