Backend Engineer - AI Coding Agent

mercor; United States; Remote; USD 99,000 - 135,000; Part time

Job summary

Mercor is seeking a Backend Engineer to work on coding agent experiences in a fully remote contract role. You will leverage frontier AI coding agents to tackle complex backend tasks and evaluate code quality across models.

You will review outputs, identify bugs and architectural tradeoffs, and contribute to scalable API and distributed systems work. The role emphasizes independent, asynchronous work and strong engineering judgment.

Qualifications

• 2+ years of professional backend engineering experience.
• Experience building APIs, distributed systems, microservices, backend platforms, or databases.
• Regular use of AI coding agents such as Cursor, Claude Code, Codex, Windsurf, Gemini CLI, or similar tools.
• Ability to evaluate model-generated code and identify bugs, edge cases, and architectural tradeoffs.

Responsibilities

• Use frontier AI coding agents to complete and evaluate complex engineering tasks.
• Review model-generated code for correctness, quality, maintainability, and performance.
• Identify bugs, edge cases, and failure modes in model outputs.
• Compare outputs from multiple frontier models and assess their strengths and weaknesses.
• Apply professional engineering judgment to realistic backend engineering scenarios.
• Work independently and asynchronously to meet deadlines while improving AI model performance.

Skills

API development

Distributed systems

Microservices

Backend platforms

Databases

Code review

Tools

Cursor

Claude Code

Codex

Windsurf

Gemini CLI

Job description

About the job

Mercor connects elite creative and technical talent with leading AI research labs. Headquartered in San Francisco, our investors include Benchmark , General Catalyst , Peter Thiel , Adam D'Angelo , Larry Summers , and Jack Dorsey . Position: Backend Engineer (Coding Agent Experience) Type: Contract Compensation: $85/hour Location: Remote Role

Role Responsibilities

• Use frontier AI coding agents to complete and evaluate complex engineering tasks.
• Review model-generated code for correctness, quality, maintainability, and performance.
• Identify bugs, edge cases, and failure modes in model outputs.
• Compare outputs from multiple frontier models and assess their strengths and weaknesses.
• Apply professional engineering judgment to realistic backend engineering scenarios.
• Work independently and asynchronously to meet deadlines while improving AI model performance.

Qualifications

• 2+ years of professional backend engineering experience.
• Experience building APIs , distributed systems, microservices, backend platforms, or databases.
• Regular use of AI coding agents such as Cursor, Claude Code, Codex, Windsurf, Gemini CLI, or similar tools.
• Ability to evaluate model-generated code and identify bugs, edge cases, and architectural tradeoffs.

Preferred

• Experience working on large-scale production systems.

Compensation & Legal

• $400 per accepted task.
• Typical tasks take approximately 1–3 hours after ramp-up.
• No fixed task limits.
• Compensation is tied to accepted work.