Senior Software Engineer (Scala & Python)

🏢 Summary: Senior Full Stack Software Engineer role focused on building and scaling a production-ready AI product, covering feature development, infrastructure, and client integrations. The position involves hands-on work with Python, DevOps/MLOps, and GenAI solutions, ensuring system reliability and production readiness. This is a remote contract role with expected extensions. 🗂️ Requirements: Strong Python development experience, DevOps expertise with CI/CD pipelines, MLOps experience with automated deployment and monitoring, Experience building agentic AI products, Experience with API integrations, Hands-on experience with GenAI/LLM, Ability to harden systems for production, Experience fine-tuning AI models, Experience with prompt engineering 📃 Skills: Python, CI/CD, DevOps, MLOps, GenAI, LLM, APIs, Automation, Deployment, Monitoring, Fine-tuning, Prompt-engineering 🏢 Description: Location : Remote with occasional visits to Łódź Employment type : 2 months initial contract - to be extended, B2B/Umowa Zlecenie Salary: up to 160zł/hour (B2B) Senior Software Engineer – AI Product (Full Stack) We’re looking for a Senior Software Engineer to help build and scale a production-ready AI product. This is a hands-on, full-stack role covering feature development, infrastructure, and client integration. What you’ll do Design, build, and deploy new features in Python Own DevOps/MLOps: CI/CD pipelines, automated model deployment, monitoring Integrate AI solutions into client-facing products Improve system reliability, performance, and production readiness Enhance AI models through fine-tuning and prompt engineering Contribute to short-term R&D initiatives and product innovation Build and evolve internal systems for model evaluation and performance tracking Must-have Strong Python development experience DevOps & MLOps expertise (CI/CD, automation, deployment) Experience building agentic AI products and API integrations Hands-on GenAI/LLM experience (classic ML not required) Proven ability to harden systems for production Nice to have Experience building model evaluation/monitoring systems Fine-tuning, prompt engineering, and performance optimization Details Contract extensions expected If you enjoy building real-world AI products end-to-end—from models to production—we’d love to hear from you.

🏢 Summary: B2B Software Engineer (Python – GenAI) role focused on building and deploying AI-driven applications using AWS and Large Language Models. The position involves developing backend services, APIs, and microservices while ensuring high standards of security, testing, and CI/CD within an Agile environment. Hybrid work model with regular collaboration in Scrum teams. 🗂️ Requirements: Strong Python backend development, Hands-on experience with AWS services (Bedrock, DynamoDB, OpenSearch, CloudWatch, Step Functions), Practical knowledge of Generative AI and LLM technologies, Experience building REST APIs, Experience developing microservices, Understanding of CI/CD pipelines in AWS, Knowledge of DevOps practices, Experience working in Agile/Scrum teams 📃 Skills: Python, AWS, Bedrock, DynamoDB, OpenSearch, CloudWatch, StepFunctions, LLM, GenAI, REST, Microservices, CICD, DevOps, Agile 🏢 Description: Location: hybrid model. For candidates based in Warsaw, Gdańsk , or nearby areas, we require office presence once per week . For candidates located in other regions, office visits are required once per month (for workshops and team meetings). Team Structure: Agile/Scrum teams Contract B2B Rates depending on the years of the experience: 4-7 yrs: 147 PLN/h 7-10 yrs: 164 PLN/h 10+ yrs: 178 PLN/h Software Engineer (Python – GenAI) role is to contribute to the development and deployment of AI-driven applications, focusing on leveraging modern cloud services and generative AI technologies to provide innovative solutions for the organization. Main Responsibilities: Creating, developing, and deploying AI-based applications using AWS services. Developing and optimizing Large Language Model (LLM) based solutions tailored to real-world business cases. Building and maintaining APIs and microservices to efficiently serve solutions to customers. Ensuring all AI solutions adhere to security, development, and governance standards. Writing and maintaining unit tests, ensuring robust test coverage, and enforcing best coding practices (clean code, maintainability, and performance optimization). Creating clear, concise technical documentation for developed components. Working in Agile/Scrum teams to deliver high-quality applications. Key Requirements: Fluency in English. Strong command of Python for backend development. Hands-on experience with AWS services, including Amazon Bedrock, DynamoDB, OpenSearch, CloudWatch, and Step Functions. Understanding of Generative AI and LLM technologies. Proven experience in developing and maintaining RESTful APIs and microservices. Solid understanding of CI/CD pipelines and DevOps best practices within the AWS environment. Ability to thrive in an Agile environment and work effectively with multidisciplinary teams. Nice to Have: Experience working with vector databases. Knowledge of prompt engineering. Experience working with Azure services, including Azure VM, Azure DevOps, Azure Blob Storage, Cosmos DB, Azure Functions, Azure AI Search, and others.

