Backend Developer

🏢 Summary: The offer is for a backend-focused engineer working on modernising Java/Scala services and data pipelines, upgrading core frameworks, and migrating authentication to OAuth. The role involves heavy work with Spark-based batch pipelines and Play Framework services, with opportunities to apply GenAI tooling for large-scale code transformations. DevOps experience with build systems and CI/CD is an advantage. 🗂️ Requirements: Hands-on experience with production Java services, Hands-on experience with production Scala services, Familiarity with Play Framework internals, Experience with Spark for data pipelines, Experience with OAuth-based authentication patterns, Ability to modernise and upgrade JDK, Scala, and Play Framework versions, Experience building batch data migration pipelines, Experience extending and maintaining backend services 📃 Skills: Java, Scala, Play, Spark, OAuth, React, TypeScript, Gradle, CI/CD, JDK, GenAI 🏢 Description: What we're looking for • Hands-on experience with production Java/Scala services • Familiarity with the Play Framework internals • Spark experience for pipeline-heavy work • Comfortable with OAuth-based authentication patterns • React/TypeScript familiarity is a plus • For DevOps-leaning candidates: experience with build systems (Gradle), scripting, and CI/CD pipelines Example of work tasks • Modernise backend services and pipelines: upgrade to latest JDK, Scala 3.x, and Play Framework 3.x • Apply GenAI tooling throughout to automate code transformations, dependency resolution, and compatibility fixes — producing reusable tools, prompts, and a documented runbook • Migrate authentication across a large number of backend services from a legacy API to an OAuth-based solution. • Replace per-unit data stores with a single versioned table: build Spark/ Java batch pipelines for backfill/migration and extend Scala/Play backends

🏢 Summary: Backend Developer role focused on modernizing and optimizing backend services, upgrading core technologies, and implementing automation using GenAI tooling. The position involves migrating authentication systems to OAuth, consolidating data stores, and building Spark-based batch pipelines. It emphasizes performance improvements, scalable architecture, and robust backend engineering practices. 🗂️ Requirements: Hands-on experience with production Java services, Hands-on experience with production Scala services, Familiarity with Play Framework internals, Experience with Spark for pipeline-heavy workloads, Experience with OAuth-based authentication patterns 📃 Skills: Java, Scala, Play, Spark, OAuth, JDK, GenAI 🏢 Description: Summary The Backend Developer role is aimed at enhancing and modernizing backend services and pipelines within the organization. This position primarily focuses on improving system performance, ensuring robust authentication mechanisms, and implementing automation to streamline processes. Main Responsibilities Modernise backend services and pipelines by upgrading to the latest JDK, Scala 3.x, and Play Framework 3.x. Apply GenAI tooling to automate code transformations, dependency resolution, and compatibility fixes, producing reusable tools and documentation. Migrate authentication frameworks from legacy APIs to OAuth-based solutions across various backend services. Replace multiple data stores with a single versioned table, creating Spark/Java batch pipelines for backfill/migration and extending Scala/Play backends. Key Requirements Hands-on experience with production Java/Scala services. Familiarity with Play Framework internals. Experience with Spark for pipeline-heavy work. Comfortable with OAuth-based authentication patterns. Nice to Have Familiarity with React/TypeScript. For DevOps-leaning candidates: experience with Gradle, scripting, and CI/CD pipelines. Other Details Location: Not specified. Team Structure: Not specified. Tools/Methodologies: Java, Scala, Play Framework, Spark, OAuth.

