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# Mid Backend Engineer (Data-Focused) (Python / Etl) | €35K - €50K

- **Company:** Joppy
- **Location:** Madrid, Spain
- **Salary:** €35,000.0 - €50,000.0
- **Contract:** Permanent contract
- **Skills:** Query Performance, Unit Testing, Big Data, Code Review, Continuous Integration, Data Validation, Extract Transform Load (ETL), Data Security, Database Schema, Python (Programming Language), NoSQL, Query Optimization, SQL Databases, Backend, Containerization, Integration Tests, Production Code, Data Pipelines, Docker
- **Published:** August 5, 2026
- **Apply:** https://www.buscojobs.com.es/mid-backend-engineer-data-focused-python-etl-%E2%82%AC-35-k-%E2%82%AC-50-k-en-madrid-ID-365486281

## About the Role

Strong Python engineering skills (at least 3 years of professional experience) with emphasis on performance and production-quality code.
Experience building and operating ETL/ELT data pipelines, pipeline orchestration, and large-scale data ingestion.
Familiarity with SQL and NoSQL databases, including schema design and query optimization.
Ability to work autonomously, taking high-level requirements from scope definition to production.
Capability to quickly understand and contribute to unfamiliar codebases.
Experience with CI/CD workflows and containerization (e.g., Docker).
Professional proficiency in both English and Spanish.

## Description

We're looking for a skilledMid-Level Data Engineer for one of our clients (TOP Startup)to design, build, and optimize data pipelines and backend services that ensure clean, reliable data across the organization.Design, develop, and maintain scalable ETL/ELT pipelines to ingest, transform, and load data from multiple sources.Write clean, efficient Python code with a focus on performance, memory efficiency, and maintainability.Collaborate on database schema design (SQL and NoSQL) and optimize query performance for fast, accurate data access.Implement unit tests, integration tests, and data quality checks to ensure pipeline integrity and prevent issues before production.Deploy and iterate on pipelines using CI/CD practices and containerization tools such as Docker, and participate actively in code reviews.Strong Python engineering skills (at least 3 years of professional experience) with emphasis on performance and production-quality code.Experience building and operating ETL/ELT data pipelines, pipeline orchestration, and large-scale data ingestion.Familiarity with SQL and NoSQL databases, including schema design and query optimization.Ability to work autonomously, taking high-level requirements from scope definition to production.Capability to quickly understand and contribute to unfamiliar codebases.Experience with CI/CD workflows and containerization (e.g., Docker).Professional proficiency in both English and Spanish.Full-time, permanent contractSalary range of €35,000-€50,000 gross per year, based on experienceAn office with stunning views of BarcelonaFlexible working hours and hybrid work optionsPaid day off on your birthdayWeekly fresh fruit, coffee, and teaFriday happy hours (optional)Team-building eventsHealth insurance and flexible compensationYearly training budget for continuous growth#J-*****-Ljbffr