Python Developer

🏢 Summary: The offer is for a senior Integration Engineer to design and build high-performance, mission-critical integration platforms in globally distributed cloud environments. The role focuses on microservices architecture, event-driven systems, and integration between industrial (OT) and enterprise IT systems using modern technologies. You will take full ownership of solutions from design and development to testing, CI/CD, and production support. 🗂️ Requirements: Minimum 5 years of professional software development experience, Strong experience with Java ecosystem, Proven experience in designing and building microservices, Hands-on experience with messaging and event streaming systems, Experience with REST and SOAP APIs and related protocols, Knowledge of security standards OAuth2, JWT, SAML, TLS, Experience with unit and integration testing, Hands-on experience with AWS or Azure or GCP, Experience with CI/CD and containerization, English proficiency at minimum B2 level 📃 Skills: Java, Kafka, JMS, MQTT, AMQP, REST, SOAP, OData, GraphQL, gRPC, JSON, XML, OAuth2, JWT, SAML, TLS, AWS, Azure, GCP, CI/CD, Docker, Kubernetes, HiveMQ, HighByte 🏢 Description: C&F is a technology services company providing innovative solutions in Data Management, Big Data, Advanced Analytics and Compliance . With a highly integrated team of 400+ experts , for over 20 years C&F has been delivering superior engineering and premium operations to Fortune 500 companies, primarily in the Life Science industry. 🌍 We build and run the core data platforms for global companies . Our team designs high-performance, resilient systems that solve complex challenges in Enterprise Integration, and the Industrial Internet of Things (IIoT). We are looking for a top-tier Integration Engineer, a key technical expert to join our team and help us build these mission-critical, globally distributed solutions. This is a chance to work on challenging projects at a global scale, using modern technology without the burden of legacy code. 📝 You will be responsible for: Designing and building high-performance, mission-critical integration platforms using modern programming languages Building and operating globally distributed systems designed for High Availability across AWS, Azure, and GCP Designing and developing solutions based on a microservices architecture Integrating industrial systems (OT) with enterprise IT, using platforms like HiveMQ and HighByt e alongside event-streaming technologies like Kafka Taking full ownership of your work—from design and coding to automated testing, CI/CD, and production support 👉 What you will need: At least 5 years of professional experience in software development plus a hands-on approach to owning and delivering complete solutions Strong experience with the Java ecosystem Proven experience designing and building microservices Experience with messaging & event streaming: Kafka, Azure Event Hub, JMS, MQTT, AMQP Experience with APIs & protocols: REST, SOAP, OData, GraphQL, gRPC, JSON, XML, Kafka, MQTT Experience with Security standards: OAuth2, JWT, SAML, TLS and API management Demonstrated expertise in writing comprehensive unit and integration tests ; you believe in and practice a culture of high code coverage Hands-on experience with at least one major cloud platform (AWS, Azure, or GCP) Solid experience with DevOps practices, including CI/CD and containerization Very good command of English (level B2 is a must) Nice to have: Experience with IoT data integration and building UNS Familiarity with IoT protocols (MQTT, OPC-UA) and IoT platforms (HighByte Intelligence Hub, Ignition, Litmus, Node Red) Experience in Python An interest in AI/ML and its applications in enterprise data Strong understanding of Agile methodologies Strong communication and presentation skills are important, along with the ability to build rapport and credibility with stakeholders ✨ What we offer: You choose your employment type – we’re open to both employment contracts and B2B arrangements. Learning & development opportunities – after your probation period, you’ll have access to a highly flexible and generous English language reimbursement program, along with an individual development budget to use as you see fit. Classic benefits like private medical care, a sports card, and a preferential life insurance plan. Plus, our infamous Fruit Tuesdays and a special summer bonus – ice cream. A hybrid work setup with plenty of flexibility. Delivery teams work mostly remotely. Support teams come to the office at least once a week – as an HR team, we meet every Wednesday. On other days, you decide where you work. A bunch of non-work activities , including Office Day (a fun-filled day when employees from all over Poland gather at the office), POP UP integrations,  various competitions from cooking to photography, and the chance to submit charity causes to our CF4GOOD program, which provides support to those in need. A workplace that values people and is built on collaboration, not competition. If you’re tired of toxic work environments, you’ll finally get a chance to breathe. And if you’ve been lucky with great employers so far, we’ll do our best to keep that streak going.