🏢 Summary: Full-time hybrid Backend Developer contract focused on modernizing backend services, migrating authentication systems to OAuth, and building Spark-based data migration pipelines. The role involves upgrading Java/Scala ecosystems, automating transformations with GenAI tooling, and extending Scala/Play Framework backends in an English-speaking international environment. 🗂️ Requirements: Production experience with Java, Production experience with Scala, Knowledge of Play Framework internals, Experience with Spark, Knowledge of OAuth authentication patterns, Availability for hybrid work in Krakow, English proficiency 📃 Skills: Java, Scala, Play, Spark, OAuth, GenAI, React, TypeScript, Gradle, CI/CD 🏢 Description: Industry: Technology solutions - consumer electronics, software, streaming Client: global enterprise, Swedish entity Work model: full time, hybrid 3 days/week on-site fromKrakow (Equal Business Park) office Project language: English Onboarding : 3 days in Malmo, Sweden Start: ASAP or 1 week notice ideally / at latest start 27th July 2026 Assignment type: B2B Remuneration: up to 200 PLN/h net + VAT FTE: full-time Summary: The Backend Developer role is aimed at enhancing and modernizing backend services and pipelines within the organization. This position primarily focuses on improving system performance, ensuring robust authentication mechanisms, and implementing automation to streamline processes. Main Responsibilities: Modernise backend services and pipelines by upgrading to the latest JDK, Scala 3.x, and Play Framework 3.x. Apply GenAI tooling to automate code transformations, dependency resolution, and compatibility fixes, producing reusable tools and documentation. Migrate authentication frameworks from legacy APIs to OAuth-based solutions across various backend services. Replace multiple data stores with a single versioned table, creating Spark/Java batch pipelines for backfill/migration and extending Scala/Play backends. Key Requirements: Hands-on experience with production Java/Scala services . Familiarity with Play Framework internals or Akka. Experience with Spark for pipeline-heavy work. Comfortable with OAuth-based authentication patterns. Nice to Have: Familiarity with React/TypeScript. For DevOps-leaning candidates: experience with Gradle, scripting, and CI/CD pipelines.

🏢 Summary: Hybrid Backend Developer role focused on modernizing and optimizing backend services, upgrading core technologies, and improving authentication and data pipelines. The project involves Java/Scala development, Play Framework upgrades, Spark-based batch processing, and OAuth migration. B2B contract with fast recruitment process and onboarding in Sweden. 🗂️ Requirements: Hands-on experience with production Java services, Hands-on experience with production Scala services, Familiarity with Play Framework internals, Experience with Spark for pipeline-heavy work, Experience with OAuth-based authentication patterns, Fluent English for project communication 📃 Skills: Java, Scala, Play, Spark, OAuth, JDK, GenAI, Gradle, CI/CD, React, TypeScript 🏢 Description: 🌍 Work mode: hybrid –  3 days from the Warsaw office. 🔍 Onboarding : 2 weeks in Malmo, Sweden. ⏰ Start : 1 week notice period, August 3rd at the latest. 📝 Contract : B2B > up 195 zl/h. ⚙️ Recruitment process : 1 meeting with the client. ⏳ Duration : > 3 months contracts + extensions. 📕Project language : English. 💼 Industry : Technology. 💻 Workload : Full time (40 hours per week). Summary: The Backend Developer role is aimed at enhancing and modernizing backend services and pipelines within the organization. This position primarily focuses on improving system performance, ensuring robust authentication mechanisms, and implementing automation to streamline processes. Main Responsibilities: Modernise backend services and pipelines by upgrading to the latest JDK, Scala 3.x, and Play Framework 3.x. Apply GenAI tooling to automate code transformations, dependency resolution, and compatibility fixes, producing reusable tools and documentation. Migrate authentication frameworks from legacy APIs to OAuth-based solutions across various backend services. Replace multiple data stores with a single versioned table, creating Spark/Java batch pipelines for backfill/migration and extending Scala/Play backends. Key Requirements: Hands-on experience with production Java/Scala services . Familiarity with Play Framework internals. Experience with Spark for pipeline-heavy work. Comfortable with OAuth-based authentication patterns. Nice to Have: Familiarity with React/TypeScript. For DevOps-leaning candidates: experience with Gradle, scripting, and CI/CD pipelines. Other Details Tools/Methodologies: Java, Scala, Play Framework, Spark, OAuth.

