Senior Backend Engineer / Tech Lead (Node.js, TypeScript) Commit Offshore $$$$

Madfish

Madfish

Software Engineering

Ukraine · Europe

Posted on May 10, 2026

About the Role

We're looking for a hands-on Senior Backend Engineer / Tech Lead to own core backend development on the Backslash platform. This is a high-ownership role — you'll drive architectural decisions, implement customer-facing features, and keep systems performant and secure at scale. The right person is analytical, self-sufficient, and comfortable working end-to-end with minimal hand-holding.

Key Responsibilities

  • Take full ownership of backend development in Node.js and TypeScript
  • Lead architectural improvements and simplification of existing systems
  • Implement and deliver customer feature requests end-to-end
  • Ensure high performance — memory optimization, throughput, and scalability
  • Maintain strong application security practices (AppSec) across the codebase
  • Participate in an on-call rotation (week-by-week basis)
  • Guide technical decisions and mentor team members as a Tech Lead
  • Collaborate cross-functionally with product, security research, and customer teams

Requirements

  • 6+ years of backend development experience
  • Deep expertise in Node.js and TypeScript
  • Experience in or readiness to step into a Tech Lead role
  • Strong analytical and problem-solving skills — a must
  • Solid understanding of application security (AppSec) principles and practices
  • Hands-on experience with memory optimization and performance tuning
  • Able to work independently, own tasks from spec to production
  • English B2+ — clear written and verbal communication

Nice to Have

  • Experience in an AppSec-focused product environment — significant advantage
  • Familiarity with security packages and vulnerability management tooling (e.g. npm audit, Snyk, OSV, SAST/SCA concepts)
  • Background in customer-facing or feature-driven development
  • Exposure to code analysis, static analysis, or software supply chain security concepts