Senior Backend Engineer — Ruby & AI-Driven Plans (Remote)

GitLab Inc.; Poland; Remote; PLN 272,000 - 408,000; Full time

Job summary

GitLab Inc. is seeking a Senior Backend Engineer in Poland to join the Plan: Spec-Driven Development team and help build the intent-to-code loop—from stated intent to refined work item, plan, and mergeable code.

You will own early-stage backend work across flows, APIs, data models, and evaluation systems using Ruby on Rails, Python, PostgreSQL, GraphQL, and an AI gateway. You will join a small, distributed, all-remote team working on a high-visibility product bet, with the opportunity to lead

Qualifications

• Strong Ruby on Rails experience in a large production codebase and production experience with Python.
• Experience driving substantial projects with several engineers over multiple months, with clear user or business outcomes.
• A product mindset and experience owning features end to end, including shaping scope, making trade-offs, engaging with users, and learning from adoption after launch.
• A full stack background with a current focus on backend engineering, plus the ability to read modern frontend code and design effective APIs.
• Strong application programming interface design and structured query language fundamentals.
• The ability to work independently, collaborate across functions and regions, and support others through technical leadership and mentoring. Experience with GraphQL, PostgreSQL performance at scale, or building and evaluating large language model or agent systems is helpful but not required.

Responsibilities

• Lead backend features from early product discussions through technical design, implementation, rollout, and post-launch learning.
• Build the flows, application programming interfaces, and data models behind agent-generated work items, implementation plans, durable specifications, and mergeable code.
• Develop evaluation and benchmarking systems that measure workflow quality, token cost, and success rate.
• Use Ruby on Rails and Python to build reliable production systems, with PostgreSQL, GraphQL, representational state transfer, GitLab Duo Agent Platform, large language model application programming interfaces, and an artificial intelligence gateway.
• Collaborate directly with product, design, engineers, design partners, and users to shape scope and make practical trade-offs.
• Coordinate multi-person projects across the team and communicate decisions clearly in GitLab's asynchronous, all-remote environment.
• Mentor other engineers and contribute to technical direction across the Plan group and related artificial intelligence initiatives.

Skills

Ruby on Rails

Python

Project leadership

Full stack backend

API design

SQL fundamentals

Mentoring

Tools

GraphQL

PostgreSQL

GitLab Duo Agent Platform

LLM APIs

Job description

GitLab Inc. is seeking a Senior Backend Engineer in Poland to join the Plan: Spec-Driven Development team and help build the intent-to-code loop—from stated intent to refined work item, plan, and mergeable code.

You will own early-stage backend work across flows, APIs, data models, and evaluation systems using Ruby on Rails, Python, PostgreSQL, GraphQL, and an AI gateway. You will join a small, distributed, all-remote team working on a high-visibility product bet, with the opportunity to lead