🏢 Summary: Senior Backend Python Engineer role focused on building scalable AI-powered enterprise software and owning backend services from architecture to production. The position involves backend development, distributed systems, cloud infrastructure, and technical leadership in a hybrid B2B environment. Candidates will collaborate across teams to deliver secure, high-performance applications using modern engineering and AI-assisted workflows. 🗂️ Requirements: 6+ years building production-grade backend systems, Strong Python experience, Experience with distributed systems, Knowledge of concurrency and asynchronous processing, Experience designing REST APIs, Experience with scalable architectures, Hands-on cloud platform experience, Database design and performance optimization knowledge, Experience building secure enterprise applications, Ability to own projects from design to deployment, Cross-functional collaboration skills, Strong troubleshooting and problem-solving skills, Excellent English communication skills, Experience with AI tooling and automation workflows 📃 Skills: Python, REST, AWS, GCP, Azure, SQL, TypeScript, LLM, AI, Monitoring, Logging, Observability, Automation 🏢 Description: Senior Backend Engineer (Python) 📍 Warsaw, Poland (Hybrid) ☑️ Full-time 🕦 B2B Contract 💰 $8.000 - $12.000/month We are hiring a Senior Backend Python Engineer for an innovative technology company building AI-powered enterprise software used by organizations worldwide. This role is ideal for an experienced backend engineer who enjoys designing scalable production systems, solving complex technical challenges, and taking ownership of critical backend services from architecture through production. You'll work closely with product, frontend, and platform engineers to build reliable, secure, and high-performance applications while leveraging modern AI-assisted engineering practices . As a Senior Backend Python Engineer you will provide backend development, system design, cloud infrastructure, and technical leadership in a fast-paced engineering environment where ownership and continuous improvement are highly valued. Requirements 6+ years of experience building and maintaining production-grade backend systems Strong hands-on experience with Python and modern backend development practices Strong understanding of distributed systems, concurrency, asynchronous processing, and scalable architectures Experience designing and developing REST APIs and backend services Hands-on experience with cloud platforms such as AWS, GCP, or Azure Strong knowledge of database design, performance optimization, and high-throughput applications Experience building secure, reliable enterprise applications with a security-first mindset Ability to own projects from technical design through deployment and production support Experience working closely with cross-functional engineering and product teams Strong troubleshooting, problem-solving, and communication skills Excellent written and verbal English communication skills Improve engineering leverage with AI tooling , automation, and internal workflows rather than using AI as a gimmick Nice to Have Experience building AI-powered applications, agentic systems, LLM integrations, or orchestration frameworks Experience with TypeScript or full-stack development Experience mentoring engineers or contributing to technical leadership Experience with observability, monitoring, logging, and performance optimization Experience working in fast-growing product or startup environments Responsibilities Design, develop, and maintain scalable backend services, APIs, and asynchronous processing systems Translate business requirements into robust technical solutions and scalable system designs Own services throughout their lifecycle, including deployment, monitoring, reliability, and continuous improvement Design efficient data models and optimize database performance for production workloads Collaborate with product, frontend, and platform teams to deliver end-to-end features Improve engineering productivity through automation and AI-assisted development workflows Participate in architecture discussions, code reviews, and technical decision-making Implement monitoring, logging, and observability solutions to ensure production reliability Continuously improve system scalability, performance, security, and maintainability Contribute to engineering best practices and knowledge sharing across the team

🏢 Summary: Full-time remote B2B role for a Software Engineer focused on Python backend development and implementation of Generative AI solutions for internal products. The position centers on integrating LLM-based models via APIs, building enterprise-grade microservices, and collaborating with Data Scientists in a distributed Agile team. Work involves productionizing AI models within the Azure ecosystem, with emphasis on structured, secure, and high-quality implementations. 