Senior Software Engineer (London)

Overview

• Start date: ASAP
• Reporting to: Staff or Senior engineer in one of our product squads.
• Visa sponsorship: Unfortunately, we are unable to offer visa sponsorship for this role. Applicants should have the right to work in the UK at the time of application.
• Background checks: Due to the nature of the work we do with global governments and partners, all employees need to pass background checks, verifying your identity, education (if relevant), work history, sanctions, criminal record, adverse financial history and right to work.
• You can expect to hear from us, no matter the outcome, by: 15th August 2025
• Salary expectations: We aim for transparency on salary bands. If our range is misaligned with your expectations, wed welcome an open conversation as early as possible.

Role

Apoliticals platform helps 250k+ public servants share knowledge and solve problems faster. Our engineering team ships a modern monorepo (Nx, PNPM) using React/Next.js, Node/NestJS, PostgreSQL and Kubernetes on GCP. We are expanding the squad with a senior engineer who can deliver robust product features and help us responsibly weave AI (LLMs, RAG) into the user experiencealongside peers who already experiment with Pinecone, LangChain and VertexAI.

As a senior fullstack engineer you will design, build and operate userfacing features endtoendUI components, APIs, data models and infrawhile mentoring teammates and shaping architecture. Roughly 7080% of your time will focus on core product work; the remaining capacity goes to advancing AIenabled features (vector search, content recommendations, conversational agents) in partnership with product and data science.

Success is measured by your ability to:

• Ship reliable, maintainable code across the stack that meets performance & accessibility targets.
• Increase squad velocity through sound architectural decisions, clear documentation and code reviews.
• Coach midlevel engineers and foster a culture of high standards and continuous learning.
• Deliver incremental AI capabilities that demonstrably improve user outcomes and are costeffective.

Tasks and remit:

• Feature delivery Build and test new product features fronttoback using React/Next.js, NestJS and PostgreSQL.
• Architecture stewardship Drive RFCs, enforce TypeScript standards, improve CI/CD and observability.
• AI integration (as needed) Prototype and productionise LLM/RAG components (VertexAI, Pinecone, LangChain) when they add clear value; own evaluation metrics and cost monitoring.
• Quality & performance Champion automated testing, accessibility and webperformance budgets.
• Mentorship & collaboration Pair program, run knowledgeshare sessions and provide thoughtful reviews.This role is exciting if youre eager to grow technically and professionally in a supportive, pragmatic team. Youll be empowered to own code, propose improvements and understand how your work impacts our users.

You will be:

• Writing TypeScript dailyUI, serverside APIs, tests and DevOps scripts.
• Designing data models, API contracts and caching strategies.
• Investigating user issues, profiling performance and automating fixes.
• Exploring AI techniques (prompt design, retrieval strategies) as part of feature work.

You wont be:

• Peoplemanaging (though youll influence broadly).
• Working exclusively on AI; most work is core product engineering.

Role expectations

Timelines may vary depending on individual onboarding and support needs, but we expect most team members to achieve the following milestones:

Within one month, you will

• Ship a nontrivial PR to production.
• Complete onboarding to monorepo, CI and infra.
• Pair with peers to understand existing AI components.

Within three months, you will

• Lead delivery of a fullstack feature from spec to prod.
• Introduce an architecture improvement (e.g. caching, DX, test coverage).
• Contribute to an AI experiment or refactor an existing RAG flow for reliability.

Within six months, you will

• Act as goto engineer for a product surface (e.g. search, notifications, AI helpers).
• Mentor at least one other engineers.
• Write an RFC proposal balancing core product and AI enhancements, with metrics.

About you

This is a great fit if you

• Have 6+years building production web apps (React + Node) with strong testing and TypeScript skills.
• Enjoy endtoend ownershipUI polish, API design, data modelling and deployment.
• Are curious about LLMs/agentic workflows and have tinkered or shipped small features already.
• Value pragmatic solutions, measurable impact and clean, maintainable code.
• Are comfortable with GDPR, ISO27001 and privacybydesign principles.

Let us know if you have

• Experience integrating LLM services (VertexAI, OpenAI) and vector DBs (Pinecone).
• Implemented feature flagging & A/B experimentation.
• Worked on accessibility, localisation or performancecritical projects.
• Background in information retrieval or search relevance.

This likely wont be the right role if you

• Need extensive structure or a narrow, fixed role.
• Are not flexible with regards to working on frontend vs. backend.
• Are looking for big-tech company, fixed processes, or large teams.
• Have a minimal interest in coding to high production standards.
• Minimal interest in team collaboration and knowledge sharing.
• Prefer novelty over practicality in technical decision making.

Dont meet every single expectation? Studies have shown that women and people of colour are less likely to apply to jobs unless they meet every single qualification. Apolitical is dedicated to building a diverse and inclusive workplace, so if youre excited about this role but your past experience doesnt align perfectly with every qualification in the job description, we encourage you to apply anyways. You may be just the right candidate for this or other roles.