🏢 Summary: Backend Developer role focused on modernizing and optimizing backend services and data pipelines, including technology upgrades, authentication migration, and automation initiatives. The position involves working with Java/Scala ecosystems, Spark pipelines, and OAuth-based security in a hybrid model with onboarding in Sweden. B2B contract with competitive hourly rate and English as the project language. 🗂️ Requirements: Hands-on experience with production Java services, Hands-on experience with production Scala services, Familiarity with Play Framework internals, Experience with Spark for data pipelines, Experience with OAuth-based authentication patterns, Availability for hybrid work (3 days/week in Warsaw or Cracow), Availability for 2-week onboarding in Malmo, Sweden, Fluent English 📃 Skills: Java, Scala, Play, Spark, OAuth, Gradle, CI/CD, React, TypeScript 🏢 Description: 🌍 Work mode: hybrid –  3 days from the Warsaw OR Cracow office. ⏳ Duration : > 3 months contracts . 🔍 Onboarding : 2 weeks in Malmo, Sweden. ⏰ Start : August 3rd at the latest. 📝 Contract : B2B > up 200 zl/h. ⚙️ Recruitment process : 2 meetings. 📕Project language : English. 💼 Industry : Technology. 💻 Workload : Full time (40 hours per week). Summary: The Backend Developer role is aimed at enhancing and modernizing backend services and pipelines within the organization. This position primarily focuses on improving system performance, ensuring robust authentication mechanisms, and implementing automation to streamline processes. Main Responsibilities: Modernise backend services and pipelines by upgrading to the latest JDK, Scala 3.x, and Play Framework 3.x. Apply GenAI tooling to automate code transformations, dependency resolution, and compatibility fixes, producing reusable tools and documentation. Migrate authentication frameworks from legacy APIs to OAuth-based solutions across various backend services. Replace multiple data stores with a single versioned table, creating Spark/Java batch pipelines for backfill/migration and extending Scala/Play backends. Key Requirements: Hands-on experience with production Java/Scala services . Familiarity with Play Framework internals. Experience with Spark for pipeline-heavy work. Comfortable with OAuth-based authentication patterns. Nice to Have: Familiarity with React/TypeScript. For DevOps-leaning candidates: experience with Gradle, scripting, and CI/CD pipelines. Other Details Tools/Methodologies: Java, Scala, Play Framework, Spark, OAuth.

🏢 Summary: Backend Developer role focused on modernizing and optimizing backend services and data pipelines, including migration to newer Java/Scala and Play Framework versions and implementation of OAuth-based authentication. The position involves automation with GenAI tools and Spark-based data migrations in a hybrid work model. B2B contract with onboarding in Sweden and full-time engagement in English. 🗂️ Requirements: Hands-on experience with production Java services, Hands-on experience with production Scala services, Experience with Play Framework internals, Experience with Spark for pipeline-heavy work, Experience with OAuth-based authentication patterns, Availability to work hybrid from Warsaw or Cracow office, Availability for 2-week onboarding in Malmo, Sweden, Fluency in English 📃 Skills: Java, Scala, Play, Spark, OAuth, JDK, GenAI, Gradle, CI/CD, React, TypeScript 🏢 Description: 🌍 Work mode: hybrid –  3 days from the Warsaw OR Cracow office. ⏳ Duration : > 3 months contracts . 🔍 Onboarding : 2 weeks in Malmo, Sweden. ⏰ Start : August 3rd at the latest. 📝 Contract : B2B > up 195 zl/h. ⚙️ Recruitment process : 2 meetings. 📕Project language : English. 💼 Industry : Technology. 💻 Workload : Full time (40 hours per week). Summary: The Backend Developer role is aimed at enhancing and modernizing backend services and pipelines within the organization. This position primarily focuses on improving system performance, ensuring robust authentication mechanisms, and implementing automation to streamline processes. Main Responsibilities: Modernise backend services and pipelines by upgrading to the latest JDK, Scala 3.x, and Play Framework 3.x. Apply GenAI tooling to automate code transformations, dependency resolution, and compatibility fixes, producing reusable tools and documentation. Migrate authentication frameworks from legacy APIs to OAuth-based solutions across various backend services. Replace multiple data stores with a single versioned table, creating Spark/Java batch pipelines for backfill/migration and extending Scala/Play backends. Key Requirements: Hands-on experience with production Java/Scala services . Familiarity with Play Framework internals. Experience with Spark for pipeline-heavy work. Comfortable with OAuth-based authentication patterns. Nice to Have: Familiarity with React/TypeScript. For DevOps-leaning candidates: experience with Gradle, scripting, and CI/CD pipelines. Other Details: Tools/Methodologies: Java, Scala, Play Framework, Spark, OAuth.

