Backend Engineer, UI Platform en Barcelona, España

Who we are 

About Stripe

Stripe is a financial infrastructure platform for businesses. Millions of companies—from the world’s largest enterprises to the most ambitious startups—use Stripe to accept payments, grow their revenue, and accelerate new business opportunities. Our mission is to increase the GDP of the internet, and we have a staggering amount of work ahead. That means you have an unprecedented opportunity to put the global economy within everyone’s reach while doing the most important work of your career.

About the team

The UI Platform team, known as Sail, builds the foundations behind Stripe’s Dashboard and many other user interfaces. Sail Services owns the systems that evaluate feature flags and experiments, ingest frontend analytics, and improve Dashboard load times for Stripe’s largest merchants.

We build backend-for-frontend capabilities that connect Stripe’s backend systems to its UI platform. This gives product teams a consistent way to build and operate user experiences without recreating the same infrastructure.

What you’ll do

As a Backend Engineer on the Sail Services team, you’ll help build and evolve the systems that power Stripe’s user interfaces. You’ll independently drive software projects from problem definition through production, working closely with other UI Platform engineers, product teams, and infrastructure partners. Your work will range from APIs and GraphQL integrations to edge systems, architectural migrations, and the tooling needed to operate them safely at scale.

Responsibilities

• Take end-to-end ownership of software projects, aligning on priorities and then independently scoping problems and carrying solutions through design, implementation, testing, rollout, and operation
• Design, build, and operate reliable, scalable APIs and backend systems that support Stripe’s Dashboard, mobile applications, and other user interfaces
• Help modernize Stripe’s UI architecture through incremental migrations, automated validation, shadow traffic, and carefully controlled production rollouts
• Improve the reliability, observability, performance, and operability of services on critical user paths
• Partner with frontend, backend, and infrastructure engineers to understand their needs and turn recurring problems into reusable platform capabilities
• Use AI-assisted and agentic development workflows to improve implementation, testing, validation, and delivery
• Contribute thoughtful code reviews, technical discussions, documentation, and runbooks that improve the quality of the team’s work

Who you are

We’re looking for someone who meets the minimum requirements to be considered for the role. If you meet these requirements, you are encouraged to apply. The preferred qualifications are a bonus, not a requirement.

Minimum requirements

• Fluency in using AI-assisted and agentic development tools as part of day-to-day software engineering, including critically reviewing, validating, and improving generated code
• 2+ years of professional software engineering experience, or equivalent practical experience, building, shipping, and operating production systems
• Strong knowledge of backend technologies and infrastructure, including the fundamentals of APIs, data storage, distributed systems, and production operations
• Ability to independently scope and deliver open-ended software projects, making practical technical and product tradeoffs with limited oversight
• Strong problem-solving and debugging skills, with attention to testing, maintainability, reliability, and user impact
• Strong written and verbal communication skills and the ability to collaborate effectively with frontend engineers, product engineers, and infrastructure partners

Preferred qualifications

• • Experience building backend-for-frontend systems, UI platform services, developer platforms, or shared infrastructure
  • Experience designing or integrating APIs, including GraphQL APIs
  • Experience with high-throughput event ingestion, feature flag or experimentation systems, or other latency-sensitive platform services
  • Familiarity with caching, asynchronous systems, configuration systems, or data-consistency tradeoffs
  • Experience executing large migrations using automated validation, shadow traffic, feature flags, or staged rollouts
  • Experience using data, developer feedback, or operational signals to improve a platform or developer-facing product