Vintage letters and postcards with stamps on teal envelope - representing stories of connection

TEEI BLOG

Blog posts, page 4

News and perspectives from TEEI's programmes.

Field reports from corporate volunteering programmes, mentorship cohorts in Ukraine, and the measurable outcomes that prove this model works.

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Diagram: one nonce made for each response, handed to ServerRouter and to renderToReadableStream

TEEI Updates

One Nonce, Two Inputs: Fixing React Router Streaming

We restored loader data with one nonce input. For late Suspense content, we needed the same nonce in another place.

TEEI Team

Sequence diagram of where a React Router error is caught on a Worker, across the browser, the Worker fetch handler, React Router, the error hooks and Sentry

TEEI Updates

How We Join React Router Errors Across Browser and Worker

We can capture an error and still struggle to follow the failure. We compare a shared trace with a request ID across browser and Worker.

TEEI Team

Sequence diagram of a chat message arriving in another tab: a typed ping loads two small resources and leaves the page loaders alone

TEEI Updates

Typed Pings and Failure as Data in React Router

We refresh one unread count without rerunning the page's loaders. To keep the page after a rejected background panel load, we return failure as data.

TEEI Team

Sequence diagram of two requests to the same path on one Worker: a WebSocket upgrade answered before Astro, and an ordinary request handed to Astro

TEEI Updates

Why We Still Handle WebSockets Before Astro

We keep WebSocket upgrades outside Astro as a precaution. Locally, a copied response kept its socket; a rebuild without the socket broke the upgrade.

TEEI Team

Diagram of one React Router route file in the browser build, with the server-only exports removed and the imports that break the build

TEEI Updates

Why We Broke a React Router Build With an Unused Export

We can fail a React Router build on code we would never send to the browser: we check imports before we drop unused code. How we split our files.

TEEI Team

One page request: a single long hop from the person to a data centre near the database, where the Worker runs and makes short trips to the database

TEEI Updates

Cloudflare Workers: Shorter Trips, Fewer Trips

We run Workers near our database to shorten trips, and batch reads and rewrite loaders to remove them: 84 trips to six on a development server.

TEEI Team

Diagram of the arithmetic from 6,059 pages without a locale prefix to 12,118 redirect pages across two locales

TEEI Updates

We Pruned 12,115 Astro Redirect Pages from Our Build

Pruning Astro fallback pages reduced the files we shipped. Redirecting their old URLs needed a separate fix before the Worker.

TEEI Team

Decision tree of who answers a request on Cloudflare, the Worker or a built asset, by the run_worker_first setting and the compatibility date

TEEI Updates

Worker First Is Not Middleware First: Astro on Cloudflare

In our Astro setup, we got 404s for old image URLs. We trace why we needed redirects before the adapter, even with Worker first.

TEEI Team

Diagram of three ways one Worker reaches another: a public fetch, a fetch binding and an RPC binding

TEEI Updates

What We Bypass with Cloudflare Service Bindings

We moved a failing call onto a service binding and it kept failing. Weeks later we found that our RPC calls could write through a maintenance pause.

TEEI Team

Diagram of where the Worker binding limit is checked: by Cloudflare at the secret write without a count, by our own count before the write with one

TEEI Updates

Counting to 128 Before We Add One Worker Secret

We count built variables before a deploy and deployed variables before a secret write, adding the live secret inventory in both cases.

TEEI Team

Diagram of the TEEI programmes on one Amazon Chime SDK layer, with meeting events flowing on to programme history and, nightly, to Evenhall

TEEI Updates

What TEEI Runs on AWS

The AWS services that carry TEEI's free programmes, measured: Chime video, Bedrock checks and who decides, monitoring, and how releases are verified.

TEEI Team

TEEI Updates

How TEEI Turns Amazon Chime SDK Events into Verified Hours

TEEI's free programmes run on Amazon Chime SDK, and every verified volunteer hour, up to the company report in Evenhall, starts as a meeting event.

TEEI Team

Blog posts, page 4

Blog posts, page 4

One Nonce, Two Inputs: Fixing React Router Streaming

How We Join React Router Errors Across Browser and Worker

Typed Pings and Failure as Data in React Router

Why We Still Handle WebSockets Before Astro

Why We Broke a React Router Build With an Unused Export

Cloudflare Workers: Shorter Trips, Fewer Trips

We Pruned 12,115 Astro Redirect Pages from Our Build

Worker First Is Not Middleware First: Astro on Cloudflare

What We Bypass with Cloudflare Service Bindings

Counting to 128 Before We Add One Worker Secret

What TEEI Runs on AWS

How TEEI Turns Amazon Chime SDK Events into Verified Hours

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