🏢 Summary: The offer is for a Software Architect specializing in Python and LLM-powered systems to design and lead the delivery of scalable AI solutions using RAG architectures and agent-based workflows. The role combines hands-on backend engineering with architectural ownership, covering system design, cloud infrastructure, and DevOps practices. The candidate will lead technical direction, ensure high-quality standards, and build end-to-end AI-driven platforms. 🗂️ Requirements: Proven experience in software architecture design (modular monolith, microservices, event-driven systems), Strong expertise in Python 3.11+ with async programming, Experience designing and building LLM-powered systems and RAG architectures, Hands-on experience with FastAPI framework, Experience implementing agent-based workflows (LangGraph), Experience with REST or gRPC API design, Knowledge of Domain-Driven Design and clean architecture principles, Experience with PostgreSQL and SQLModel, Experience with Redis for caching and session management, Experience with CI/CD pipelines, Experience with Docker and Kubernetes, Experience with at least one cloud platform (Azure preferred), Experience with Infrastructure as Code (Terraform preferred), Experience with observability tools (OpenTelemetry), Experience leading development teams and conducting code reviews 📃 Skills: Python, FastAPI, LangGraph, Azure, AzureOpenAI, Anthropic, VertexAI, ChromaDB, SQLModel, PostgreSQL, Redis, GitHubActions, Docker, Kubernetes, Terraform, OpenTelemetry, Pandas, PySpark, NumPy, scikitlearn, gRPC, REST, GraphQL 🏢 Description: C&F is a technology services company providing innovative solutions in Data Management, Big Data, Advanced Analytics and Compliance . With a highly integrated team of 400+ experts , for over 20 years C&F has been delivering superior engineering and premium operations to Fortune 500 companies, primarily in the Life Science industry. 🌍 We are seeking highly skilled Software Architect with strong Python expertise specializing in LLM powered systems, RAG architectures, and agent based workflows, experienced in designing end to end solutions, leading development teams, and owning technical delivery for complex projects. A perfect candidate combines hands on engineering ability with architectural thinking, ensuring high quality software design, scalable systems, and efficient collaboration with stakeholders. They are comfortable working across backend services, data pipelines, cloud platforms, and modern DevOps toolchains. 📝 What you will do: Architecture & Delivery Design system architecture using FastAPI, LangGraph, and Azure OpenAI Own high-level design, API specs, module decomposition Lead technical planning, estimations, sprint planning Ensure compliance with coding standards, security, CI/CD in AI/LLM Solution Development Build complex agentic workflows (LangGraph) Implement RAG pipelines backed by ChromaDB Optimize prompts, embeddings, context, memory, retrieval Integrate multiple LLM providers (Azure OAI, Anthropic, Vertex AI) Backend Engineering Develop backend services using Python 3.11+, FastAPI, async patterns Implement data models with SQLModel + PostgreSQL Design caching, throttling, session layers using Redis DevOps & Operations Oversee CI/CD with GitHub Actions Ensure containerization best practices Implement OpenTelemetry and observability dashboards Team Leadership Conduct code reviews and mentor developers Communicate architectural decisions clearly Collaborate with product owners, UX, data scientists Maintain project documentation (MkDocs) 👉 What you will need: Software Architecture Software architecture expertise Architecture design (modular monolith, microservices, event-driven systems) Ownership of technical direction, backlog, and quality standards API design (REST, gRPC; GraphQL is optional) Domain-Driven Design and clean architecture principles System decomposition and technical roadmap planning Python Engineering Advanced Python (asyncio, type hints, packaging, testing, profiling) Frameworks: FastAPI Data and processing pipelines: Pandas, PySpark (optional) ML/analytics exposure (NumPy, scikit-learn, MLOps basics — optional but valuable) Cloud (experience with one or more) Azure: Functions, App Services, AKS, Event Hub, Cosmos DB DevOps & Tooling CI/CD (GitHub Actions, Azure DevOps) Docker, Kubernetes Infrastructure as Code (Terraform preferred) Observability (OpenTelemetry) Team Leadership Leading cross-functional development teams (3–12 engineers) Conducting code reviews and architecture reviews, mentoring engineers Translating business requirements into technical design Managing delivery risks, estimations, and sprint planning ✨ What we offer: You choose your employment type – we’re open to both employment contracts and B2B arrangements. Learning & development opportunities – after your probation period, you’ll have access to a highly flexible and generous English language reimbursement program, along with an individual development budget to use as you see fit. Classic benefits like private medical care, a sports card, and a preferential life insurance plan. Plus, our