Happl Logo

Happl

Backend Engineer

Reposted 25 Days Ago
Be an Early Applicant
Hybrid
London, Greater London, England, GBR
Mid level
Hybrid
London, Greater London, England, GBR
Mid level
Build and scale backend services for a global AI-first benefits platform. Design architecture, own core services (payments, allowances, reporting), model data, improve reliability/security/observability, automate workflows, integrate third-party services, collaborate across teams, and write well-tested production code.
The summary above was generated by AI

We’re building the next generation of employee benefits infrastructure.

At Happl, we help global teams design, manage, and scale benefits that actually work for their people by using AI, across flex allowances, benefits, insurance, recognition, and wellbeing, all in one intelligent platform.

Happl is backed by leading investors such as YCombinator, 6Degrees Capital, and more, known for backing leading companies such as Deel, Rippling, Airbnb, Coinbase, Dropbox, and most recently was awarded a place in the UK’s top 100 startups for 2026.

About the role

As a Backend Engineer at Happl, your mission is to build the systems that power a global, AI-first benefits platform.

You’ll design, build, and scale backend services that are reliable, secure, and performant, enabling our product teams to move fast while supporting complex real-world use cases across payroll, finance, and employee benefits.

This role is for someone who enjoys ownership, thrives in fast-moving environments, and wants to build foundational systems that directly impact how companies support their people.

This is a hybrid role based in London, with an expectation of working from the office at least 2–3 days per week.

What you’ll be doing

This role sits within our Engineering team and works closely with Product, Frontend, Data, and Customer teams across the full development lifecycle.

You’ll help shape how we build and scale our backend by focusing on:

  • Designing and scaling the backend architecture powering a global, AI-first platform

  • Building and owning core services across benefits, allowances, payments, and reporting

  • Developing scalable data models and ensure integrity across systems

  • Improving platform reliability, performance, security, and observability

  • Automating workflows and Go Rules to streamline complex operations

  • Collaborating closely with product and frontend teams to ship end-to-end features

  • Writing clean, well-tested, production-ready code

  • Using AI tools to accelerate development and iteration

  • Contribute to architecture, technical decisions, and engineering standards

You’ll play a key role in ensuring Happl’s backend scales as our customer base, features, and global footprint grow.

What we’re looking for

  • 3+ years experience as a Backend or Software Engineer

  • Strong experience with modern backend languages and frameworks (must have a working ability in Golang and Typescript)

  • Experience designing and consuming APIs (REST, event-driven systems)

  • Solid understanding of databases (SQL / PostgreSQL) and data modelling

  • Experience building and scaling production systems

  • Familiarity with cloud infrastructure and CI/CD workflows

  • Comfortable working with integrations and third-party services

  • Experience using AI tools (e.g. ChatGPT, Claude) as part of your workflow

  • Clear communicator who works well with both technical and non-technical stakeholders

  • Proactive, detail-oriented, and comfortable taking ownership

If you don’t meet every requirement but feel this role fits your trajectory, we’d still love to hear from you.

Why join Happl

  • Help shape the future of employee benefits

  • Competitive base salary and commission

  • Meaningful equity in an early stage growing business

  • Flexible hybrid working from day one

  • Access to your own Happl benefits platform

  • Optional enrolment in Private Health Insurance

  • Optional enrolment in Dental insurance, including family cover

  • A flexible Wellbeing budget to spend on whatever wellbeing means to you

  • Learning & Development (L&D) allowance

  • Pension scheme from day one

  • Rapid career progression in a scaling engineering team


About the Interview

  • Call 1: 20-min Intro call with Ben (COO & CoS)

  • Call 2: 30-min deep dive with Lee (Head of Engineering)

  • Short Task

  • Call 3: 30-min deep dive with Ben T (CEO & Founder)

Additional Details

Location: London, Holborn
Team: Engineering
Working arrangement: Hybrid (3+ Days in Office)

#BS-L1

Happl London, England Office

London, England, United Kingdom

Similar Jobs

Yesterday
Hybrid
Entry level
Entry level
Digital Media • Gaming • Software • Esports • Automation
Build and maintain the backend platform powering the FollowScores football app. Develop scalable Golang microservices, REST APIs, and WebSocket systems using Redis and GCP to deliver high-performance real-time updates. Integrate third-party systems, meet business requirements, and create robust, highly available solutions for millions of users across mobile platforms.
Top Skills: .NetGoGoogle Cloud Platform (Gcp)MicroservicesRedisRest ApisWebsockets
Yesterday
Hybrid
Entry level
Entry level
Digital Media • Gaming • Software • Esports • Automation
Build and scale the backend platform for the FollowScores football app. Develop high-performance Golang microservices, WebSocket and REST API systems using Redis and GCP. Deliver scalable, maintainable, highly available software for millions of users, integrate third-party systems, meet business requirements, and collaborate within a technically focused team.
Top Skills: .NetGoGoogle Cloud Platform (Gcp)MicroservicesRedisRest ApisWebsockets
6 Days Ago
Easy Apply
Hybrid
London, Greater London, England, GBR
Easy Apply
Senior level
Senior level
Fintech • Information Technology • Payments • Productivity • Software • Travel • Automation
Design and develop scalable backend systems for a global expense management platform supporting commerce, payments, issuing, ledgers, automated policies, administrative controls, and accounting integrations. Own features end to end from architecture and implementation through deployment, monitoring, troubleshooting, and operational support. Collaborate with engineering, product, design, and business teams while promoting high standards for scalability, testing, documentation, reliability, and code quality.
Top Skills: Ai ModelsApi DesignAWSDistributed SystemsJavaJvmMicroservicesSpring Boot

What you need to know about the London Tech Scene

London isn't just a hub for established businesses; it's also a nursery for innovation. Boasting one of the most recognized fintech ecosystems in Europe, attracting billions in investments each year, London's success has made it a go-to destination for startups looking to make their mark. Top U.K. companies like Hoptin, Moneybox and Marshmallow have already made the city their base — yet fintech is just the beginning. From healthtech to renewable energy to cybersecurity and beyond, the city's startups are breaking new ground across a range of industries.

Sign up now Access later

Create Free Account

Please log in or sign up to report this job.

Create Free Account