As a Staff Software Engineer at UnlikelyAI, you will be the lead individual contributor shaping a novel neurosymbolic platform. You’ll bridge the gap between probabilistic machine learning and deterministic computing, architecting public APIs and document pipelines that enable enterprises to deploy reliable, explainable AI at scale for high-stakes financial and compliance use cases.
Staff Software Engineer at UnlikelyAI
You will lead the technical evolution of a unique neurosymbolic platform that combines LLMs with deterministic reasoning for tier-1 banks and accountancy firms. If you have deep Python expertise and a passion for building reliable AI systems that solve the accuracy problem in regulated industries, this role offers £130k-£150k, meaningful equity, and the chance to architect a global public API from the ground up.
Want to apply for this role?
Jack finds you jobs at companies like UnlikelyAI. Talk to Jack to get considered for roles that fit what you're great at.
Location
London, United Kingdom
Compensation
£130k-£150k + Equity
Company
UnlikelyAI
Role overview
Software
UnlikelyAI is a London-based technology company pioneering neurosymbolic AI, which integrates the strengths of machine learning with symbolic computing to deliver reliable, explainable, and trustworthy artificial intelligence systems. Their platform emphasizes controllable, auditable, and hallucination-free AI solutions for decision-making, especially tailored for enterprises in highly regulated industries where transparency and trust are critical. Founded by William Tunstall-Pedoe, their technology bridges probabilistic machine learning and deterministic symbolic systems—aiming to eliminate common AI risks such as hallucinations, bias, and black-box decision-making. Unlikely AI’s Universal Language (UL) underpins their solutions, enabling robust applications for large language models and generative AI. The company focuses on building AI products capable of previously impossible tasks, with a strong commitment to responsible development and real-world usability.
What you will do
- Architect and build the foundational public API, making critical decisions on scalability, versioning, and developer experience that will shape the platform for years.
- Design and implement complex document ingestion pipelines and symbolic reasoning engines capable of handling diverse regulatory data formats with deterministic precision.
- Drive cross-cutting technical initiatives and raise the engineering bar by mentoring talent, conducting deep system design reviews, and establishing production-quality standards.
Who this is a fit for
- Deep expertise in Python and a proven track record of architecting large-scale, production-grade systems within complex collaborative codebases and monorepos.
- Extensive experience with complex algorithms, data structures, and cloud infrastructure (AWS/Terraform) to support non-trivial algorithmic problems at enterprise scale.
- Demonstrated technical leadership through influence, having shaped the architectural trajectory of products or platforms without necessarily managing direct reports.
===
Why this role is remarkable
- Work at the frontier of AI alongside a world-class team from Google, Amazon, and Imperial College, founded by the visionary creator of Alexa.
- Solve the critical “reliability problem” in AI by building a unique neurosymbolic engine that combines the power of LLMs with deterministic, symbolic reasoning.
- Lead the transition from bespoke enterprise engagements to a scalable global platform, owning the architecture of the company’s first public API and core infrastructure.
How Jack & Jill work together
I get to know what you’re great at, then find roles you’d never find yourself.Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
I recruit from Jack’s network and make the intro when I spot a great match.And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
Jack gets to know what you're great at and what you want next, then searches 15 million jobs daily and helps you discover roles at companies like this.
Meet Jack
What happens next?
Jack’s an AI agent for job searching and career coaching. He works for you.
Jill is the AI recruiter working for the company. She recruits from Jack’s network.
If your profile’s a match and UnlikelyAI wants to meet, Jill will make the intro. In the meantime, Jack will send you excellent alternatives.