infamous Fruit Tuesdays and a special summer bonus – ice cream. A hybrid work setup with plenty of flexibility. Delivery teams work mostly remotely. Support teams come to the office at least once a week – as an HR team, we meet every Wednesday. On other days, you decide where you work. A bunch of non-work activities , including Office Day (a fun-filled day when employees from all over Poland gather at the office), POP UP integrations,  various competitions from cooking to photography, and the chance to submit charity causes to our CF4GOOD program, which provides support to those in need. A workplace that values people and is built on collaboration, not competition. If you’re tired of toxic work environments, you’ll finally get a chance to breathe. And if you’ve been lucky with great employers so far, we’ll do our best to keep that streak going

🏢 Summary: Development and maintenance of dynamic web applications using Python and Django for a leading German telecommunications and IT distributor. The role focuses on building server-side rendered applications with modern frontend styling and seamless UX, while ensuring high quality through CI/CD and monitoring practices. You will collaborate closely with design and backend to deliver scalable, production-ready solutions. 🗂️ Requirements: Proficiency in Python, Strong knowledge of Django framework internals, Experience with HTMX, Proficiency in HTML, Proficiency in CSS, Experience with SSR, Good knowledge of Tailwind CSS, Experience with PostgreSQL or other relational databases, Experience with CI/CD pipelines, Experience with CircleCI, Knowledge of Sentry, Ability to develop and maintain dynamic web applications using Django 📃 Skills: Python, Django, HTMX, HTML, CSS, Tailwind, PostgreSQL, CircleCI, Sentry, SSR, CICD 🏢 Description: We are an AI-native data and technology partner for private capital and healthcare. Founded in 2010 and headquartered in Warsaw, we work with leading PE firms, VC funds, and healthcare organizations to build proprietary data infrastructure, deploy AI solutions, and drive AI-native transformation. Our clients manage a cumulative $210B+ in assets. Our average engagement runs five years. Our NPS sits above 80. We don't need to claim credibility — we can show it. We've also done to ourselves what we now do for clients. We've restructured our own company around AI — tools, policies, roles, delivery models. This isn't a pitch. It's a playbook we've already run, and we're hiring the engineers who will run it for others. The Project: Our client is one of the leading players in the German telecommunications and IT distribution market. With a broad portfolio of products and strong partnerships with major network operators, the company has built a reputation for reliability, innovation, and outstanding service. Recognized multiple times by industry leaders, they continue to grow by embracing new technologies and delivering top-tier solutions to a wide range of business partners. The ideal candidate will be well-organized, eager to learn and adapt, and driven to tackle complex challenges. Most importantly, you’ll thrive in a collaborative, team-oriented environment! Your Responsibilities: Co-develop and co-maintain web applications using Python and Django Crafting beautiful UI and styling the web application using Tailwind CSS Develop and maintain dynamic web applications using HTMX with the Django framework Implementing and integrating more compound web components Ensure consistent application of UX best practices to deliver intuitive and user-centered interfaces Close collaboration with the team (Designer and Backend Engineer) to make sure implementation meets requirements Implement CI/CD pipelines using CircleCI Monitor and debug issues using Sentry Attention to detail and sense of aesthetics, from clean code to beautiful UI Required Skills & Experience: Proficiency in HTML, and CSS and SSR Good knowledge of Tailwind CSS Good understanding of Django framework internals Proficiency in Python Experience with HTMX Experience with PostgreSQL or other relational databases Experience working with CI/CD pipelines (CircleCI) Knowledge of Sentry for monitoring and debugging Problem-solving mindset, ability to work both independently and within a team Excellent command in spoken and written English, at least C1 Nice to Have: Advanced knowledge of Docker and daily hands-on experience SQL proficiency for debugging and performance optimization Basic knowledge of Agile/Scrum methodology What We Offer: Work with a talented team redefining the global perception of Poland Flexible working hours and remote work options Comfortable office in central Warsaw with all essential tools (MacBook, external monitor, ergonomic chairs) Fully equipped kitchen with fresh fruit, hot & cold beverages Multisport card & private medical care A culture of feedback – evaluation meetings, mentoring, and career growth opportunities Support for continuous learning – we encourage and invest in the professional development of our engineers Sounds like a perfect place for you? Don’t hesitate to click apply and submit your application today!

