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Founding Engineer (AI Startup) (449A84C)

Referment· London, England, United KingdomEquity
Posted 21 Sept 2026 · Added 21 Sept 2026, 16:57
RefermentRecruitment agencyfounded 2016
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Free Tailor for ATS: 10/10 runs left

Some engineers enjoy writing code. Others can't stop building.

If you've been programming since you were a teenager, spend your evenings experimenting with new technology, and get genuine satisfaction from shipping products, this role was written for you.

Referment is partnering with a venture-backed AI startup looking for one exceptional engineer to help build the next generation of AI-powered cybersecurity products.

You'll work directly with the founders and own features from customer problem through to production.

You'll enjoy this role if you...

Love building more than talking about building

Prefer shipping software over writing documentation

Can move between backend, frontend and infrastructure without thinking twice

Get excited by hard engineering challenges like building compilers, DSLs, or internal developer tools

Use AI every day, but don't rely on it to think for you

Enjoy solving messy customer problems instead of perfectly defined tickets

What You'll Be Building

Rather than owning a small corner of a huge codebase, you'll own products end-to-end

You'll design complex backend architecture and systems.

Ship React interfaces.

Build internal developer tools and agentic consoles.

Improve databases and handle systems programming.

Debug production and deploy continuously.

Help shape both the product and the engineering culture.

What We're Looking For

Deep technical focus on hard engineering and complex backend architecture

Strong Python backend fundamentals with high-level application of tools like FastAPI, Django, or Flask

Senior-level technical sophistication and the ability to move beyond routine maintenance tasks

Verifiable track record of technical contributions and honest project claims (e.g. active GitHub or OSS presence)

React experience or willingness to work across the frontend

Startup mentality with genuine product ownership

Around 3-6 years' experience with a focus on engineering depth

Extra points for experience with:

Founding or leadership roles (e.g. Co-Founder or CTO)

Building internal developer tools, DSLs, or compilers

Multi-language proficiency (e.g. Go, C, or Rust)

Cybersecurity

Workflow orchestration (Prefect, Airflow)

High-growth SaaS

This probably isn't for you if...

Your focus is primarily on product management or innovation titles rather than hands-on engineering

You consider routine infrastructure maintenance to be your core focus area

You need detailed specs before starting work

You only enjoy one part of the stack

You avoid production responsibility

You're looking for a comfortable corporate engineering role

You're currently splitting your attention with another startup

Why join?

Competitive salary

Meaningful equity

One of the first engineering hires

Direct access to the founders

Huge ownership from day one

Build products that customers actually use

#Referment