Senior / Tech Lead / Staff / Principal Software Engineers, AI Email App
Levels: Senior / Tech Lead / Staff / Principal
Location: Remote first company
** These roles will be a 0-1 building a global AI product as part of the Founding team and will consist of a generous Salary, Bonus and Equity package**
About the Company
Over 5 billion people use basic applications today, email, notes, tasks and calendar, and none of them are truly AI native. Our client's mission is to build proactive applications for anyone in the world, including people who are not used to complex prompting. They have just raised $100 million, backed by a globally recognised organisation and are bringing intelligence to conversations, errands, organising and workflows, with minimal to no prompting required.
The first product reimagines email, moving users from writing and reading email to reviewing and approving AI completed work, with the ambition of cutting the average person's daily email time from around 4 hours to around 30 minutes.
About the Role
Our client is hiring Software Engineers for their AI Email App at Senior, Tech Lead, Staff and Principal levels, with seniority and scope matched to experience. You will help build the engineering layer that turns AI capability into a reliable, real world product, shaping architecture across backend services, APIs and client applications (mobile and desktop). At Staff and Principal level, this extends to leading a small team of senior engineers and owning critical architectural decisions as the system scales.
This is a hands on role at every level. You stay close to the code, contribute to key technical decisions, and help ensure the system remains fast, reliable and coherent as it grows.
Tech stack includes:
- Frontend: TypeScript, React.js/Next.js, HTML/CSS, Node.js, WebSockets/streaming APIs, REST/GraphQL
- Desktop: JavaScript/TypeScript/Node.js, Electron, SQLite and IndexedDB for local storage, WebSockets/IPC
- Mobile (Android): Kotlin/Java, Coroutines and Flow, REST or gRPC, TensorFlow Lite for on device inference, MLKit
- Backend / AI systems: Python and Node.js, PyTorch/JAX, LLM APIs (OpenAI style, Anthropic, LLaMA, Qwen, other open source models), vLLM for inference serving, vector databases, SQL/NoSQL, Docker and Kubernetes
What You Will Own
- Application engineering, spanning strategy and hands on execution across backend, mobile and desktop
- Design of reliable systems for AI powered workflows, including state, orchestration, tool use, retries, fallbacks and failure handling
- The APIs and abstractions that connect AI systems to real world product experiences
- At Staff and Principal level: leading a small, senior engineering team and raising the technical bar through design reviews, code reviews and hands on mentorship
- Trade offs across latency, reliability, cost, security and user experience, with the scale of impact increasing by level
- Strong production foundations: observability, monitoring, testing and operational excellence
- Close partnership with ML leadership to turn model capabilities into robust, shippable product experiences
- Moving quickly while keeping the architecture simple, maintainable and ready to scale
What Our Client Is Looking For
- Experience in application or product engineering for complex systems, at a level consistent with Senior, Tech Lead, Staff or Principal seniority
- A strong, hands on background building and shipping backend systems used in production, ideally in Python or Node.js
- Experience building AI powered products or systems that integrate with modern ML or LLM capabilities, such as Anthropic or OpenAI style APIs
- Comfort working across backend and client platforms, such as React, TypeScript, Electron or Kotlin, with deep expertise in at least one
- Working knowledge of SQL and NoSQL data stores, and ideally vector databases for retrieval or persistent context
- Familiarity with Docker and Kubernetes, and how modern AI powered services are deployed and operated in production
- Strong technical judgement and the ability to make decisions with incomplete information
- A strong bias toward ownership, shipping and learning from real world usage
- High standards for code quality, reliability and engineering fundamentals
- For Tech Lead, Staff and Principal candidates: a track record of technical leadership, mentorship and raising the bar within an engineering team
Outcomes You Will Drive
- Production systems that are observable, monitored and stable under real world load
- Decisions that consistently balance speed, cost, reliability and user experience
- Features across backend, mobile and desktop that work smoothly and reliably
- Measurable improvement in latency and reliability over time
To be considered, please apply now with your latest CV .
