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You will get Third-Party API Integration for Your Node.js Backend

Sos M.Status: Offline
Sos M. Sos M.
5.0
Rising Talent
Preview imagePreview imagePreview imagePreview image

Let a pro handle the details

Buy Web Application Programming services from Sos, priced and ready to go.
Sos M.Status: Offline
Sos M. Sos M.
5.0
Rising Talent
Preview imagePreview imagePreview imagePreview image

Let a pro handle the details

Buy Web Application Programming services from Sos, priced and ready to go.

Project details

I connect third-party APIs to your existing backend — payment systems, CRMs, Google Sheets, QuickBooks, scheduling tools, or any service with a REST API.

I built Spring (getspring.io), a production SaaS platform that integrates with QuickBooks, Google Sheets, and Google OAuth. So this isn't theory — I've built, deployed, and maintained real API integrations that handle live data every day.

Every integration includes secure authentication setup, proper error handling, retry logic for failed requests, rate limiting to stay within API limits, and clear documentation so your team knows exactly how everything works.

Stack: Node.js, TypeScript, Express, PostgreSQL
Programming Languages
JavaScript, TypeScript
Coding Expertise
Security
What's included
Service Tiers Starter
$150
Standard
$300
Advanced
$500
Delivery Time 3 days 5 days 7 days
Number of Revisions
123
Design Customization
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Content Upload
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Responsive Design
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Source Code
Optional add-ons You can add these on the next page.
Fast Delivery
+$50 - $100

Frequently asked questions

5.0
1 review
100% Complete
(1)
1% Complete
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UO

Uri O.
5.00
Apr 10, 2026
AI Developer for Financial and Customer Management Tools Fabulous brilliant hard working and diligent fullstack engineer will work with Sos again soon.
Sos M.Status: Offline

About Sos

Sos M.Status: Offline
AI Agent & Backend Engineer | MCP, LLM Pipelines, Node/TypeScript
5.0  (1 review)
Lviv, Ukraine - 6:02 am local time
I build AI agent systems and the backends they run on.

Right now I run production work for a short-term rental company (US): AWS Lambda services, an LLM extraction pipeline on AWS Bedrock that turns messy booking data into structured fields, and an agent runtime with a Slack bot that staff use daily. Node.js, TypeScript, NestJS, Prisma, Postgres/MySQL/Mongo, Docker, GitHub Actions.

I also built and shipped Maestro — my own orchestration app for AI coding agents. Electron desktop client, NestJS + PostgreSQL API on a VPS, migrations, schedules, persistent state. It drives Claude Code and Codex agents against real repositories. I use it every day on client work.

Hire me for:
→ AI agents that do real work — tool use, MCP servers, orchestration, guardrails, not demos
→ LLM pipelines: extraction, classification, structured output, evals
→ Backends and APIs: REST, OAuth 2.0 / JWT / RBAC, third-party integrations, Postgres + Prisma
→ Getting it deployed: AWS, Docker, VPS, CI/CD

Before code I ran a manufacturing business and a food brand into national retail. That's why I ask what the thing is for before I build it, and why I tell you when a feature isn't worth the money.

Steps for completing your project

After purchasing the project, send requirements so Sos can start the project.

Delivery time starts when Sos receives requirements from you.

Sos works on your project following the steps below.

Revisions may occur after the delivery date.

API Review & Planning

I review the API docs, define which endpoints we need, map out the data flow, and confirm everything with you before writing any code

Authentication & Connection

Set up secure authentication (OAuth, API keys, or tokens depending on the service) and verify the connection is working

Review the work, release payment, and leave feedback to Sos.