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Member of Technical Staff - Generalist

Trajectory · San Francisco, California

Location
San Francisco, California, United States
Employment
Full time
Level
Staff
Posted
7 May

About this role

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.

As published by Trajectory. Applications are handled on their site.

Skills this posting mentions

Agent SystemsFull Stack DevelopmentObservability

About Trajectory

Research lab and product company building the platform for continual learning.

All 6 openings at Trajectory

One click, then it is written

Apply to Trajectory with a resume written for this role.

Queue Member of Technical Staff - Generalist and I read the posting, rewrite your resume against it, draft the cover letter, and score the fit. Then you press send, or press one button and I fill in Trajectory’s form for you.

  1. 01Drop your resume

    A PDF or a LinkedIn URL. About a minute, once.

  2. 02I rank the openings

    Every weekday morning, the live catalog scored against your history. Up to 20 worth your time, not two hundred links.

  3. 03Each one is written up

    Resume rewritten for the posting, a cover letter, a fit score. Press send, or let me fill in the form.

  • 25 sent a week, free
  • No card
  • Nothing sent until you say so

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Put this to work

Paste your career in once. Every application after that is written for you.

Drop a resume or a LinkedIn URL. I rank the live openings against it, rewrite the resume and write a cover letter for the best of them, and fill in the employer's form when you press the button. You read, you decide what goes out.

  1. 01Drop your resume

    A PDF or a LinkedIn URL. About a minute, once.

  2. 02I rank the openings

    Every weekday morning, the live catalog scored against your history. Up to 20 worth your time, not two hundred links.

  3. 03Each one is written up

    Resume rewritten for the posting, a cover letter, a fit score. Press send, or let me fill in the form.

  • New matches ranked and written before you are up.
  • Every bullet stays inside what your history supports. Nothing invented.
  • Queued, submitted, interviewing, offer: one screen, not a spreadsheet.

500 free credits on sign-up. No card. Nothing is sent until you say so.

Listed from the job board Trajectory publishes. Refolk is not the employer and does not handle their hiring. Applications go to Trajectory directly.