Senior Backend Engineer

About this opportunity

This role is being recruited by Calyptus on behalf of one of our clients.

Calyptus is a specialist recruitment partner helping startups and high-growth technology companies hire across engineering, product and design.

What to expect

• We’ll review your application and, if your experience is a strong match, one of our team will be in touch
• We’ll support you throughout the interview process and keep you updated at each stage
• If this particular role isn’t the right fit, we may consider you for other relevant opportunities with our clients

We are looking for a Senior Backend Engineer with 5-15 years of experience to join our engineering team and build the production infrastructure powering our agentic AI capabilities. You'll be a strong individual contributor who loves shipping real features used by real people, in this case, 300+ leading VC and PE firms discovering insights in private markets. We need someone who is killer in Python, has deep experience building and deploying APIs at scale, and is excited about leveraging AI in their work. This is a rare opportunity to join a small, fast-moving team at an inflection point where your backend expertise will directly shape the next generation of AI-powered investment tools.

What will you be doing?

• Building and shipping production-grade backend services and APIs using Python and FastAPI that power our AI features
• Developing the infrastructure and orchestration layer for agentic AI capabilities within the product
• Working closely with databases (Postgres, ClickHouse) to enable intelligent data retrieval and AI-driven analysis
• Mentoring teammates and contributing to engineering best practices as the team scales from ~7 to 30+ people

Tech stack

Python, FastAPI, PostgreSQL, ClickHouse, SQL, LLMs (OpenAI, Anthropic), Embeddings / Vector DBs, AI coding tools (Cursor, Claude)

Genuine opportunities

Every role advertised by Calyptus is a live position we’re actively recruiting for. Some clients prefer to remain confidential during the early stages of the hiring process. When that’s the case, certain company details may be shared later in the process.

Why work with Calyptus?

• Access opportunities with ambitious startups and high-growth technology companies
• Direct support from experienced specialist recruiters
• Honest feedback and clear communication throughout the hiring process
• Long-term career support, not just a single job application

We look forward to hearing from you.