Job Description

As a Design Engineer at Trajectory, you will craft the product experience that makes continual learning legible and intuitive.

You will own the visualization, interaction, and developer experience surfaces that help customers understand, debug, and trust continually improving models. This includes trajectory visualization, evaluation workflows, monitoring dashboards, and the core product interfaces that sit on top of our leading RL infrastructure.

You’ll work directly with the founders and industry-leading design partners (Series B+ AI vertical product companies) to translate frontier RL systems into a clean, developer-first product experience. You will help define the visual language, interaction patterns, and product philosophy of Trajectory.

We are building the interface for continual learning. This role sets that bar.

Note: Some travel may be required - we work closely with design partners across the world.

Required Qualifications

• Strong frontend or design engineering experience (TypeScript/React or similar)

• Experience building polished, production user interfaces

• Strong product taste and clear opinions about what makes software feel great - with the craft to back it up

• Experience building AI-powered products or agent systems - you actively experiment with new frameworks for fun!

Preferred

• Experience building data visualization or complex technical UIs

• Experience with observability or debugging interfaces

• Background at high-craft product companies or developer tooling startups

• Experience working closely with designers or operating as a design-minded engineer

About Trajectory

Trajectory is a research and product lab creating the platform for continual learning.

AI is the most capable software ever built, and the least able to learn. Every valuable correction and edit that happens in a product evaporates at the next session. A few teams have closed this gap by hand-coupling their models to their products: Composer, Claude Code, Windsurf SWE-1.

Trajectory is the first scalable approach for every company: our platform unlocks the signal already sitting in product use, so companies can continuously post-train large-scale agentic models that outperform the frontier. Working with leading AI companies, including Decagon, Clay, Harvey, Mercor, and Rogo.

Founded by researchers from Deepmind, OpenAI, Meta, Apple, Amazon, and Scale. $15M led by Conviction, with Fei-Fei Li, Jeff Dean, and founders of Notion, Braintrust, Modal, Hugging Face, and Dropbox.