🏢 Summary: Senior Python Engineer role focused on designing and developing GenAI applications, including architecture, backend services, and AI integrations. The position involves building and maintaining APIs and microservices, integrating GenAI models (e.g., RAG, agentic workflows), and ensuring high-quality, well-tested solutions in cloud environments. The role requires close collaboration across the full project lifecycle while driving technical excellence in AI-powered systems. 🗂️ Requirements: 6+ years of experience in Python development, Fluency in Python ecosystem, Experience with FastAPI or Flask, Experience with SQL and NoSQL databases, Knowledge of clean code and design patterns in Python, Experience writing unit tests, Experience integrating GenAI models into business applications, Knowledge of RAG and agentic workflows, Experience building APIs and microservices, Familiarity with AWS, GCP, or Azure, Familiarity with Continuous Deployment, English C1, Polish C1 📃 Skills: Python, FastAPI, Flask, SQL, NoSQL, GenAI, RAG, APIs, Microservices, AWS, GCP, Azure, CI/CD, UnitTesting 🏢 Description: 🚀 You will be responsible for: Design architecture of GenAI applications, Design, develop, and maintain Python code in AI applications and components, Code review and identification of areas of improvments, Collaborate with data scientists and machine learning engineers to utilize AI models in the applications, Knowledge of basic types of solutions using GenAI models (RAGs, agentic workflows, etc.) Collaborate with other roles (managers, testers, DevOps, etc.) through the whole life cycle of a project, Develop and maintain APIs and microservices for AI integration with other systems, Conduct experiments and evaluations to measure the performance of GenAI models, Stay up-to-date with the latest advancements in GenAI technologies, Contribute to a collaborative and innovative team culture. Additional advantages, but not required directly for the position: Knowledge of another object-oriented programming language (Java/C#/C++) Knowledge of Machine Learning algorithms and libraries (scikit-learn, PyTorch) 👉 What you will need: At least 6 years of experience and fluency in Python development ecosystem, Experience in building back-end services in Python with frameworks like FastAPI (or Flask ), SQL and NoSQL databases , Knowledge of clean code and design patterns in Python , strong attitude to build well structured, high quality solutions, Experience in writing robust unit tests for developed applications, Experience in using GenAI models in building business applications, Familiarity with cloud platforms (AWS, GCP, Azure) and cloud-native technologies, Familiarity with Continuous Deployment lifecycle, Excellent problem-solving and analytical skills, Ability to work independently and as part of a team, Very good knowledge of English (C1) and Polish (C1) Strong communication and documentation skills 👉 What we offer: The opportunity to work on cutting-edge projects in the dynamic field of cloud and data technologies. A supportive and collaborative work environment that fosters professional growth . Competitive remuneration and various bonuses, such as access to private medical care ( Medicover or Luxmed ) and sport ( Multisport ) cards, reimbursement for English classes , access to the Employee Capital Plan ( PPK ) and b udget for professional development. We mostly work remotely , but we ask that you be willing to come to the office occasionally for workshops, client meetings or project-related discussions. Non-work-related activities galore! We have a running team (with a pro coach), internal competitions, from cookery to photography, a ping-pong league, team building, well-being expert seminars. You can suggest beneficiaries for our CF4GOOD charity program . Company culture rooted in respect and cooperation, not competition . You'll be working with great people, open to new challenges and directions. If you are tired of the proverbial corporate treadmill, come to us to rest mentally. If you've had luck with employers, we'll do our best not to buck the trend.

