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# Senior Back-End Js Engineer - €350 - €380 A Day

- **Company:** Forsyth Barnes
- **Location:** Madrid, Spain
- **Salary:** €91,000.0 - €98,800.0
- **Contract:** Permanent contract
- **Skills:** Clean Code Principles, Backend, Kotlin, Kubernetes, Front End Software Development, Elk Stack
- **Published:** September 27, 2026
- **Apply:** https://www.buscojobs.com.es/senior-back-end-js-engineer-%E2%82%AC-350-%E2%82%AC-380-a-day-en-madrid-ID-372703700

## About the Role

You'll play a key role in shaping core financial products, supporting a rapidly growing user base, and delivering high-quality solutions in a fast-paced environment.Design, develop, deploy, and maintain backend services aligned with team and business goalsBackend: Frontend: React.JsMobile: Kotlin, SwiftInfrastructure: Kubernetes on AWSDatabase: PostgreSQLKafka, ELK stack, and other modern toolsCash flow management and bookkeeping toolsEach team typically includes 6-8 backend engineers and owns its product scope end to end.Quality-oriented: Strong advocate for testing, clean code, and constructive code reviewsLanguage: Fluent in EnglishA remote or onsite technical exercise to showcase your skills and experience what it's like to work with the team

## Description

Senior Backend Developer Contract Role: Day Rate: €350-€380 per day8-12 month contractYou'll join a large, distributed backend engineering community and work within cross-functional teams alongside product managers, frontend, and mobile engineers.You'll play a key role in shaping core financial products, supporting a rapidly growing user base, and delivering high-quality solutions in a fast-paced environment.Design, develop, deploy, and maintain backend services aligned with team and business goalsBackend: Frontend: React.JsMobile: Kotlin, SwiftInfrastructure: Kubernetes on AWSDatabase: PostgreSQLKafka, ELK stack, and other modern toolsCash flow management and bookkeeping toolsEach team typically includes 6-8 backend engineers and owns its product scope end to end.Quality-oriented: Strong advocate for testing, clean code, and constructive code reviewsLanguage: Fluent in EnglishA remote or onsite technical exercise to showcase your skills and experience what it's like to work with the team