🏢 Summary: Senior Backend Engineer role for a 3-month modernization project focused on upgrading Java and Scala backend services, migrating authentication systems to OAuth, and building large-scale Spark data pipelines. The position requires hybrid work in Warsaw or Kraków, with a fully covered onboarding period in Sweden. 🗂️ Requirements: 5+ years commercial backend experience, Strong production experience with Java, Strong production experience with Scala, Experience with Play Framework or Akka/Pekko, Hands-on experience with Spark, Experience with OAuth authentication, Professional English proficiency, Availability for 2-week onboarding in Sweden, Hybrid availability in Warsaw or Kraków office 3 days/week 📃 Skills: Java, Scala, Play, Akka, Pekko, Spark, OAuth, React, TypeScript, CI/CD, Gradle 🏢 Description: co.brick talents — powered by AI, powered by people. Senior Backend Engineer (Scala / Java) – 3-Month Project Salary: Up to 175 PLN/h net + VAT (B2B Contract) Location: Hybrid – Warsaw or Kraków ( strictly 3 days/week from the office – non-negotiable) Onboarding: 2 weeks on-site in Malmö, Sweden (fully covered) Project Duration: 3 months Start Date: ASAP/Beginning of August at the ABSOLUTE LATEST About the Client & Project On behalf of our client, an innovative company from the technology sector, we are looking for a Strong Senior Backend Developer to join a short-term, high-impact project. The main goal is to modernize and optimize core backend services, streamline data pipelines, and enhance system security. This is a highly autonomous role requiring a seasoned engineer who can jump straight into a complex ecosystem, utilize automation tools for framework upgrades, and handle heavy data migration tasks. Key Responsibilities Modernize and refactor backend services by upgrading legacy Java and Scala-based frameworks. Leverage automation and modern tooling to expedite code transformations, dependency resolution, and compatibility fixes. Migrate legacy authentication mechanisms across various services to secure, OAuth-based solutions. Consolidate multiple data stores into unified, versioned tables by designing and executing heavy Spark/Java batch pipelines. Requirements Minimum of 5 years of commercial backend experience (7+ years is highly preferred). Deep production experience with Java and Scala . Strong familiarity with Play Framework OR Akka (experience with Akka/Pekko is highly acceptable if you are ready to work with Play environments). Hands-on experience with Spark for complex, heavy data pipeline processing. Solid understanding and practical experience with OAuth authentication patterns. Excellent communication skills with Full Professional English (the project language is 100% English). Full availability for a 2-week onboarding trip to Sweden at the very start of the contract. Nice to Have Basic understanding or exposure to frontend technologies (React / TypeScript). DevOps mindset: familiarity with CI/CD pipelines, Gradle, and scripting. What We Offer A transparent, quick 2-stage recruitment process. An attractive hourly rate with seamless B2B invoicing. An opportunity to work on a high-exposure architectural modernization project for an international client.