🗂️ Requirements: Strong experience in Python backend development, Experience implementing LLM solutions via APIs, Understanding of Generative AI architectures and concepts, Experience in enterprise-scale environments, Experience building and consuming APIs, Ability to work in regulated or structured environments, English proficiency at C1 or strong B2 level 📃 Skills: Python, LLM, GenAI, APIs, RAG, Azure, AzureOpenAI, Microservices, REST, VectorDB 🏢 Description: PROJECT DETAILS: Workload: Full-time Model of working: 100% Remote Contract: B2B, long-term Rate: up to 145 PLN/h nett + VAT About the Role We are looking for a Software Engineer to work on Generative AI–based internal products developed in the company, supporting internal employees. You will join a distributed, fully remote team working on one of two AI-related business streams. The focus of the role is on Python backend development combined with implementation of Generative AI solutions , closely collaborating with Data Scientists who prepare the models. The solutions you build will be used internally within the organization. Responsibilities Design, develop, and deploy backend solutions in Python Implement Generative AI models prepared by Data Scientists into production-ready applications Wrap AI models with application logic and expose them as ready-to-use internal solutions Work mainly with API-based integrations , including LLM usage via APIs Implement and support LLM-based solutions (classic LLM usage through APIs) Work with Retrieval-Augmented Generation (RAG) concepts, including knowledge bases for language models Develop and maintain APIs and microservices Ensure solutions meet enterprise-level quality, security, and governance standards Write clean, maintainable code with appropriate test coverage Collaborate within Agile teams (PM, PO, developers, QA, architects) Participate in the full lifecycle: Business analysis Development Hypercare Further development Technology & Architecture Context Backend and GenAI work is fully Python-based GenAI models are consumed and exposed via APIs Azure OpenAI is used as part of the Azure ecosystem Strong emphasis on correct and well-structured implementation of AI models , not on model training Approximate work split: 80% backend Python development 20% GenAI/LLM solution implementation Key Requirements Strong experience in Python backend development Experience implementing solutions using LLMs via API Understanding of Generative AI architectures and basic GenAI concepts Experience with enterprise-scale environments Experience in building and consuming APIs Ability to work in regulated or structured organizational environments English: C1 or strong B2 Nice to Have Experience in regulated industries Familiarity with RAG concepts (vector databases / knowledge bases) Experience working in large enterprise organizations

🏢 Summary: Full-time remote B2B role for a Software Engineer focused on Python backend development and implementation of Generative AI solutions for internal enterprise products. The position involves integrating LLM-based models via APIs, building microservices, and deploying production-ready AI applications in an Azure-based environment. Work is primarily backend development with partial focus on GenAI/LLM integration in a distributed Agile team. 🗂️ Requirements: Strong experience in Python backend development, Experience implementing LLM solutions via APIs, Understanding of Generative AI architectures and concepts, Experience building and consuming APIs, Experience with enterprise-scale systems, Ability to work in regulated or structured environments, English proficiency at B2 or higher 📃 Skills: Python, GenAI, LLM, API, Azure, AzureOpenAI, RAG, Microservices, REST, VectorDB, Git, Agile 🏢 Description: PROJECT DETAILS: Workload: Full-time Model of working: 100% Remote Contract: B2B, long-term Rate: up to 145 PLN/h nett + VAT About the Role We are looking for a Software Engineer to work on Generative AI–based internal products developed in the company, supporting internal employees. You will join a distributed, fully remote team working on one of two AI-related business streams. The focus of the role is on Python backend development combined with implementation of Generative AI solutions , closely collaborating with Data Scientists who prepare the models. The solutions you build will be used internally within the organization. Responsibilities Design, develop, and deploy backend solutions in Python Implement Generative AI models prepared by Data Scientists into production-ready applications Wrap AI models with application logic and expose them as ready-to-use internal solutions Work mainly with API-based integrations , including LLM usage via APIs Implement and support LLM-based solutions (classic LLM usage through APIs) Work with Retrieval-Augmented Generation (RAG) concepts, including knowledge bases for language models Develop and maintain APIs and microservices Ensure solutions meet enterprise-level quality, security, and governance standards Write clean, maintainable code with appropriate test coverage Collaborate within Agile teams (PM, PO, developers, QA, architects) Participate in the full lifecycle: Business analysis Development Hypercare Further development Technology & Architecture Context Backend and GenAI work is fully Python-based GenAI models are consumed and exposed via APIs Azure OpenAI is used as part of the Azure ecosystem Strong emphasis on correct and well-structured implementation of AI models , not on model training Approximate work split: 80% backend Python development 20% GenAI/LLM solution implementation Key Requirements Strong experience in Python backend development Experience implementing solutions using LLMs via API Understanding of Generative AI architectures and basic GenAI concepts Experience with enterprise-scale environments Experience in building and consuming APIs Ability to work in regulated or structured organizational environments English: C1 or strong B2 Nice to Have Experience in regulated industries Familiarity with RAG concepts (vector databases / knowledge bases) Experience working in large enterprise organizations