🏢 Summary: Senior-level role focused on designing and leading high-performance, scalable frontend and full-stack solutions for global ad delivery and tracking systems. The position emphasizes web performance optimization, observability (RUM and Synthetic), and architectural excellence across performance-critical features. You will drive measurable improvements in user metrics while maintaining top coding standards and technical leadership. 🗂️ Requirements: 8+ years of hands-on software engineering experience, Strong understanding of frontend development and internal mechanisms, Proven experience in web performance optimization and advanced loading strategies, Proficiency in JavaScript and TypeScript, Experience with modern frontend frameworks (React), Experience with build tools (Webpack or Vite), Knowledge of Internet protocols and technologies (DNS, HTTP, cookies), Experience monitoring and analyzing production systems, Understanding of full-stack concepts and backend APIs (Node.js, Python, or Java), Experience with deployment and CI/CD pipelines 📃 Skills: JavaScript, TypeScript, React, Node.js, Python, Java, Webpack, Vite, DNS, HTTP, Cookies, RUM, Synthetic, CICD, Caching, Monitoring 🏢 Description: You will: Design and lead implementation of system changes that deliver high performance, scalability and observability for displaying and tracking ads world wide. Develop tools and optimizations to drive measurable improvements in critical user performance metrics. Implement and maintain high-quality frontend and full-stack solutions for displaying Ads globally, focusing on extreme performance and scalability. Develop monitoring systems (RUM and Synthetic) to track crucial metrics like reliability or viewability and use data to diagnose and resolve performance bottlenecks. Collaborate closely with Ads Layouts specialists and backend engineers to ensure smooth data flow and optimal architectural alignment for performance-critical features. Write, test, and deploy robust, efficient, and well-documented code in JavaScript/TypeScript/Python/Java, ensuring adherence to the highest coding and performance standards. Provide hands-on technical leadership: solving complex system challenges, participating in planning and scoping of projects, and ensuring the implementation of the highest coding standards through participation in code reviews. Requirements: 8+ years of hands-on experience in software engineering, including the understanding of Frontend Development and its internal mechanisms. Practical experience and strong understanding of Web Performance optimization techniques and advanced loading strategies (caching, asset delivery). Solid proficiency in JavaScript/TypeScript and modern frameworks like e.g., React. Experience with relevant build tooling (e.g., Webpack, Vite). Very good knowledge of fundamental Internet protocols and technologies (DNS, HTTP, cookies and others). Practical ability to observe, monitor and analyse the operation of production systems (and draw valuable conclusions from it). Good understanding of full-stack concepts, including working with backend APIs (Node.js, Python, or Java) and deployment/CI/CD pipelines. C1 level in English and Polish. Nice to have: Experience in the AdTech/Real Time Bidding space. Experience contributing to Real User Monitoring (RUM) systems. Selected technologies used: You will be working within a modern stack that includes JavaScript/TypeScript, React, Node.js, Python, and Java. We Offer: Projects focused on extreme performance and high code quality – solid code reviews are our standard. Collaboration within an interdisciplinary, self-sufficient team (including DevOps, database experts, backend developers, product designers, and QA engineers). Hardware and software tailored to your preferences (e.g., MacBook, AI tool licenses). Flexible working conditions – no core hours, fully remote cooperation possible. Apply now! You don't need to tick every box to apply. If you are passionate about software engineering or web performance, send us your CV, and we'll review it.

