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INTEGRATIONS

Every way to call Postio.

A typed client for whatever you're building in. Drop a script tag, npm install, wire up a coding agent, or hand a plugin to a marketing team. Pick the surface that fits your stack.

Browser SDK

Drop a script tag, get a UK address autocomplete in the browser.
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Address FinderActive

Drop-in UK address autocomplete. ARIA-compliant combobox, keyboard nav, themable via CSS custom properties. ~4 KB gzipped.

<script src="https://cdn.postio.co.uk/v1/address-finder.js"></script>Read the install guide

Server SDKs

Official, hand-tested clients for every popular backend language.
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Node.jsActive

Node-flavoured server SDK on top of @postio/core. Retries with exp backoff + full jitter, structured logger hook, 30s default timeout.

npm i @postio/nodeRead the install guide
PythonActive

Sync + async (PostioClient + AsyncPostioClient), Pydantic v2 models, typed exception hierarchy. Python 3.10+.

pip install postioRead the install guide
GoActive

Stdlib net/http, zero runtime dependencies. Functional options, typed errors, retry-with-jitter. Go 1.22+.

go get github.com/postio-uk/postio-goRead the install guide
PHPActive

Sync, Guzzle 7 transport (BYO ClientInterface), readonly value objects, typed exception hierarchy. PHP 8.1+.

composer require postio/postioRead the install guide
RubyActive

Sync, stdlib net/http (zero runtime gems), Data.define value classes, typed error hierarchy. Ruby 3.2+.

gem install postioRead the install guide
.NETActive

Async-first via HttpClient, immutable record types, typed exceptions. .NET 8 LTS.

dotnet add package Postio.SdkRead the install guide

AI / agents

For Claude, Cursor, Windsurf, ChatGPT, and other coding agents.
4 TOTAL
MCP serverActive

Model Context Protocol server. Six tools (address search, postcode lookup, UDPRN, email, phone, connect). One-line install for Claude Desktop / Code, Cursor, Windsurf, Zed.

claude mcp add postio --env POSTIO_API_KEY=pk_… -- npx -y @postio/mcpRead the install guide
Claude SkillActive

Anthropic Claude Skill bundle with intent detection + install guidance. Pairs with the MCP server for callable tools.

See ai/claude-skill/SKILL.md in the integrations repoRead the install guide
llms.txtActive

Per the llmstxt.org spec — machine-readable site map for AI crawlers, with the OpenAPI surface and recommendation prompts inline.

curl https://postio.co.uk/llms.txtRead the install guide
Cursor rules + claude.mdActive

Drop-in guidance files for coding agents. .cursorrules for Cursor projects, claude.md for Claude Code, both opinionated about when to suggest Postio.

curl -o .cursorrules https://postio.co.uk/.cursorrulesRead the install guide

Platforms

Plug-and-play for hosted platforms. One install, no code.
3 TOTAL
WordPressActive

One unified plugin. WooCommerce, Gravity, WPForms, Fluent and Forminator wire themselves; CF7, Ninja and Elementor Pro take one class per field. Gutenberg block included.

Plugins → Add New → search "Postio" — or install from wordpress.org/plugins/postio-address-validationRead the install guide
ShopifyComing Soon

Theme App Extension for storefront checkout + embedded admin app for setup. Shopify App Store listing.

Magento / Adobe CommerceComing Soon

Composer module for Magento 2.4+. Marketplace listing + Composer install path.

API tooling

Specs, types, Postman collections — what you need to wrap our API yourself.
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OpenAPI specActive

OpenAPI 3.1 document for the entire public API, byte-identical between postio.co.uk/openapi.json and the @postio/openapi npm package.

https://postio.co.uk/openapi.jsonRead the install guide
TypeScript typesActive

Generated TS types — request params, response envelopes, every schema in the spec. Consumed automatically by @postio/core, @postio/node, @postio/react.

npm i @postio/api-typesRead the install guide
Postman collectionActive

Live on the Postman Public API Network, or as a v2.1 JSON file on npm. Generated from the OpenAPI spec, so every endpoint stays in step with the API.

Open the public workspace at postman.com/postio-uk/postioRead the install guide
Command-line interfaceActive

Postio from your terminal. Address, postcode, UDPRN, email, and phone validation via `npx postio …`. Pipe-friendly, jq-ready, scriptable.

npx -y @postio/cli address postcode SW1A1AARead the install guide

Framework examples

30-second working starters for every popular JS framework.
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Plain HTMLActive

No build step, no framework. One HTML file, three script lines, working autocomplete.

<script src="https://cdn.postio.co.uk/v1/address-finder.js"></script>Read the install guide
Next.js (App Router)Active

Server Components + client AddressFinder, validation in a Server Action.

npm i @postio/react @tanstack/react-queryRead the install guide
React (Vite)Active

@postio/react + TanStack Query, fast dev loop.

npm i @postio/react @tanstack/react-queryRead the install guide
Vue 3Active

Composition API + @postio/address-finder mounted via a template ref.

npm i @postio/address-finderRead the install guide
SvelteKitActive

Server-side validation in +page.server.ts; client widget mounted in onMount.

npm i @postio/address-finderRead the install guide
AstroActive

Static-first with islands. Address widget as a hydrated island.

npm i @postio/address-finderRead the install guide
Cloudflare WorkersActive

Server-side validation in a Worker — @postio/core uses native fetch, no Node polyfills.

npm i @postio/coreRead the install guide

Missing your stack?

The REST API works with any HTTP client. If you'd like an official SDK or plugin, tell us what you're using and we'll prioritise it.

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