🏢 Summary: Senior Python Engineer role focused on owning backend architecture, leading technical decisions, and delivering scalable high-load systems with AI-powered features such as chatbots and voice-to-text integrations. The position combines hands-on backend development with team leadership, emphasizing architecture, scalability, and production reliability. You will drive backend strategy, mentor engineers, and ensure robust AI/LLM integrations aligned with product goals. 🗂️ Requirements: 5+ years of software development experience, Strong hands-on experience with Python 3 and asynchronous programming, Experience with FastAPI or Django DRF, Experience designing microservices or modular architectures, Strong knowledge of PostgreSQL, Experience with Redis or MongoDB, Experience with vector databases, Experience with pytest and TDD/BDD principles, Experience with Docker and CI/CD pipelines, Experience with Kubernetes, Experience with AWS or GCP or Azure, Knowledge of clean code and SOLID principles, Experience with typing and type checking, Experience with scalability and production monitoring, Experience building GenAI or LLM-powered products 📃 Skills: Python, FastAPI, Django, PostgreSQL, Redis, MongoDB, Qdrant, pytest, Docker, Kubernetes, AWS, GCP, Azure, CI/CD, mypy, Pydantic, LangChain, LlamaIndex, LLaMA, Mistral, Mixtral 🏢 Description: We are looking for Senior Python Engineer to take ownership of backend architecture, technical leadership, code quality, and team development. You will work on complex backend systems, design scalable architectures, and lead a talented engineering team, collaborating closely with business stakeholders to translate requirements into robust technical solutions. You will play a key role in shaping the product roadmap, making strategic architecture decisions, and ensuring that delivery aligns with business goals. A key component of the initiative is the development of internal AI-powered capabilities, including a generic chatbot and voice-to-text features. You will provide technical leadership for AI integrations, ensuring scalable, maintainable, and performant systems. Basic German is a plus, but your expertise in strategy, technical leadership, and hands-on delivery is what matters most. Why Join Us: Lead a high-impact project with real public-sector relevance Take ownership of architecture and system design end-to-end Influence the product roadmap and technical direction Work with a talented, collaborative engineering team Contribute to AI-driven, innovative features with large-scale impact Responsibilities: Own backend architecture and technical decisions for scalable, high-load systems Lead the team in designing, implementing, and maintaining backend services and APIs Guide technical design reviews, code quality, and engineering best practices Balance hands-on development (~40–60%) with leadership and mentoring (~40–60%) Oversee scalability, performance optimization, and reliability of production systems Lead incident response, bug fixing, and production issue resolution Provide technical guidance for AI/LLM-powered features, such as chatbots and voice-to-text integration Collaborate closely with Product, Frontend, and AI/ML teams to translate requirements into technical solutions Drive adoption of observability, monitoring, and testing standards across the team Mentor and support engineers to foster team growth and knowledge sharing Must-Have Skills: 5+ years experience in Software Development Strong product mindset with experience in team organization, task prioritization, and project planning Ability to make and own technical and architectural decisions Strong problem-solving and proactive approach Excellent communication and interpersonal skills for cross-team collaboration Strong analytical and organizational abilities; able to manage dependencies, risks, and cross-team planning Hands-on experience with Python 3, including asynchronous programming Experience with backend frameworks (FastAPI, Django DRF) Experience designing and developing microservices or modular architectures Strong knowledge of relational (PostgreSQL) and NoSQL (Redis, MongoDB) databases Experience with vector storage (e.g., Qdrant) Understanding of testing strategies (pytest, TDD/BDD principles) Familiarity with Docker, CI/CD pipelines, and production deployments Strong experience with Kubernetes and cloud platforms (AWS, GCP, Azure) Knowledge of clean code principles, SOLID, typing (mypy, Pydantic) Experience with scalability, production monitoring, and incident management Experience building GenAI or LLM-powered products Nice-to-Have Skills: Experience with public-sector or government digital transformation projects Familiarity with LangChain, LlamaIndex, or similar tooling Experience with open-source LLMs (LLaMA, Mistral, Mixtral) Experience in high-growth startup environments Knowledge of cost optimization for AI inference and infrastructure Basic German language skills for team onboarding and future customer projects