🏢 Summary: Senior Backend Engineer role for a 3-month modernization project focused on upgrading Java and Scala backend services, migrating authentication systems to OAuth, and building heavy Spark-based data pipelines. The position requires hybrid work in Warsaw or Kraków with an initial onboarding in Sweden. 🗂️ Requirements: 5+ years commercial backend experience, Production experience with Java, Production experience with Scala, Experience with Play Framework or Akka/Pekko, Hands-on Spark experience, Experience with OAuth authentication, Professional English proficiency, Availability for 2-week onboarding in Sweden, Hybrid availability 3 days/week in Warsaw or Kraków office 📃 Skills: Java, Scala, Play, Akka, Pekko, Spark, OAuth, React, TypeScript, CI/CD, Gradle 🏢 Description: co.brick talents — powered by AI, powered by people. Senior Backend Engineer (Scala / Java) – 3-Month Project Salary: Up to 175 PLN/h net + VAT (B2B Contract) Location: Hybrid – Warsaw or Kraków ( strictly 3 days/week from the office – non-negotiable) Onboarding: 2 weeks on-site in Malmö, Sweden (fully covered) Project Duration: 3 months Start Date: ASAP/Beginning of August at the ABSOLUTE LATEST About the Client & Project On behalf of our client, an innovative company from the technology sector, we are looking for a Strong Senior Backend Developer to join a short-term, high-impact project. The main goal is to modernize and optimize core backend services, streamline data pipelines, and enhance system security. This is a highly autonomous role requiring a seasoned engineer who can jump straight into a complex ecosystem, utilize automation tools for framework upgrades, and handle heavy data migration tasks. Key Responsibilities Modernize and refactor backend services by upgrading legacy Java and Scala-based frameworks. Leverage automation and modern tooling to expedite code transformations, dependency resolution, and compatibility fixes. Migrate legacy authentication mechanisms across various services to secure, OAuth-based solutions. Consolidate multiple data stores into unified, versioned tables by designing and executing heavy Spark/Java batch pipelines. Requirements Minimum of 5 years of commercial backend experience (7+ years is highly preferred). Deep production experience with Java and Scala . Strong familiarity with Play Framework OR Akka (experience with Akka/Pekko is highly acceptable if you are ready to work with Play environments). Hands-on experience with Spark for complex, heavy data pipeline processing. Solid understanding and practical experience with OAuth authentication patterns. Excellent communication skills with Full Professional English (the project language is 100% English). Full availability for a 2-week onboarding trip to Sweden at the very start of the contract. Nice to Have Basic understanding or exposure to frontend technologies (React / TypeScript). DevOps mindset: familiarity with CI/CD pipelines, Gradle, and scripting. What We Offer A transparent, quick 2-stage recruitment process. An attractive hourly rate with seamless B2B invoicing. An opportunity to work on a high-exposure architectural modernization project for an international client.

🏢 Summary: Scala/Spark Developer role focused on building and optimizing scalable data processing applications and distributed systems using modern big data technologies. The position involves developing ETL/ELT pipelines, improving Spark performance, and collaborating on international AI and data engineering projects. The offer includes flexible working conditions, private healthcare, training opportunities, and a B2B salary range of 28,500–30,000 PLN + VAT. 🗂️ Requirements: Commercial experience with Scala in production environments, Knowledge of functional programming concepts in Scala, Experience with Scala type system, collections, sbt, and testing frameworks, Hands-on experience with Apache Spark, Experience with Spark SQL and DataFrame/Dataset API, Experience designing and maintaining ETL/ELT pipelines, Knowledge of Spark performance optimization techniques, Experience troubleshooting Spark applications using Spark UI, Experience with large-scale distributed data processing, Understanding of software engineering best practices and code quality 📃 Skills: Scala, Spark, SparkSQL, DataFrame, Dataset, ETL, ELT, sbt, ScalaTest, munit, SparkUI, Kafka, Airflow, AWS, EMR, S3, Glue, Azure, GCP, Dataproc, Databricks, Hadoop, Hive, DeltaLake, Parquet, Avro, SQL, Docker, Kubernetes, Git, CI/CD, Cats, ZIO, Akka, Pekko, Python, Java 🏢 Description: Scala/Spark Developer We are looking for a Scala/Spark Developer to join an AI-first software engineering company delivering innovative AI, data, cloud, and IoT solutions for clients across Europe and beyond. As part of the engineering team, you will design, develop, and optimize