I will integrate a third-party REST API into your website or app

I will integrate a third-party REST API into your website or app — clean, secure, well-tested wiring between your product and the service you depend on. Built to handle real-world errors, not just the happy path.

What you get

You bring the API (a payment gateway, CRM, shipping provider, weather feed, AI service, booking system, internal microservice — anything that speaks REST), and I connect it to your existing website or application so the data flows reliably in both directions. This is hands-on development work delivered as committed code in your repository, not a template or a generic plugin.

• Working integration between your app and the chosen REST API, covering the specific endpoints and operations you need (authentication, fetching data, creating/updating records, webhooks where the API offers them).
• Authentication wired correctly — API keys, OAuth 2.0 flows, bearer tokens, HMAC request signing, or basic auth, configured per the provider's docs and stored as environment variables, never hard-coded.
• A typed/structured client layer so calls live in one place instead of being scattered through your codebase — easy to reuse, mock, and maintain.
• Robust error handling: timeouts, retries with backoff for transient failures, rate-limit awareness, and graceful fallbacks so a third-party hiccup doesn't crash your page.
• Request/response mapping that transforms the API's payloads into the shape your app actually uses (DTOs, view models, or database records).
• Pagination, filtering, and sorting handled where the endpoint supports it, so large datasets don't break.
• Secrets and config externalized into .env / your platform's secret manager, with a documented .env.example.
• A short README / handover note explaining what was added, how to configure credentials, and how to run it.
• Sandbox/test-mode wiring first where the provider offers it, so we validate against test credentials before touching anything live.

I work in your stack — JavaScript/TypeScript (Node, Express, Next.js, React), Python (Django, Flask, FastAPI), PHP (Laravel), and most common web frameworks. If you have an existing codebase, I match its conventions, linting, and folder structure so the integration looks native, not bolted on.

Plans

Feature	Basic	Standard	Premium
Endpoints integrated	1 core endpoint	Up to 4 endpoints	Up to 10 endpoints / full flow
Authentication setup	API key / token	OAuth or signed requests	Complex multi-step auth + token refresh
Error handling & retries	Basic	Retries + rate-limit handling	Full resilience + logging
Webhook handling	—	1 webhook	Multiple webhooks + verification
Data mapping to your models	Simple	Yes	Yes, with caching
Automated tests	—	Key paths	Comprehensive
Documentation / handover	Brief note	README	README + inline docs
Revisions	1	2	3

If your needs don't fit neatly into a tier, message me with the API name and what you want it to do, and I'll tell you honestly which plan fits — or propose a custom scope.

How it works

1. You share the details. Send me the API's documentation link, what you want it to do (the specific actions and data), your repository or codebase, and access to test/sandbox credentials.
2. I confirm scope. I read the docs, identify the exact endpoints and auth method, flag any limits or gaps, and confirm the deliverable with you before writing code — no surprises.
3. Build against sandbox. I implement the client layer, auth, and error handling using the provider's test environment so nothing live is affected during development.
4. Wire it into your app. I connect the integration to your actual UI, backend, or data layer, mapping responses into the structures your app uses.
5. Test and review. I verify the happy paths and the failure paths (bad credentials, timeouts, rate limits, malformed responses), then walk you through what was built.
6. Handover. You get the committed code, configuration instructions, and a clear note on how to swap test credentials for production keys when you're ready to go live.

Why choose this

I focus on the parts that separate a demo from a production integration: what happens when the API is slow, returns a 429, changes a field, or rejects your token mid-session. Anyone can paste a fetch call from the docs; the value is in the layer around it — secure credential handling, sensible retries, clear errors surfaced to your app, and code your future self (or your team) can actually maintain.

I keep secrets out of your source control, follow the provider's official documentation rather than guessing, and write the integration so it's testable and isolated. You stay in control: you keep the API account, the keys, and full ownership of the code.

Who it's for / use cases

• Founders and small teams who picked a SaaS provider (Stripe, Twilio, SendGrid, HubSpot, Shopify, OpenAI, a shipping or maps API) and need it wired into their product properly.
• Agencies needing an extra pair of hands to connect a client's app to a partner's API on deadline.
• Developers who have a working app but want the integration done cleanly so they can focus elsewhere.
• Businesses syncing data between systems — pushing orders to a fulfillment service, pulling inventory, posting leads to a CRM, or aggregating data from multiple sources into one dashboard.
• Anyone stuck on an auth flow (OAuth, signed requests, token refresh) that the docs make sound simpler than it is.

FAQ

Q: Which APIs do you work with? Any service that exposes a REST/HTTP JSON API with documentation. That includes payments, messaging, email, CRMs, e-commerce platforms, AI/LLM services, mapping, weather, internal company APIs, and more. If you're unsure, send the docs link and I'll confirm.

Q: Do I need to provide API credentials? Yes. You keep ownership of the account and the keys. I'll need test/sandbox credentials to build and verify, and you apply your production keys (or share them securely) when you're ready to go live. I store everything as environment variables, never in code.

Q: What if the API doesn't have a sandbox? Many do; some don't. If there's no test mode, I build defensively and we run a careful, limited validation against the live endpoint — using read-only or low-risk calls first, and coordinating with you before anything that creates or changes real data.

Q: Can you also build the UI or feature around the integration? This service covers the integration layer — connecting the API and getting data flowing into your app. Light UI wiring to display or submit that data is included. Larger front-end or feature work is something we can scope separately; just ask.

Q: My API isn't strictly REST — it's GraphQL or SOAP. Can you help? This gig is scoped to REST APIs. I do work with GraphQL and other styles too, so message me first and I'll set up a fitting custom scope rather than forcing it into the wrong plan.

Q: How do you handle errors and downtime from the third party? I add timeouts, retries with exponential backoff for transient failures, rate-limit handling, and clear error responses so your app degrades gracefully instead of crashing when the provider has a bad moment.

Q: Will the code be maintainable by my own team? Yes. I isolate the integration into a clear client layer, follow your existing code conventions, externalize configuration, and include documentation so anyone on your team can read, extend, or debug it later.

Q: What do you need from me to start? The API documentation link, a description of exactly what you want it to do, access to your codebase/repository, and test credentials. The more specific you are about the data and actions you need, the faster and cleaner the result.