Integrations
Integrate Constaia with any stack: JavaScript, PHP, Python, Go, Java, .NET, Ruby, no-code tools and AI agents. Full code with uploads, errors and webhooks.
Every integration follows the same pattern:
- The user uploads or photographs the document in your site or app (with the widget or your own form).
- The file reaches your backend.
- Your backend calls Constaia with the key, deciding
expectandchecks. - You store the verdict and, for async or batch analyses, receive the result by webhook.
The key (ck_live_… or ck_test_…) lives only on the server: never in the browser, a mobile app or a repository.
Every guide includes installation, environment variables, complete code, error handling and a webhook with
signature verification. You can try them all for free with a test key and the test files.
Official SDKs: JavaScript/TypeScript, PHP and Python. For other languages, the REST API is simple and the OpenAPI spec lets you generate a client.
Coming soon
Official Go, Java, Ruby and .NET SDKs, an official n8n node, hosted verification links
(POST /v1/verification-links) and publishable browser keys. Meanwhile, the guides below work with the REST API.
JavaScript and TypeScript
Node.js
Script and node:http server with the SDK.
Express
Uploads with multer and a webhook with express.raw.
Fastify
@fastify/multipart and a raw-body webhook.
Hono
Routes on Node, Bun or Deno.
NestJS
Module, service, FileInterceptor and a rawBody webhook.
Koa
Multipart upload and webhook.
Next.js
Route handler, server action and widget.
Nuxt
Server route and widget with Vue.
SvelteKit
+server.ts, private env vars and widget.
Remix / React Router
Action with formData and a resource route for webhooks.
Astro
API endpoint with an SSR adapter.
SolidStart
API route and web component.
Angular
Custom element with your backend.
React
Widget with ConstaiaUpload and useConstaiaUpload.
Vue
Component, plugin and isCustomElement.
Svelte
Web component with listeners.
React Native / Expo
Camera photo to your backend.
Electron
IPC to the main process and upload to your backend.
Bun
Bun.serve with the SDK.
Deno
Deno.serve with npm:@constaia/sdk.
Vercel Edge and Netlify Edge
Edge functions with the key on the server.
AWS Lambda
Function URL or API Gateway, S3 and webhooks.
Google Cloud Functions
functions-framework and rawBody.
Firebase Functions
onRequest, Storage trigger and secrets.
Supabase Edge Functions
Deno, Storage and Supabase secrets.
PHP
PHP
Form, upload and webhook without a framework.
Laravel
Facade, validation rule, queues and webhooks.
Symfony
Service, controller, Messenger and webhook.
WordPress
Plugin with a shortcode and a REST route.
Drupal
Module with Form API and a webhook route.
CodeIgniter
Controller, service and webhook.
Slim
PSR-7, upload and webhook.
Python
Python
Scripts, pytest and the httpx alternative.
Django and DRF
View, APIView and webhook.
Flask
request.files and webhook.
FastAPI
UploadFile with the async client.
Celery
Tasks with retries and idempotency.
Other languages
Ruby on Rails
Service object, ActiveJob and webhook.
Go
net/http, multipart and hmac.
Java / Spring Boot
RestClient, MultipartFile and webhook.
Kotlin / Ktor
Ktor client and server.
C# / ASP.NET Core
Typed HttpClient and IFormFile.
Rust
reqwest and axum.
Elixir / Phoenix
Req, Plug.Upload and raw body.
Swift / Vapor
Vapor server with multipart.
Dart / Flutter
Flutter app with your backend.
No-code and automation
n8n
HTTP Request node and Webhook.
Make
HTTP module and custom webhook.
Zapier
Webhooks by Zapier.
Power Automate
HTTP action with base64.
Google Apps Script
Sheets with UrlFetchApp.
Airtable
Automation script with attachments.
Retool
REST resource and File Input.
AI and agents
Function calling
Constaia as a tool in OpenAI and Anthropic.
LangChain and LlamaIndex
A tool for your agents.
MCP
Claude, Cursor, VS Code and Windsurf with @constaia/mcp.
Next steps
Proof of address with utility bills
Verify a US utility bill or bank statement as proof of address, with its recency, the account holder and the ZIP code, and compare the address with your form.
Node.js
Use Constaia from plain Node.js: a script that analyses local files and a node:http server with an upload route and a verified webhook.