Job Description

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

You will own the SDK, API surfaces, and integration infrastructure 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.

Required Qualifications

Strong full-stack or backend engineering experience

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

Experience building developer-facing products or SDKs

Experience with data pipelines, telemetry systems, or event infrastructure

Ability to move quickly in a zero-to-one environment

Preferred

Experience building observability, tracing, or monitoring systems

Experience at early-stage developer tooling startups

Strong product instincts and ability to work directly with customers

Experience owning SDK design and developer ergonomics

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.