SECTION I · THE BRIEF
Brief #37782Updated 21 AUG 2026LONDON, ENGLAND, GBYcY COMBINATOR
Employbl Company Profile

Product Engineer

Cosine - Your AI Co-developer Ask complex coding questions, get explanations about features and plan new code just by asking our AI in plain English TLDR: Cosine is an AI knowledge engine that understands your codebase…

Location
London, England, GB
Company size
5–10
Posted
Today
Via
Yc
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Product Engineer · Cosine

View company profile
Job title
Product Engineer
Job location
London, England, GB
Job description
**Join Our Team\ At Cosine, we're pioneering the integration of human reasoning into artificial\ intelligence. As a member of our team, you'll be at the forefront of cutting-edge\ technology, working to shape the future of AI with our groundbreaking synthetic data\ generation and RFT techniques.** \ **Why Work With Us?**\ • Be part of a trailblazing company leading innovation in AI.\ • Work alongside a dedicated team of experts passionate about AI and technology.\ • Engage in challenging and rewarding work that makes a real impact on the\ advancement of AI. \ **Responsibilities**\ On this team you will build end-user products (developer workflow tools) that use\ Cosine's LLM and AI tech in order to augment developers’ capabilities for our users.\ We're building tools for ourselves. We are our own customer as engineers so you should\ be obsessed about the developer experience. * **Skills & Experience** * Experience building reactive applications (React, Vue, Rails, etc) that work\ across multiple platforms and that are highly interactive * Experience with NextJS and typescript * Comfortable with back-end development * Design back-end APIs * Expose and use rest endpoints * Experience with developer experience tools * Worked on CI/CD pipelines * Worked with containerization * Experience with testing code * Unit testing * Integration testing * Test performance optimization * Programming languages * Experience in either React, Vue, Typescript (we're open to people from\ other languages) * Knowledge of Node.js, Python or Go is a plus **Other relevant tools/experience** * DevOps: Git, AWS, Docker, PNPM, GitHub Actions * Monitoring and alerting (Grafana, Axiom) * Experience with feature flagging mechanisms (Posthog) \ **Requirements**\ • Minimum of 4 years of professional experience in software engineering. (Looking\ for mid to senior level candidates)\ • Proven expertise and expertise in the programming language of your choice.\ • Familiarity with AI technologies such as OpenAI, ChatGPT, Anthropic, ASTs,\ Github, Knowledge Graphs, Retrieval Augmented Generation, and Fine Tuning.\ • Strong problem-solving skills and the ability to work e\]ectively in a collaborative\ team environment.\ • Excellent communication and interpersonal skills.
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Cosine headquarters

San Francisco, CA

Company size

510 employees

Founded

2022

Total raised

$3,534,426

View company profile ↗

Funding rounds

  • Series Unknown$534.4K
  • Seed$2.5M
  • Pre Seed$500K