Software Engineer

About the role Compensation: £70k–£120k salary (based on years of experience) + equity, based in London, UK. We are hiring a Software Engineer to join Squid as one of our first engineers. You'll work closely with the founders and early engineering team to build production software for grid operators. This is a broad engineering role spanning backend systems, frontend products, data-intensive applications, cloud infrastructure and applied AI. You'll help turn complex engineering workflows into reliable, intuitive software used by planners, operators and engineers working on critical infrastructure. This is a high-ownership role based in our central London office. You'll have the opportunity to shape the product, technical architecture and engineering culture from an early stage. What you'll do Build and ship production software across backend services, frontend applications and cloud infrastructure. Design APIs, data models and product interfaces for complex, data-heavy workflows. Develop tools for loading, validating, comparing, visualising and explaining large technical datasets. Build reliable systems for versioning, collaboration, approvals and auditability. Integrate AI models and agents into practical, human-in-the-loop product workflows. Create benchmarks and evaluation systems for testing AI on real customer tasks. Improve system performance, reliability, security and developer experience. Work directly with customers to understand problems, test solutions and iterate quickly. Use modern AI development tools to prototype, test and ship software. What we're looking for You don't need to meet every requirement. We're looking for strong, product-minded software engineers who are comfortable working across a broad technical surface area. You may be a strong fit if you have: Professional software engineering experience building and maintaining production systems. Experience with technologies such as Python, TypeScript, React, Postgres, APIs, cloud infrastructure or data pipelines. Experience working with relational databases, columnar data formats and object storage. Experience working across multiple parts of a software stack rather than within one narrow specialism. Strong product judgement and the ability to turn ambiguous, real-world problems into practical software. Experience designing reliable systems for complex or data-intensive workflows. An interest in applied AI, model evaluation, agent systems and AI-assisted software development. The ability to communicate clearly and work directly with technical customers. High ownership, curiosity and a willingness to learn quickly. Experience with developer tools, data visualisation, geospatial products, collaborative software, workflow engines, technical computing or regulated industries is valuable, but not required. About Squid AI and data centres are booming, electrification is accelerating, and trillions in generation, storage and connection projects are queued — but the real bottleneck is the grid. Grid planning and operations are becoming a national-scale systems problem: complex network models, messy legacy data, strict governance, overloaded teams and high-stakes decisions affecting real infrastructure. Squid is building the agentic modelling platform for power grids: a versioned, auditable source of truth where network models, data, changes, assumptions and decisions can be tracked — and where humans and AI agents can safely work together. We unify legacy planning models, operational data and grid workflows into software that helps teams run checks, compare models, explain changes, validate assumptions and move faster without losing engineering rigour. Based in London, Squid is backed by Y Combinator and other leading investors and works with organisations including National Grid and Northern Powergrid . 🦑 Visa: Will sponsor.