# Senior Backend Engineer at Lionhires

> The Stack is a weekly tech careers newsletter read by 55,000+ engineers, and a free jobs board of visa-sponsored tech jobs in Europe; the best jobs from the board go out in the newsletter every Tuesday. This is one job from the board.

> Responsibilities: - Lead design and development of the core

- **Company:** Lionhires (https://jobs.trythestack.co/companies/lionhires)
- **Location:** Spain
- **Work arrangement:** On-site
- **Employment type:** Full-time
- **Experience level:** 5–10 years
- **Visa sponsorship:** Offered, according to the listing
- **Key skills:** Node.js, Nest.js, TypeScript, MongoDB, MySQL, RESTful APIs, GraphQL, WebSockets, RabbitMQ, Redis, Microservices Architecture, TDD, Git, CI/CD, Kubernetes, JavaScript
- **Posted by employer:** 2026-06-25
- **Added to The Stack:** 2026-06-29
- **Status:** May no longer be active (posted more than 60 days ago)
- **Apply:** https://job-boards.eu.greenhouse.io/lionhires/jobs/4908061101 (the employer's own application page)
- **Human page:** https://jobs.trythestack.co/jobs/senior-backend-engineer-lionhires

## About the role

Responsibilities:
- Lead design and development of the core in-house platform using Node.js / Nest.js.
- Build and maintain microservices, integrating with third-party APIs and external systems.
- Optimize databases for high-load scenarios using MongoDB and MySQL; implement caching with Redis.
- Implement and maintain APIs (REST, GraphQL) and realtime communication (WebSockets).
- Apply TDD principles and write automated test suites to ensure code quality and reliability.
- Collaborate across product, UX, QA, and operations to ship scalable, production-grade features.
- Participate in CI/CD, containerization, and performance monitoring; contribute to architecture decisions.

Requirements:
- 5+ years commercial backend development experience with strong Node.js and Nest.js expertise.
- Proficient in modern JavaScript/TypeScript (ES6+) and server-side architecture patterns.
- Experience with high-load data stores (MongoDB, MySQL) and message brokers (RabbitMQ); Redis experience.
- Practical experience with RESTful APIs, GraphQL, and WebSockets.
- Strong understanding of microservices, version control (Git), and TDD practices.
- Professional working proficiency in English.
- Nice to have: hands-on CI/CD, container orchestration, and Kubernetes experience.

## Responsibilities

Architect and develop a core in-house platform by designing robust microservices and integrating third-party APIs. Optimize database performance for high-load systems and ensure code quality through TDD and automated testing.

## Requirements

Requires over 5 years of commercial experience in Node.js and Nest.js with proficiency in TypeScript and high-load database management. Candidates must have experience with message brokers like RabbitMQ and professional working proficiency in English.

## FAQ

- **Is this Senior Backend Engineer role still open?** It was posted on 2026-06-25. Listings more than 30 days old may no longer be active, so check Lionhires's site before applying.
- **Does Lionhires offer visa sponsorship?** This listing is marked as offering visa sponsorship. Eligibility rules are set by the employer, so check the details on Lionhires's site.
- **Where is this role located?** The listing gives the location as Spain. It is marked on-site.
- **What skills does this role ask for?** The listing names: Node.js, Nest.js, TypeScript, MongoDB, MySQL, RESTful APIs, GraphQL, WebSockets, RabbitMQ, Redis, Microservices Architecture, TDD, Git, CI/CD, Kubernetes, JavaScript.

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## About The Stack

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## Notes for agents

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