🏢 Summary: Lead the design and implementation of high-performance, scalable frontend and full-stack solutions for globally distributed ad systems, with a strong focus on web performance and observability. The role involves optimizing critical user metrics, building monitoring systems, and ensuring robust architecture and code quality across performance-sensitive features. 🗂️ Requirements: 8+ years of hands-on software engineering experience, Strong expertise in frontend development and internal browser mechanisms, Proven experience in web performance optimization and advanced loading strategies, Proficiency in JavaScript and TypeScript, Experience with modern frontend frameworks such as React, Experience with build tools such as Webpack or Vite, Solid understanding of Internet protocols including DNS and HTTP, Ability to monitor, analyze, and diagnose production system performance, Understanding of full-stack concepts and backend API integration, Experience with CI/CD pipelines 📃 Skills: JavaScript, TypeScript, React, Node.js, Python, Java, Webpack, Vite, DNS, HTTP, RUM, CICD, Caching 🏢 Description: You will: Design and lead implementation of system changes that deliver high performance, scalability and observability for displaying and tracking ads world wide. Develop tools and optimizations to drive measurable improvements in critical user performance metrics. Implement and maintain high-quality frontend and full-stack solutions for displaying Ads globally, focusing on extreme performance and scalability. Develop monitoring systems (RUM and Synthetic) to track crucial metrics like reliability or viewability and use data to diagnose and resolve performance bottlenecks. Collaborate closely with Ads Layouts specialists and backend engineers to ensure smooth data flow and optimal architectural alignment for performance-critical features. Write, test, and deploy robust, efficient, and well-documented code in JavaScript/TypeScript/Python/Java, ensuring adherence to the highest coding and performance standards. Provide hands-on technical leadership: solving complex system challenges, participating in planning and scoping of projects, and ensuring the implementation of the highest coding standards through participation in code reviews. Requirements: 8+ years of hands-on experience in software engineering, including the understanding of Frontend Development and its internal mechanisms. Practical experience and strong understanding of Web Performance optimization techniques and advanced loading strategies (caching, asset delivery). Solid proficiency in JavaScript/TypeScript and modern frameworks like e.g., React. Experience with relevant build tooling (e.g., Webpack, Vite). Very good knowledge of fundamental Internet protocols and technologies (DNS, HTTP, cookies and others). Practical ability to observe, monitor and analyse the operation of production systems (and draw valuable conclusions from it). Good understanding of full-stack concepts, including working with backend APIs (Node.js, Python, or Java) and deployment/CI/CD pipelines. C1 level in English and Polish. Nice to have: Experience in the AdTech/Real Time Bidding space. Experience contributing to Real User Monitoring (RUM) systems. Selected technologies used: You will be working within a modern stack that includes JavaScript/TypeScript, React, Node.js, Python, and Java. We Offer: Projects focused on extreme performance and high code quality – solid code reviews are our standard. Collaboration within an interdisciplinary, self-sufficient team (including DevOps, database experts, backend developers, product designers, and QA engineers). Hardware and software tailored to your preferences (e.g., MacBook, AI tool licenses). Flexible working conditions – no core hours, fully remote cooperation possible. Apply now! You don't need to tick every box to apply. If you are passionate about software engineering or web performance, send us your CV, and we'll review it.

