You will get API Integration: Connect Your Tools & Automate Your Data Workflows
Project details
Need two systems to talk to each other? I connect any API to your app, site or database and make the data flow automatically.
12,900+ GitHub stars | I run a data toolkit with 43 endpoints across 15 sources, with automatic failover
What I integrate:
Third-party APIs into your app, site or backend (REST, GraphQL, JSON, XML)
Payment gateways: Stripe, PayPal, and regional providers
CRM, Sheets, Airtable, Notion and webhook automations
AI APIs: OpenAI and Claude into your existing product
Custom REST API built from scratch when you need one
I do not just wire it up and leave. You get retries, error handling and a written note on every endpoint, so it keeps working when a source changes or rate-limits you.
Why work with me:
I run my own multi-source data services, so broken and rate-limited APIs are my daily work
You keep your own API keys and accounts. I document every access point
You work with the developer directly. No account manager
Async by design: send the docs and the goal, get written progress. No meetings
Full source code, always yours
Send me the two systems you want connected and what should happen, and I will confirm scope and package in my first reply.
12,900+ GitHub stars | I run a data toolkit with 43 endpoints across 15 sources, with automatic failover
What I integrate:
Third-party APIs into your app, site or backend (REST, GraphQL, JSON, XML)
Payment gateways: Stripe, PayPal, and regional providers
CRM, Sheets, Airtable, Notion and webhook automations
AI APIs: OpenAI and Claude into your existing product
Custom REST API built from scratch when you need one
I do not just wire it up and leave. You get retries, error handling and a written note on every endpoint, so it keeps working when a source changes or rate-limits you.
Why work with me:
I run my own multi-source data services, so broken and rate-limited APIs are my daily work
You keep your own API keys and accounts. I document every access point
You work with the developer directly. No account manager
Async by design: send the docs and the goal, get written progress. No meetings
Full source code, always yours
Send me the two systems you want connected and what should happen, and I will confirm scope and package in my first reply.
Programming Languages
JavaScript, Python, TypeScriptCoding Expertise
Performance Optimization, SecurityWhat's included
| Service Tiers |
Starter
$65
|
Standard
$245
|
Advanced
$795
|
|---|---|---|---|
| Delivery Time | 2 days | 5 days | 12 days |
Number of Revisions | 2 | 3 | 5 |
Number of Pages | 1 | 3 | 8 |
Design Customization | - | - | - |
Content Upload | - | - | - |
Responsive Design | - | - | - |
Source Code |
Optional add-ons
You can add these on the next page.
Fast Delivery
+$35 - $120
Additional Revision
+$49Frequently asked questions
About Sizhen
Claude Code & MCP Developer | AI Agents, Automation & API Integration
Kowloon City, Hong Kong - 8:58 am local time
My open-source projects have earned 12,900+ stars and 2,600+ forks, all built in the last few months. Forks matter more than stars: 2,600+ means people run my code in production, not just bookmark it. Every project is public on GitHub — you'll find them in my Portfolio below, with the numbers you can verify yourself.
Most "AI agent developers" hand you a fragile n8n flow or a LangChain demo that breaks the first time real data hits it. I build systems that stay up. My a-stock-data toolkit (7,600+ stars) pulls from 15 data sources across 43 endpoints with automatic failover — when one source dies, it reroutes instead of crashing. That is the engineering I bring to your project.
The domain of my public work happens to be financial data, but the engineering — multi-source pipelines, agent orchestration, MCP servers — transfers to any industry.
WHAT I BUILD
🔌 MCP Servers & Claude Code Setups
I build Model Context Protocol servers so your agent reaches any tool, API, or database through one clean interface. Broken Claude Code configs — missing MCP integrations, hooks, permission models, runaway token use — are things I fix routinely.
🤖 AI Agents & Multi-Agent Systems
Agents that plan, call tools, and take real actions in your stack. My TradingAgents framework (2,500+ stars) runs 7 agents that debate and reach a decision together, with risk checks built in.
⚙️ Workflow Automation
n8n, Make, and custom Python for the manual work that eats your team's week — lead routing, CRM sync, reporting, document processing. Built to be maintained, not to fall over in a month.
🔗 API Integration
Connecting tools that don't talk to each other, with webhooks and custom code that survives rate limits, retries, and the source going down.
🛠 Fixes for AI / Vibe-Coded Apps
If an app from Lovable, Bolt, or Cursor is half-working, I clean up the code and get it shipped — and you own it, clean, afterward.
TECH STACK
AI/LLM: Claude, OpenAI, MCP, RAG, LangChain
Backend: Python (FastAPI), Node.js, TypeScript
Automation: n8n, Make, custom scripts
Data: PostgreSQL, Supabase, vector databases, multi-source pipelines
Frontend: React, Next.js
HOW I WORK
I work async and text-first. You get clear written updates, clean documented code, and a recorded walkthrough at handoff, so you can run and maintain the system after I'm done. No standing meetings, no black boxes — progress you can see at every step.
If you have an AI system that needs building, or one that's already broken, send me the details. I'll tell you exactly how I'd approach it before you spend a dollar.
Steps for completing your project
After purchasing the project, send requirements so Sizhen can start the project.
Delivery time starts when Sizhen receives requirements from you.
Sizhen works on your project following the steps below.
Revisions may occur after the delivery date.
Send the two systems and the goal
You tell me the two systems, share the API docs, and what should happen. I confirm scope and package in my first reply.
Map the integration
I map the endpoints, auth and data flow, and agree the exact scope with you in writing.