Senior Backend Engineer, Ruby — Remote AI-Driven Systems

GitLab; Poland; Remote; PLN 448,000 - 672,000; Full time

Job summary

GitLab is seeking a Senior Backend Engineer for the Plan: Spec-Driven Development team. You will own backend work across flows, APIs, and evaluation systems, leveraging Ruby on Rails, Python, PostgreSQL, GraphQL, and the Duo Agent Platform to deliver agent-driven workflows.

You’ll join a small, distributed, all-remote team driving high-visibility product bets. In your first year, lead major features end-to-end, mentor peers, and influence technical decisions across agent workflows and evaluation

Qualifications

• Experience with Ruby on Rails in a large production codebase.
• Backend engineering background with end-to-end feature ownership.
• Strong API design and data modeling skills.

Responsibilities

• Lead backend features from early product discussions through design, implementation, rollout, and post-launch learning.
• Build the flows, APIs, and data models behind agent-generated work items and durable specifications.
• Develop evaluation and benchmarking systems for workflow quality, token cost, and success rate.
• Use Ruby on Rails and Python to build reliable production systems with PostgreSQL and GraphQL.
• Collaborate with product, design, engineers, and users to shape scope and trade-offs.
• Coordinate multi-person projects in GitLab's async, all-remote environment.
• Mentor engineers and guide technical direction across Plan group and AI initiatives.
• Iterate in short cycles with demos and user feedback to steer next steps.

Skills

Ruby on Rails

Python

Product mindset

End-to-end ownership

API design

Team collaboration

Tools

PostgreSQL

GraphQL

GitLab Duo Agent Platform

Job description

GitLab is seeking a Senior Backend Engineer for the Plan: Spec-Driven Development team. You will own backend work across flows, APIs, and evaluation systems, leveraging Ruby on Rails, Python, PostgreSQL, GraphQL, and the Duo Agent Platform to deliver agent-driven workflows.

You’ll join a small, distributed, all-remote team driving high-visibility product bets. In your first year, lead major features end-to-end, mentor peers, and influence technical decisions across agent workflows and evaluation