🏢 Summary: Senior engineer role focused on designing and implementing high‑performance, scalable frontend and full‑stack solutions for global ad delivery systems. The position emphasizes web performance optimization, observability, and monitoring (RUM and Synthetic) to improve critical user metrics. You will lead technical initiatives, build performance‑critical features, and ensure high code quality across JavaScript/TypeScript-based systems. 🗂️ Requirements: 8+ years of hands-on software engineering experience, Strong understanding of frontend development and internal browser mechanisms, Practical experience with web performance optimization techniques, Proficiency in JavaScript and TypeScript, Experience with modern frontend frameworks (React), Experience with build tools (Webpack or Vite), Knowledge of Internet protocols (DNS, HTTP, cookies), Experience monitoring and analyzing production systems, Understanding of full-stack architecture and backend APIs (Node.js, Python, or Java), Experience with CI/CD pipelines 📃 Skills: JavaScript, TypeScript, React, Node.js, Python, Java, Webpack, Vite, DNS, HTTP, cookies, CI/CD, RUM, Synthetic, caching, observability, APIs 🏢 Description: You will: Design and lead implementation of system changes that deliver high performance, scalability and observability for displaying and tracking ads world wide. Develop tools and optimizations to drive measurable improvements in critical user performance metrics. Implement and maintain high-quality frontend and full-stack solutions for displaying Ads globally, focusing on extreme performance and scalability. Develop monitoring systems (RUM and Synthetic) to track crucial metrics like reliability or viewability and use data to diagnose and resolve performance bottlenecks. Collaborate closely with Ads Layouts specialists and backend engineers to ensure smooth data flow and optimal architectural alignment for performance-critical features. Write, test, and deploy robust, efficient, and well-documented code in JavaScript/TypeScript/Python/Java, ensuring adherence to the highest coding and performance standards. Provide hands-on technical leadership: solving complex system challenges, participating in planning and scoping of projects, and ensuring the implementation of the highest coding standards through participation in code reviews. Requirements: 8+ years of hands-on experience in software engineering, including the understanding of Frontend Development and its internal mechanisms. Practical experience and strong understanding of Web Performance optimization techniques and advanced loading strategies (caching, asset delivery). Solid proficiency in JavaScript/TypeScript and modern frameworks like e.g., React. Experience with relevant build tooling (e.g., Webpack, Vite). Very good knowledge of fundamental Internet protocols and technologies (DNS, HTTP, cookies and others). Practical ability to observe, monitor and analyse the operation of production systems (and draw valuable conclusions from it). Good understanding of full-stack concepts, including working with backend APIs (Node.js, Python, or Java) and deployment/CI/CD pipelines. C1 level in English and Polish. Nice to have: Experience in the AdTech/Real Time Bidding space. Experience contributing to Real User Monitoring (RUM) systems. Selected technologies used: You will be working within a modern stack that includes JavaScript/TypeScript, React, Node.js, Python, and Java. We Offer: Projects focused on extreme performance and high code quality – solid code reviews are our standard. Collaboration within an interdisciplinary, self-sufficient team (including DevOps, database experts, backend developers, product designers, and QA engineers). Hardware and software tailored to your preferences (e.g., MacBook, AI tool licenses). Flexible working conditions – no core hours, fully remote cooperation possible. Apply now! You don't need to tick every box to apply. If you are passionate about software engineering or web performance, send us your CV, and we'll review it.

🏢 Summary: Backend engineering role focused on building scalable backend services, APIs, and internal developer platforms in a fully remote environment. The position involves improving system architecture, optimizing distributed systems, and collaborating across the full software development lifecycle. The offer includes influence on technical decisions, modern technologies, and growth opportunities within an experienced engineering team. 🗂️ Requirements: 5+ years of backend software development experience, Proficiency in PHP or experience with Java, Python, Go, Knowledge of RESTful APIs and GraphQL, Experience building scalable distributed backend systems, Experience with SQL/MySQL and database optimization, Experience with automated testing and monitoring, Knowledge of debugging production systems, Familiarity with contract-driven development, English for daily technical communication 📃 Skills: PHP, Java, Python, Go, REST, GraphQL, SQL, MySQL, React, API 🏢 Description: ✅ Your responsibilities: ・Design, develop, and maintain scalable backend services and APIs for third-party integrations. Improve platform architecture, service communication, and internal developer tooling. Collaborate with Product Managers, Designers, and Engineers throughout the entire software development lifecycle. Optimize existing systems for performance, scalability, reliability, and maintainability. Drive engineering best practices, including code quality, testing, and documentation. Participate in architecture discussions and technical decision-making. Mentor engineers through code reviews, pair programming, and knowledge sharing. Continuously improve the developer experience by building reliable internal platforms and tools. 🧠 Our requirements: 5+ years of experience in backend software development. Strong proficiency in PHP (preferred) or solid experience with Java, Python, Go , or similar backend technologies. Strong understanding of RESTful APIs , GraphQL , and API design best practices. Experience designing and building scalable, distributed backend systems. Hands-on experience with SQL/MySQL databases and database optimization. Experience with automated testing, observability, monitoring, and debugging production systems. Familiarity with contract-driven development and modern software development practices. Basic knowledge of frontend technologies such as React is a plus. Strong communication skills and the ability to collaborate across cross-functional teams. Passion for writing clean, maintainable, and high-quality code or AI automation English at a level allowing daily technical communication 🌟 What we offer: 100% remote work. Private healthcare and Multisport. Life insurance. Real influence on technical decisions and system architecture. Opportunity to build scalable backend services and developer platforms. Work with modern technologies in a collaborative engineering environment. Knowledge sharing, mentorship, and professional growth opportunities. Friendly, supportive, and experienced engineering team.

