Backend Engineer - Phone Scam Disruption

UK (London, Manchester, Bath)

Netcraft is the global leader in cybercrime detection and disruption. We’re a trusted partner for three of the four largest companies in the world and many large governments. We've blocked over 225 million cyber-attacks to date, and we take down around 33% of the world's phishing attacks.

Our purpose and passion are focused on just one thing: protecting the world from cybercrime.

That passion shapes how we work, too. We’re proud of our talented team and the value each person brings, and we’ve built a workplace where people feel supported and inspired. From strong benefits and wellness programs to meaningful collaboration and team connection.

We’re searching for a Backend Engineer to join our growing engineering team. Based in either London, Manchester, or Bath, you’ll report to one of our Engineering Managers and work primarily on the backend of our broad range of cybercrime detection and disruption services. The service you’ll spend most of your time on is our phone scam disruption product.

Criminals impersonate trusted brands like banks, retailers and delivery firms over calls and texts to defraud their customers. Our product finds the phone numbers behind these scams and gets them disabled  report them to the mobile carriers and toll‑free providers we work with directly.

The department you’ll be joining is Specialised Disruption, where you’ll often work on the newer and more novel parts of our platform, but you’ll also pick up work across the department’s other products, especially as new ones emerge and existing ones evolve. The department is fast‑moving and involves working on products that might not have found perfect product‑market fit yet.

This role is a mix of maintenance and feature work. You’ll design and build new features and services as the product grows, and take ownership of the systems already in production, caring as much about their reliability, performance, and stability as about what you ship next.

The phone scam product is primarily Go, alongside some legacy Perl systems that you’ll help maintain and gradually modernise, and an internal Type Script UI. It would suit an engineer who’s happy working across that whole span, with the main focus on the backend.

You’ll sometimes help the commercial team work out where a product fits, weighing up which customers it suits and what’s realistic to build. That can mean jumping into a proof of concept yourself, making sure the product works well and improving it where it falls short.

• Designing and building features and improvements to our products, while taking non‑functional requirements like performance, reliability, and security into account.
• Maintaining and modernising existing services, including some legacy Perl, ensuring stability, maintainability, and operational reliability.
• Testing and documenting your work to a high standard with strong attention to detail.
• Taking responsibility for system maintenance, operational stability, and incident prevention.
• Responding to issues with a sense of urgency and ownership, identifying root causes and implementing long‑term fixes.
• Identifying scaling bottlenecks and resolving them, while being conscious of running costs.
• Collaborating with other engineering teams to ensure services you own are well‑integrated with their services.
• Working with cross‑functional stakeholders to help propose, design and implement solutions to meet business needs.
• Working independently and proactively, identifying opportunities to improve systems and processes over time.

• Experience developing and maintaining production backend systems, ideally in Go or a similar backend language.
• Experience in a domain relevant to phone scams, such as telecoms, phone or messaging systems, or fraud and anti‑abuse. You don’t need to have worked at a telco, but you should bring relevant experience from an adjacent area.
• The ability to work independently and take ownership of services and systems.
• Strong attention to detail, particularly when working with production systems.
• A proactive mindset when addressing operational…