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Senior Software Engineer - Web App & DevEx

Remote from Spain·Added 16 days ago (last checked 4 Nov)

Runware

5 open roles

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Our summary

Work mode: Remote from Spain
English: Required
Experience: Senior level

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Skills

Nice to have

Requirements

What we're looking for

Strong experience building backend systems and APIs
Strong programming experience in one or more backend languages, with the ability to quickly learn and work effectively in new languages and technologies
Experience building reliable, maintainable and well-tested production systems
Good understanding of API design, asynchronous workloads and distributed systems concepts
Strong engineering fundamentals around security, reliability and performance
Strong communication and collaboration skills, with the ability to work effectively across engineering, Product and Design
Strong ownership and autonomy, with good judgement around when to involve others
Comfortable using AI-assisted development tools and agents to improve productivity, while understanding their limitations and maintaining responsibility for the quality, security and correctness of the resulting code

Nice to have

Experience with PHP, Symfony and/or Doctrine
Experience with WebSockets
Experience building public APIs or other developer-facing products
Experience with usage-based billing, credits or financial data
Experience contributing to architectural decisions and mentoring other engineers

Pay & benefits

What you'll get

We're a remote-first collective, meeting in person twice a year to plan, brainstorm, celebrate wins, and enjoy some face-to-face time. We have core hours for cooperative working and calls, but outside of that your calendar is yours. Work the hours that let you perform at your peak while also building a healthy life.

We move quickly and hold a high bar, but we also believe sustainable performance matters. After major releases and milestones, we create space for the team to properly unplug, recharge and come back with the energy to tackle what's next.

Generous paid time off - vacation, sick days, public holidays
Meaningful stock options - share in the upside you create
Remote-first setup - work from home anywhere we can employ you
Flexible hours - own your schedule outside core collaboration blocks
Family leave - paid maternity, paternity, and caregiver time
Company retreats - twice-yearly gatherings in inspiring locations

The role

We're looking for a Senior Software Engineer to help build and evolve the systems and APIs that power Runware's Web App and Developer Experience (DevEx).

You'll work closely with backend engineers, frontend engineers, Product, Design and other teams to build reliable internal and developer-facing APIs and functionality that make complex AI infrastructure simple to use.

You'll take ownership of backend work from understanding requirements and technical constraints through to implementation and delivery, contributing to the quality, reliability and evolution of the Web App and its supporting APIs.

This role combines technical depth with product thinking and collaboration. You'll be expected to work autonomously, contribute to technical decisions and help turn ambitious ideas into robust production systems.

What you'll do

What you'll do

Build and maintain internal and developer-facing APIs and services that power the Web App and developer experience
Develop and evolve public API functionality, including task types, validation, routing and WebSocket/REST behaviour
Own and maintain the Admin API and panel as an internal platform used across Runware
Work with usage, billing and customer data to ensure accuracy and reliability, including Stripe
Investigate and resolve production issues and security vulnerabilities affecting the Web App and its APIs
Write, test and review clean, maintainable code, contributing to strong engineering practices and code quality
Work with Product, Design and engineering teams to clarify requirements, identify dependencies and define well-scoped technical solutions
Contribute to technical decisions, work across frontend and backend boundaries where appropriate, and collaborate with the wider Backend team where specialist knowledge or shared systems are involved

About Runware

Runware is a technology company specializing in AI inference infrastructure, providing GPU cloud services and APIs for running machine learning models at scale. The company focuses on making AI compute accessible and efficient for developers and enterprises, with a strong emphasis on performance and cost optimization. Runware operates globally, serving clients who need reliable and scalable AI inference solutions.

Runware has its headquarters in Madrid, Spain, making it a Spanish-founded company with a growing international presence. The company's work culture is centered on innovation and technical excellence, attracting engineers and AI specialists from around the world. For international professionals, Runware offers the opportunity to work in a dynamic AI startup environment in Spain, with a focus on cutting-edge technology and a collaborative team atmosphere.

Founded: 2023
Employees: 11–50
Headquarters: Madrid, Spain
In Spain: Madrid

Good to know if you are moving

Runware is headquartered in Madrid, Spain, offering a central location in a vibrant European tech hub.
The company is at the forefront of AI infrastructure, providing opportunities to work with cutting-edge GPU technologies and machine learning models.
As a relatively young startup, Runware offers a dynamic and fast-paced work environment where employees can have a significant impact.
The company's global client base means that English is likely the primary working language, making it accessible for international professionals.
Spain's digital nomad visa and startup-friendly ecosystem make it easier for international tech workers to relocate and join companies like Runware.

All open roles at Runware