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

TEEI BLOG

Blog posts, page 3

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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Matrix of nine TEEI programmes and workspaces against the eight shared building blocks they use: matching, live rooms, classes, practice, feedback, booking, measurement and reporting

TEEI Updates

How TEEI Works: One Platform, Many Programmes

How TEEI works: one platform of shared blocks. A new programme starts on parts that already work, and each is there because research shows what it does.

TEEI Team

Flow diagram of one blog folder feeding one content collection and the seven surfaces built from it

TEEI Updates

Keeping Astro Content, Sitemaps and Search in Sync

We can read from one Astro collection and still disagree on what is published. For a built search index, we filter preview drafts out again.

TEEI Team

Sequence diagram of an old tab meeting a new Worker release: the release header, the comparison in the old document and one guarded reload

TEEI Updates

Old Tabs, New Workers: A Guarded Reload

We traced a crash to old code reading new loader data, then found our tests expecting a failure report from a reload that worked.

TEEI Team

Diagram comparing two reads of a private value from .env: import.meta.env puts the value in the Worker bundle; cloudflare:workers keeps a runtime reference. Our deploy check rejects a bundle when it finds a secret.

TEEI Updates

Astro on Workers: the bugs between build and runtime

We found a 500 before a cache hit, private values in the Worker bundle and missing sitemap routes. Each exposed a boundary we had to migrate.

TEEI Team

Diagram of one request passing zone redirect rules, the Worker entry and static assets on our website

TEEI Updates

Pages to Workers: The Defaults We Had to Rebuild

We moved three apps from Pages to Workers, then changed Cloudflare accounts. We had to rebuild defaults for headers, redirects and deployment targets.

TEEI Team

Architecture diagram of one React Router 8 source tree built twice, into one Cloudflare Worker per programme

TEEI Updates

Two Workers, One React Router 8 App: Decide at the Boundary

We build two Workers from one React Router app, pass programme identity through typed context, and use stored rows for scheduled work.

TEEI Team

Two side-by-side diagrams of one server request under the portal shell: before, three loaders each look the session up in the database; after, middleware looks it up once and the loaders read it from context

TEEI Updates

How We Share One Session Lookup Across React Router Loaders

We found a session lookup in the language helper, outside our list of guards. We moved resolution into layout middleware and gave the context three states.

TEEI Team

Diagram of one activity line: initial HTML, a deferred fragment carrying its view and client, then later socket events

TEEI Updates

Building a Live Homepage with Astro and Cloudflare Workers

A local browser experiment found two ordering bugs in our activity line. We follow the handoffs between Astro, Workers and the visible text.

TEEI Team

Diagram of a completed session becoming a public event without identities. With 20 or more active participants in each country, the sample pair shows as Norway to Ukraine; with fewer than 20 in either, only the regions remain, Northern Europe to Eastern Europe.

TEEI Updates

We Mask Country Pairs Before Storing Live Events

We omit names, coarsen times and mask country pairs before storage, then derive every public view from that record and remove its id at runtime.

TEEI Team

Two sequence diagrams of a learner page reloading after a volunteer answers, before and after 8 September 2026, across the room, the ring status route, the booking database and the Durable Object

TEEI Updates

Durable Objects for Rings, SQL for Outcomes

We had recorded the volunteer's answer, but still removed the learner from the lesson. Here is where live signals end and durable outcomes begin.

TEEI Team

One email in Evenhall: the change and an outbox row are written in one database transaction, the outbox reference and metadata go through a Cloudflare Queue, and we send to Resend under one idempotency key.

TEEI Updates

Why We Freeze Email Payloads on Cloudflare Queues

We could reuse an idempotency key and still change the payload after a deploy. We now store the first attempt’s message fields so a retry can reuse them.

TEEI Team