Senior Application Engineer

Senior Application Engineer Overview

This opportunity is with a fast-growing London-based SaaS startup that is building an AI-powered platform for commercial teams who need to manage and close complex deals. The company is looking for a product-minded engineer who cares deeply about the quality of the software they build, how it behaves in practice, and the value it creates for users.

What makes the role appealing

The environment is set up for genuine product engineering rather than narrow task execution. Engineers are expected to take ownership of features from beginning to end, work closely with product and design colleagues, and help shape solutions rather than simply implement handed-down requirements. The team moves quickly, learns from real user feedback, and can see the impact of its work in the product.

The culture is described as small, collaborative, energetic, and full of personality in a way that feels natural rather than forced. People typically spend around two to three days a week in the office because they want to, not because they are required to. The successful candidate will also work closely with a highly experienced and approachable Director of Engineering who values autonomy, trust, and building a team that people genuinely enjoy being part of.

There is also a strong focus on AI and automation. The business is actively investing in work such as bringing generative AI into product workflows, experimenting with language-model-based capabilities, and using AI to improve both the customer experience and internal processes.

Role focus

• Take full ownership of product features and see them through from concept to delivery.
• Partner directly with product and design to refine ideas and turn them into effective solutions.
• Contribute to a rapid iteration cycle where user feedback informs ongoing improvements.
• Help shape technical and product decisions by challenging ideas constructively and bringing your own perspective.
• Support the development of AI-enabled functionality across the platform.
• Work on generative AI integrations, LLM-based features, and retrieval-augmented generation style capabilities.
• Use automation and AI to improve both the product itself and the company’s internal workflows.
• Collaborate within a small, high-energy team where individual contributions have clear visibility and impact.

Technology environment

The stack includes Next.js, React, TypeScript, Node.js, AWS, and a modern API-driven architecture. The role suits someone who is comfortable working across the full product stack and who enjoys building in a contemporary web and cloud environment.

What they are looking for

• A senior engineer with a strong product mindset and a genuine interest in how software affects users.
• Someone who enjoys end-to-end ownership and working closely with cross-functional partners.
• Experience with the listed stack: Next.js, React, TypeScript, Node.js, and AWS.
• Familiarity with modern API-based systems.
• Interest in, or hands-on experience with, AI-driven product development, including generative AI, LLMs, and RAG-style approaches.
• A collaborative approach and the confidence to influence solutions through thoughtful challenge and discussion.
• Comfort in a fast-moving startup setting where priorities can change and iteration is frequent.
• Someone who wants to develop with the company over the long term.

Package and working arrangement

The position is permanent and offers a salary of £65,000 to £95,000 depending on experience. The role is based in Cambridge or London and follows a hybrid pattern, with most of the team choosing to spend two to three days a week in the office.

How to apply

Interested candidates can apply through the job listing using the application option provided on the page. The posting also includes a direct contact route through Avanti Recruitment for anyone who wants to get in touch about the role.

Degree Requirement: Not Specified

Visa Sponsorship Promising