Senior Software Engineer in London

We’re Tails.com, a dog food subscription company with a big difference. We create truly tailored food for each and every dog we serve. We start by asking people a few simple questions about their dog. Then we use that information to create their dog’s unique Tails.com recipe – so their dog gets exactly the nutrition they need, in the taste they love, delivered to their door every month.

We are a fast-growing scale‑up company, transitioning from our start‑up roots and entering an exciting phase of rapid growth. As we evolve, we are focused on building a modern, scalable, and secure architecture that will support our ambitious plans for the future.

Software Engineering at Tails.com: We’re a 40+ strong, diverse team of software, cloud infrastructure and quality assurance engineers distributed across 6 squads, working across the customer‑facing parts of tails.com as well as factory automation and fulfilment of tens of thousands of orders per day – in 9 countries.

The role: As a Senior Software Engineer, you’ll be a key contributor within a cross‑functional squad, delivering high‑quality, scalable software that drives business impact. You’ll combine strong technical skills with the ability to influence beyond your immediate team, mentor others, and help shape how we build software at Tails.com.

Your Responsibilities:

• Technical delivery & quality: Design, implement, and maintain scalable and reliable systems within your squad, writing expert‑level code in the languages we support in our platform. Contribute to architectural discussions, ensuring designs align with agreed principles from Leads and Principals. Write clean, maintainable, and testable code, and review code from peers to share knowledge and improve quality. Help ensure the squad’s systems meet agreed performance, reliability, and security standards.
• Collaboration & delivery: Work closely with your squad’s Lead Software Engineer, Product Manager, and Designer to shape and deliver solutions. Collaborate with Principal Engineers on applying architecture patterns and technical standards. Raise risks or issues early, and contribute to resolving them within the squad.
• Continuous improvement: Suggest ways to improve how the squad delivers software, based on feedback and retrospectives. Apply best practices in testing, CI/CD, observability, and security in your work.
• Mentorship & growth: Mentor and pair with engineers in your squad to help them grow their technical skills. Share your knowledge through documentation, demos, and informal learning sessions.
• Commercial awareness: Understand how your work supports the squad’s goals and contributes to customer and business outcomes.

About You: You’re an experienced software engineer with a track record of delivering high‑quality systems in a fast‑paced, product‑led environment. You design and build scalable, secure, and maintainable solutions, with a mindset for future requirements. You collaborate effectively within your squad and share knowledge or technical solutions that benefit other teams. You contribute to architectural design within your squad, defining SLAs where relevant and proactively improving system reliability. You challenge and adapt delivery processes when you see opportunities to improve outcomes, informed by team feedback. You mentor engineers within your squad to support their technical growth and encourage them to participate in wider engineering discussions. You anticipate when others need information, communicating proactively and ensuring clarity across the squad and with stakeholders. You understand how your work supports company values and commercial goals, and you’re comfortable questioning approaches that don’t align. You’re motivated by the opportunity to refine your skills, grow your influence, and contribute to a high‑performing engineering culture in a growing scale‑up.

The Skills You’ll Bring: Python 3 (plus Flask, Django or any other framework), with web experience. At least one SQL dialect. Running Docker locally and in production. Experience with Rust, Kubernetes, event systems (especially Kafka), scaling and running high‑traffic software on AWS or GCP are nice to have. Experience working with fulfilment systems is nice to have.

What’s in it for you? Competitive salary, reviewed annually. Annual bonus, based on company performance. Flexible core hours, giving you true work‑life balance. Hybrid role to ensure this role works for you. 25 days of holiday.