Senior Backend Engineer — AI-Powered FinTech APIs (Remote)

Ersilia; Greater London; Hybrid; GBP 90,000 - 130,000; Full time

Job summary

Ersilia in London is seeking a Senior Backend Engineer to own the production Python backends and APIs that power our AI features used by professional investors.

The role covers building the orchestration layer for agentic AI, serving data via PostgreSQL and ClickHouse at scale, and shipping features from idea to production in a single sprint. You will mentor teammates and help shape engineering standards as the team grows from seven to over thirty, collaborating closely with the founders.

Qualifications

• 5–15 years backend engineering experience in Python in production.
• Owns APIs/services used by real customers.
• Experience shipping AI/LLM features to production.
• Strong SQL and PostgreSQL or equivalent.

Responsibilities

• Build and ship production Python backends and APIs powering AI features.
• Own orchestration layer for agentic AI capabilities.
• Work with PostgreSQL and ClickHouse for fast data access.
• Deliver features end-to-end within sprints.
• Mentor teammates and help set engineering standards.
• Shape architecture and tooling through close founder collaboration.
• Collaborate with founders on what to build next.

Skills

Python

API design

SQL

API ownership

AI features shipping

Startup experience

Mentoring

Data platforms

Team collaboration

Production readiness

Tools

PostgreSQL

ClickHouse

Job description

Ersilia in London is seeking a Senior Backend Engineer to own the production Python backends and APIs that power our AI features used by professional investors.

The role covers building the orchestration layer for agentic AI, serving data via PostgreSQL and ClickHouse at scale, and shipping features from idea to production in a single sprint. You will mentor teammates and help shape engineering standards as the team grows from seven to over thirty, collaborating closely with the founders.