scalable data processing solutions, build high-performance distributed systems, and work with modern big data technologies on challenging international projects. Responsibilities Design, develop, and maintain scalable data processing applications using Scala and Apache Spark; Build, optimize, and maintain ETL/ELT pipelines processing large volumes of data; Develop efficient Spark applications using Spark SQL and the DataFrame/Dataset API; Optimize Spark jobs by improving partitioning strategies, shuffle operations, caching, and join performance; Troubleshoot and resolve performance issues using Spark UI and monitoring tools; Collaborate with data engineers, software developers, and stakeholders to design scalable data processing solutions; Participate in code reviews and contribute to software quality, performance, and engineering best practices. Requirements Strong commercial experience developing production applications in Scala, including functional programming concepts (immutability, pattern matching, higher-order functions), Scala type system, collections, sbt, and testing frameworks such as ScalaTest or munit, with the ability to write clean, maintainable, production-quality code; Proven hands-on experience with Apache Spark, including Spark SQL, DataFrame/Dataset API, designing and maintaining ETL/ELT pipelines, performance optimization (partitioning, shuffle optimization, broadcast joins, caching), and troubleshooting using Spark UI; Experience working in production environments with large-scale data processing and distributed data pipelines; Strong understanding of software engineering best practices, code quality, performance optimization, and maintainability. Nice to have Experience with Kafka and Spark Structured Streaming; Experience with Airflow or similar workflow orchestration tools; Experience with cloud platforms such as AWS (EMR, S3, Glue), Azure, GCP (Dataproc), or Databricks; Knowledge of the big data ecosystem, including Hadoop, Hive, Delta Lake, Parquet, and Avro; Experience with SQL, data modeling, data warehouses, and data lake architectures; Experience with Docker, Kubernetes, Git, and CI/CD pipelines; Familiarity with Scala libraries such as Cats, ZIO, Akka, or Pekko; Knowledge of Python or Java. We offer B2B salary: 28 500 -30 000 PLN + VAT; Flexible working conditions; Private healthcare, Multisport card, and professional training opportunities.

🏢 Summary: Senior Backend Test Automation Engineer role focused on testing backend microservices and distributed data platforms in a global technology environment. The position involves integration testing, ETL/data pipeline validation, and automated test execution using JVM-based technologies and Apache Spark. Hybrid work model based in Krakow with onboarding in Sweden and collaboration in English. 🗂️ Requirements: Strong experience testing backend microservices, Hands-on experience with integration testing across distributed systems, Experience with Play Framework or JVM-based backend services in Java/Scala, Good understanding of Apache Spark, Experience testing ETL and data processing workflows, Ability to manage test data and deterministic test environments, Experience with CI/CD and automated test execution, Ability to debug failures across services, databases, queues, and pipelines, English proficiency, Availability for hybrid work in Krakow 📃 Skills: Java, Scala, Play, Spark, SQL, ScalaTest, JUnit, Testcontainers, Docker, Kubernetes, GitHub, Jenkins, Azure, CI/CD, ETL 🏢 Description: We are looking for a Senior Backend Test Automation Engineer with strong data platform experience. Industry: Technology solutions - consumer electronics, software, streaming Client: global enterprise, Swedish entity Work model: full time, hybrid 3 days/week on-site from Krakow (Equal Business Park) office Project language: English Onboarding: 3 days in Malmo, Sweden Start: ASAP or 1 week notice ideally / at latest start 27th July 2026 Assignment type: B2B Remuneration: up to 200 PLN/h net + VAT FTE: full-time Requirements: - Strong experience testing backend microservices rather than web UIs - Hands-on experience with integration testing across distributed systems - Experience with Play Framework or JVM-based backend services in Java/Scala - Good understanding of Apache Spark and testing data pipelines - Experience validating ETL/data processing workflows - Comfortable managing test data, data dependencies, and deterministic test environments - Experience with CI/CD and automated test execution - Ability to debug failures across multiple services, databases, queues, and pipelines Likely technical stack includes: - Java and/or Scala - Play Framework - Apache Spark - SQL - Integration test frameworks (ScalaTest, JUnit, Testcontainers, etc.) - Docker/Kubernetes - GitHub Actions, Jenkins, Azure DevOps, or similar