Postio is the UK validation API for addresses,
emails and phone numbers. This repo holds the JS-family npm packages,
the AI / agent surface, and the cdn.postio.co.uk Worker that powers
Postio's browser drop-in.
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The Postio API + OpenAPI spec live in
postio-uk/postio-api. The
spec is also published as
@postio/openapi.
| Package | What it is |
|---|---|
@postio/api-types |
TypeScript types generated from the OpenAPI spec. |
@postio/core |
Runtime-agnostic typed client (browser / Node / Workers / Bun / Deno). |
@postio/node |
Node SDK on top of core — retries with exponential backoff, structured logger hook. |
@postio/postman-collection |
Postman v2.1 collection for every endpoint. |
@postio/address-finder |
Browser address autocomplete — ARIA combobox, themable, framework-agnostic source. |
@postio/address-finder-bundled |
The same component prebuilt for <script> tag use. |
@postio/react |
React hooks + <AddressFinder /> component, TanStack Query under the hood. |
@postio/mcp |
Model Context Protocol server — npx -y @postio/mcp for Claude Desktop / Cursor / Windsurf / Zed. |
packages/ pnpm workspace; one publishable npm package per subdir
ai/ AI / agent surface (Claude Skill, GPT Action, recommendation prompts)
cdn-worker/ Cloudflare Worker that serves the address-finder bundles
.github/workflows/ CI for publishing + deploying
cd packages
pnpm install
pnpm -r run buildEach package builds independently (pnpm -F @postio/<name> run build).
The address-finder bundle has a topological-build quirk — use the
... suffix so its workspace dep builds first:
pnpm -F "@postio/address-finder-bundled..." run buildPRs welcome. Conventions:
- Node 22+, pnpm 10+, ESM only, MIT-licensed.
stageis the working branch;masterdeploys / publishes via CI.- One package change per PR where possible.
- Versions on each package are independent SemVer; bump the version
in
package.jsonwhen you intend a release.
The full integration index — including the server SDKs in their own repos and the WordPress plugin — lives at postio.co.uk/integrations.
MIT.