You will get your OpenAI API or LLM integration fixed in Node.js & Next.js
Project details
Are your OpenAI or AI API calls failing, timing out on Vercel, or breaking your Next.js/Node.js backend? Integrating LLMs into production requires careful handling of rate limits, serverless timeouts, streaming responses (SSE), and strict JSON validation.
I am a Senior Full-Stack Engineer specializing in TypeScript, Node.js, and AI API integrations. I will diagnose your API issues and deliver a reliable, production-ready AI workflow.
Common issues I resolve:
• Vercel Serverless Function timeouts during long LLM responses
• Broken real-time response streaming (Server-Sent Events / SSE)
• Unhandled OpenAI rate limits (429 errors) and network retries
• Invalid JSON output or schema parsing errors (Zod / Structured Outputs)
• Missing API error boundaries & async/await state bugs
• Saving AI generation results to Supabase/PostgreSQL
What you will receive:
• A clean, fully tested API endpoint or Server Action
• Proper async error handling, retries, and timeout guards
• Optimized token management & payload structures
• Concise code comments and documentation
Send over your repository or API specs, and let's get your AI features working smoothly! Live demo: saas.shlykoff.com.
I am a Senior Full-Stack Engineer specializing in TypeScript, Node.js, and AI API integrations. I will diagnose your API issues and deliver a reliable, production-ready AI workflow.
Common issues I resolve:
• Vercel Serverless Function timeouts during long LLM responses
• Broken real-time response streaming (Server-Sent Events / SSE)
• Unhandled OpenAI rate limits (429 errors) and network retries
• Invalid JSON output or schema parsing errors (Zod / Structured Outputs)
• Missing API error boundaries & async/await state bugs
• Saving AI generation results to Supabase/PostgreSQL
What you will receive:
• A clean, fully tested API endpoint or Server Action
• Proper async error handling, retries, and timeout guards
• Optimized token management & payload structures
• Concise code comments and documentation
Send over your repository or API specs, and let's get your AI features working smoothly! Live demo: saas.shlykoff.com.
Programming Languages
JavaScript, TypeScriptCoding Expertise
Performance OptimizationWhat's included
| Service Tiers |
Starter
$85
|
Standard
$160
|
Advanced
$275
|
|---|---|---|---|
| Delivery Time | 1 day | 2 days | 3 days |
Number of Revisions | 1 | 2 | 3 |
Bug Investigation | |||
Fix Documentation | |||
Detailed Code Comments |
Optional add-ons
You can add these on the next page.
Fast Delivery
+$50
Real-Time Response Streaming (SSE / UI Hooks)
+$40
Save AI Logs & Outputs to Supabase / PostgreSQL
+$35
Strict JSON Output & Zod Schema Validation
+$30Frequently asked questions
About Vasilii
Full stack Software Engineer
Tbilisi, Georgia - 5:43 pm local time
Over the years I've built backend systems, databases, and APIs across a range of setups: REST and GraphQL APIs, microservices and distributed systems, cloud infrastructure, and containerized deployments (Docker). On the frontend, I work primarily with Next.js and Vercel. I also handle two areas that tend to break in production if done carelessly: payment systems (Stripe — Checkout, subscriptions, webhook handling) and database security (PostgreSQL/Supabase Row Level Security, multi-tenant data isolation). More recently I've been adding OpenAI/LLM integrations into existing products for teams adding AI features.
Recent example: I built and shipped a full SaaS application end-to-end — authentication, org-based RLS, Stripe subscriptions, gated features, deployed live — to demonstrate how these pieces fit together in one working product. Demo and source code are in my portfolio below.
Before Upwork, I co-founded and served as CTO at MySoft, leading architecture, technical strategy, and delivery for custom backend systems and infrastructure across multiple industries. I started programming in international ACM competitive programming olympiads, which is where the habit of writing precise, well-tested code came from.
Whether it's a backend API, a database/RLS issue, a broken Stripe integration, a Next.js deployment problem, or wiring an LLM into your product — send me the details and I'll tell you honestly whether I can help and how long it'll take.
Steps for completing your project
After purchasing the project, send requirements so Vasilii can start the project.
Delivery time starts when Vasilii receives requirements from you.
Vasilii works on your project following the steps below.
Revisions may occur after the delivery date.
API & Endpoint Audit
I review your API setup, payload structure, and error logs to locate the issue.
Debugging & Refactoring
I fix the underlying code, add proper error handling, schema validation, and test edge cases.