🏢 Summary: Senior Backend Engineer role focused on designing, building, and maintaining production backend systems and AI-driven workflows in a fully onsite Warsaw office environment. The position involves ownership of system architecture, APIs, distributed systems, and cloud infrastructure from design through production. Candidates will collaborate across teams, improve engineering processes with AI tools, and contribute to scalable, reliable solutions. 🗂️ Requirements: Strong experience as a senior backend engineer on production systems, Excellent Python programming skills, Understanding of distributed systems, Experience with AWS or Azure cloud platforms, Knowledge of SQL and NoSQL databases, Experience with asynchronous processing and service design, Ability to design and deliver systems from idea to production, Strong written and spoken communication skills, Regular use of AI development tools, Ability to work fully onsite in Warsaw 📃 Skills: Python, AWS, Azure, SQL, NoSQL, APIs, AI, TypeScript, GitHub, Copilot, Claude, OpenAI, Codex 🏢 Description: Please note: This role requires working from our office in Warsaw city centre 5 days a week . This is a fully on-site position , and remote or hybrid work is not available . About Us Many companies want to use AI agents, but these agents often struggle with real business tasks. We solve this problem by building a platform that helps AI understand business rules, workflows, and processes. This allows AI to make better decisions and provide accurate, reliable, and compliant results. Well-known companies from different industries use our technology to automate up to 85% of customer cases, reduce handling time by 20–25%, and complete tasks that used to take hours in just seconds. We also work with leading technology partners and have been recognized for our innovative approach. Our goal is to help people everywhere get better answers through AI. Job Description We are looking for a Senior Backend Engineer who can take ownership of important systems instead of only completing assigned tasks. You will solve complex problems, design backend solutions, build them, and make sure they run well in production. We want someone with strong technical skills, good communication, and the ability to create simple, reliable, and easy-to-maintain systems. This is a product engineering role with responsibility from system design to production. The position is based in Warsaw and requires office work. Responsibilities Design and develop backend services, APIs, data processing, and background tasks for production systems. Turn unclear business needs into clear technical plans and practical solutions. Maintain services after release by improving reliability, monitoring, performance, and fixing issues. Make good decisions about system architecture, data models, interfaces, and future scaling. Write technical documentation, architecture notes, and diagrams when they help the team. Work closely with product managers, frontend engineers, and platform engineers to deliver complete solutions. Improve development processes using AI tools, automation, and internal workflows. Support the team through code reviews, design reviews, and practical technical leadership. Requirements Strong experience as a senior backend engineer working on production systems. Excellent Python skills and the ability to write clean and maintainable code. Good understanding of distributed systems, including concurrency, failure handling, data consistency, asynchronous processing, and service design. Experience with cloud platforms such as AWS, Azure, or similar services. Knowledge of SQL, NoSQL databases, schema design, and performance optimization. Ability to take a project from an idea through design and implementation to production. Strong written and spoken communication skills with the ability to explain technical topics clearly. Regular use of AI tools in everyday development and interest in improving AI-based workflows. Nice to Have Experience with LLM-based applications, search systems, AI infrastructure, or large data pipelines. Knowledge of TypeScript or the ability to contribute to frontend development when needed. Experience guiding other engineers and influencing technical decisions without being a formal manager. What We Offer B2B contract and company stock options. MacBook Pro for work. Modern technology stack and opportunities to contribute to open-source projects. Access to advanced AI development tools, including GitHub Copilot, Claude Code, OpenAI Codex, TypingMind, and MCP servers. Our Culture and Values Our leadership team has strong experience in AI and knowledge management. We have secured more than $60 million in funding and achieved three years of continuous 3x growth. Our work is based on these values: Quality – We aim for excellent work and high coding standards. Momentum – We take initiative and keep projects moving forward. Accountability – We take responsibility and give honest, respectful feedback. Hard Work – We believe great results come from teamwork and consistent effort. Learning Agility – We stay curious, learn from mistakes, and improve every day. Adapt and Thrive – We accept change and see challenges as opportunities. Win Together – We succeed as one team through honesty, openness, and support for our shared mission.

