Stafnear

This is a new initiative within a product company, and you'll be the only Node.js developer on the team. You'll take full ownership of the product's backend—from making architectural decisions to delivering features and supporting production.

Product

A B2B SaaS platform used by large media groups to manage and run digital advertising campaigns across their websites. The platform handles real-time ad serving, processes large volumes of impression and engagement events, provides heatmaps, click tracking, engagement analytics, and supports both desktop and mobile environments.

Team

The development team consists of 11 people, including the CTO, Product Director, Project Manager, QA Engineers, and Software Developers.

What You'll Do

• Design and own the backend architecture
• Build and maintain backend services using Node.js and TypeScript
• Design scalable data models and APIs
• Integrate services with AWS infrastructure (EC2, S3, Lambda)
• Debug, optimize, and maintain production services

What We're Looking For

• 4+ years of backend development experience; a true Senior Engineer who is confident making architectural decisions independently
• Strong expertise in Node.js and JavaScript/TypeScript
• Deep understanding of asynchronous programming and REST APIs
• Experience designing backend architectures and scalable services
• Experience with AWS (EC2, S3, Lambda)
• Experience with Docker and containerization
• English level B2+ (the technical interview is conducted in English)

We're looking for a Node.js Developer in Odesa.

You'll lead the migration of our core product to Node.js, rewriting the backend from scratch. At the beginning, you'll be driving the migration independently.

The company develops its own products, with customers including Disney, Carlsberg, and Lexus.

You'll be the first Node.js developer on the team.

What you'll do

• Design the backend architecture in Node.js
• Build backend services using Node.js and TypeScript
• Design scalable data models and APIs
• Integrate services with AWS infrastructure (EC2, S3, Lambda)
• Debug and optimize production services

We're looking for someone with

• 4-6 years of backend development experience with Node.js
• Strong JavaScript / TypeScript skills
• Solid understanding of asynchronous programming and REST APIs
• Experience designing backend architectures and scalable services
• AWS experience
• English level B2+ (the technical interview and daily communication with the CTO are conducted in English)

What we offer

• 20 working days of paid vacation + 5 paid sick days
• Private medical insurance (starting from the third month)
• Official employment, tax coverage, and accounting support

We're building a traffic arbitrage / performance-marketing platform and are now refining it beyond MVP. You'll work on the core backend: tracking and redirect services, billing logic, webhook integrations, and database evolution on a live system. Short engagement (several weeks), part-time, post-payment.

What you'll work on

• Server-side tracking / redirect services under load and latency SLA — 302 handling, GeoIP lookup, fingerprinting, event logging
• Webhook / postback integrations — signed webhooks (HMAC), idempotency, reliable event ingestion from an external partner (broker)
• Financial / billing logic — commission and payment calculation, monetary arithmetic with Decimal (never float), state machines (pending / approved / paid / hold), chargebacks / clawbacks, idempotent recalculation
• Database schema design and evolution with backward compatibility — migrations on a live system

• Application-level security — webhook signing, JWT / secrets management, no PII in logs

   

Must-have stack

• Python 3.11+ with async (async/await, asyncio)
• FastAPI, Pydantic
• PostgreSQL at an advanced level — JSONB, indexing, query optimization on large tables, writing migrations
• SQLAlchemy 2.x + Alembic (or equivalent ORM + migrations)
• Redis, Celery

Strong plus

• Domain experience in iGaming / forex / trading / affiliate / adtech / performance marketing - understanding of GGR, FTD, postbacks, click-tracking, sub-ID, RevShare / CPA / Hybrid
• Cloudflare API (zones, DNS, DNSSEC, SSL, proxy), or solid DNS/SSL knowledge and experience with infrastructure APIs
• Anti-fraud / rules engines — velocity checks, fingerprint deduplication, IP / ASN / GEO analysis
• Experience with nginx, PM2, S3-compatible storage

Requirements

• Level: Middle+
• English: not critical

Conditions

• Duration: several weeks
• Workload: part-time
• Payment format: post-payment