As the highest individual contributor, you will drive technical excellence across Definely's full-stack AI platform. You’ll architect scalable systems for processing complex legal documents, lead high-level design discussions, and maintain a hands-on presence in the codebase. Your leadership will raise engineering standards while mentoring the team through critical architectural migrations and platform modernization.
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Staff Software Engineer at Definely
Definely is seeking a Staff Software Engineer to join as the highest individual contributor on their core engineering team. If you are a full-stack expert comfortable architecting scalable document-processing systems and influencing technical direction across Python, TypeScript, and C# stacks, this is a rare opportunity to lead at a category-defining company. The role offers up to £130k plus equity and a hybrid London working model.
About this role
Role overview
About the company
Definely is an AI-powered LegalTech company that provides a suite of tools to help corporate and private practice lawyers draft, review, and manage complex contracts more efficiently, primarily within Microsoft Word. Its products streamline the creation, editing, and quality-checking of legal documents by keeping lawyers in their natural workflow while enabling fast navigation across definitions, references, and clauses. Originally designed to make legal documents more accessible for visually impaired professionals, Definely has evolved into a broader drafting, reviewing, and knowledge platform used by in-house legal teams and law firms globally. The product suite includes features such as contextual editing, clause insertion and reuse via a knowledge repository (Vault), and AI-assisted drafting and review (Enhance and Draft). Definely aims to reduce review time, standardize document quality, mitigate legal and operational risk, and simplify how legal teams understand and work with complex information. The company is a fast-growing, Series B–stage scale-up headquartered in the UK and focuses on transforming the global legal services market through AI-driven document workflows.
What you'll do
What you will do
- Architect and build end-to-end systems, from React-based frontends to high-performance data pipelines and backend services in Python and C#.
- Lead technical design discussions and build consensus on complex architectural decisions to ensure system reliability at scale.
- Uphold engineering standards through rigorous code reviews, mentoring junior engineers, and proactively addressing architectural technical debt.
Who you are
Who this is a fit for
- Proven experience as a senior or staff IC with deep full-stack architectural expertise and fluency in Python, TypeScript, or C#/.NET.
- Strong background building and operating distributed systems or data-intensive services capable of processing large volumes of complex data.
- Excellent communication skills with a track record of influencing technical direction and mentoring engineering teams without needing a management title.
Why this role
Why this role is remarkable
- Join as the highest IC level on the core engineering team, directly shaping the architectural future of a category-defining AI legal platform.
- Work with a high-growth Series B scale-up backed by elite investors including Microsoft, Google, and Octopus Ventures.
- Solve deep technical challenges involving high-throughput document processing, vector databases, and real-time AI verification for global enterprises like Barclays.
Jack & Jill
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.
Meet Jack
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.
How does this work?
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 it’s a match and the company wants to meet you, they’ll make the intro. In the meantime, if you’d like, Jack will send you excellent alternatives.