🏢 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: Senior Data Engineer role focused on building and optimizing data integration and retrieval solutions that power Generative AI systems, including AI agents and RAG pipelines. The position involves designing scalable data pipelines and Python-based microservices integrated with large-scale GenAI platforms. The engineer will contribute to architecture and ensure high performance, reliability, and security of data services. 🗂️ Requirements: 5+ years of experience in software or data engineering with strong focus on Python, Hands-on experience with FastAPI and microservices, Experience with API-driven architectures, Experience with databases or data platforms (MongoDB, PostgreSQL, Hadoop, BigQuery, Starburst or similar), Understanding of vector stores, embeddings or semantic search concepts, Experience with cloud platforms (GCP or Azure), Solid understanding of Unix/Linux environments, Strong debugging skills 📃 Skills: Python, FastAPI, Microservices, APIs, MongoDB, PostgreSQL, Hadoop, BigQuery, Starburst, GCP, Azure, Linux, Unix, Vectorstores, Embeddings, SemanticSearch, Debugging 🏢 Description: Senior Data Engineer (Python / GenAI) 📍 Location: Kraków, Poland (hybrid: 2 days in the office, 3 days remote) 📄 B2B Contract: 210 – 260 PLN / hour We are looking for a proactive Senior Data Engineer (Python / GenAI) to join an international team building advanced data integration and retrieval solutions powering Generative AI across the organization. You will work closely with Engineers, Architects and AI Specialists to design, build and optimize data flows that directly support AI agents, RAG pipelines and large‑scale GenAI applications. This role sits within a collaborative engineering environment and offers the opportunity to influence architecture, development standards and the overall quality of next‑generation AI‑driven systems. Key Responsibilities: Design and develop data integration components enabling GenAI models to access and process data from multiple internal systems. Build and maintain data transfer pipelines ensuring scalability, reliability and security. Develop Python‑based microservices (FastAPI) integrated with broader GenAI platforms. Work with vector stores, memory stores and RAG pipelines to optimize data retrieval and context generation for AI agents. Collaborate with cross‑functional teams to align data integrations with overall GenAI architecture. Implement monitoring, observability and performance tuning for data services. Participate in Agile ceremonies: sprint planning, reviews, retrospectives and daily stand‑ups. Requirements: 5+ years of experience in software or data engineering with strong focus on Python . Hands‑on experience with FastAPI , microservices and API‑driven architectures. Experience with databases and data platforms such as MongoDB, PostgreSQL, Hadoop, BigQuery, Starburst or similar. Understanding of vector stores , embeddings or semantic search concepts. Experience working with cloud platforms (GCP or Azure). Solid understanding of Unix/Linux environments. Strong debugging skills and ability to clearly communicate findings. Nice to Have: Experience with RAG pipelines , context engineering or evaluation systems. Knowledge of Google ADK or similar AI development toolkits. Experience with memory stores or caching systems. Exposure to GenAI platforms, LLM‑based solutions or AI agents. Familiarity with DevOps practices and CI/CD pipelines. What We Offer: Long‑term cooperation within a high‑impact, innovative AI programme. Real influence on architecture, engineering standards and data integration strategy. Work in a multicultural, distributed environment. Private medical care (LuxMed) and Multisport card. Stable B2B contract with competitive hourly rate. To learn more about Antal, please visit www.antal.pl