Product Engineer
Product Engineer at Cosine — London, England, GB
- Company: Cosine
- Location: London, England, GB
- Employment type: FULL_TIME
- Salary: USD 70000–90000 / year
- Posted: 2026-07-17
About this role
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.