Staff Full-Stack Engineer

About Promptfoo

Promptfoo is the leading AI security testing platform, trusted by 250,000+ developers to build secure, reliable AI applications. Backed by Andreessen Horowitz and Insight Partners, we equip the world's largest enterprises with automated red teaming, vulnerability scanning, and continuous monitoring for LLM-based systems.

The Role

We're hiring a staff engineer to shape core features and scale our open-source toolkit into an enterprise-grade platform. You will speak with users, scope solutions, ship code across the stack, and raise our engineering bar. As a staff engineer, you'll also mentor team members and help establish technical standards that drive excellence across the organization.

What You'll Do

Product Discovery (20%)

Chat with ML, security, and DevOps teams to map pain points

Turn feedback into concise specs and quick prototypes

Full-Stack Development (40%)

Build React UI, Node.js / TypeScript APIs, and Python plug-ins

Own end-to-end delivery from design to docs

Quality & Performance (15%)

Add tests, refine types, and optimize evaluation pipelines

Improve CI / CD, linting, and release automation

Engineering Leadership & Mentorship (15%)

Mentor mid-level and senior engineers through code reviews, pair programming, and technical guidance

Set technical standards and best practices that elevate the entire engineering team

Lead architectural discussions and help the team navigate complex technical decisions

Foster a culture of learning through documentation, internal tech talks, and knowledge sharing

Open Source & Community (10%)

Review community PRs, mentor contributors, and polish docs

Demo new features in GitHub issues, Discord, and webinars

What We're Looking For

Must-Haves

6+ years building production software with staff-level impact

Strong TypeScript plus comfort with React, Node.js, and SQL

Experience shipping or integrating LLM-powered systems

Track record of open-source contribution or maintenance

Habit of writing tests and leaving code cleaner than you found it

Clear written and verbal communication; enjoy talking with customers

Thrive on ownership and quick iteration in an early-stage startup

Experience mentoring engineers and raising team capabilities through code reviews and technical guidance

Demonstrated ability to lead technical initiatives and influence engineering culture

Nice-to-Haves

Python, Rust, or Go experience

Background in security, red teaming, or developer tooling

Experience scaling event-driven or queue-based systems

What Makes This Role Unique

High Ownership : Drive product direction and architecture for a category-defining platform

Visible Impact : Your code ships to thousands of developers the same day

Learning : Work at the cutting edge of AI security and LLM evaluation

Culture : Remote-first, test-driven, community-minded team that values clean code

Leadership : Shape engineering standards and mentor talented engineers in a growing team