🏢 Summary: Design and lead the implementation of high-performance, scalable and observable systems for global ad serving and tracking. The role focuses on building and optimizing HTTP/gRPC services and batch jobs in Java and Python, ensuring production reliability and measurable performance improvements. You will provide hands-on technical leadership while maintaining high engineering and code quality standards. 🗂️ Requirements: Strong knowledge of Java and Python, Experience building and maintaining HTTP and gRPC services, Experience with batch processing systems, Understanding of distributed systems and concurrency, Knowledge of Internet protocols (DNS, HTTP, cookies), Ability to design for high scalability and high availability, Experience monitoring and analyzing production systems, Ability to optimize system performance at scale, Experience deploying and maintaining production environments, Understanding of complex systems from hardware to algorithms 📃 Skills: Java, Python, HTTP, gRPC, DNS, Aerospike, Memcached, GCP, BigQuery, MinIO, Kafka, Clickhouse, PostgreSQL, Elasticsearch, Kubernetes, Prometheus, Jenkins, Graphite, Concurrency, DistributedSystems, Scalability, Availability, Monitoring, Performance 🏢 Description: You will: Design and lead implementation of system changes that deliver high performance, scalability and observability for displaying and tracking ads world wide. Develop tools and optimizations to drive measurable improvements in critical user performance metrics. Implement, test, deploy, monitor and maintain (in all aspects, including setting up environment, writing configuration code, monitor production) HTTP / gRPC services and batch jobs in Java and Python, ensuring adherence to the high engineering standards. Provide hands-on technical leadership: solving complex system challenges, participating in planning and scoping of projects, and ensuring the implementation of the highest coding standards through participation in code reviews. Desired experience: Excellent understanding of how complex IT systems work - from the hardware level, through software, to algorithms. Very good knowledge of fundamental Internet protocols and technologies (DNS, HTTP, cookies and others). Good knowledge of basic methods of creating concurrent programs and distributed systems (from thread level to geo-distributed clusters level). Practical ability to observe, monitor and analyse the operation of production systems (and draw valuable conclusions from it). The ability to critically analyze the solutions created in terms of performance (from estimating the theoretical performance of the designed systems to detecting and removing actual performance problems in production). General knowledge of issues (typical problems and methods of solving them) in the areas of 'high scalability' and 'high availability'. C1 level in English and Polish. Nice to have: Experience in the AdTech/Real Time Bidding space. Experience contributing to Real User Monitoring (RUM) systems. Selected technologies used: Java, Python Aerospike, Memcached Google Cloud Platform, BigQuery, MinIO Kafka, Clickhouse PostgreSQL Elasticsearch Kubernetes, Prometheus Jenkins, Graphite We Offer: Projects focused on extreme performance and high code quality – solid code reviews are our standard. Collaboration within an interdisciplinary, self-sufficient team (including DevOps, database experts, backend developers, product designers, and QA engineers). Hardware and software tailored to your preferences (e.g., MacBook, AI tool licenses). Flexible working conditions – no core hours, fully remote cooperation possible. Apply now! You don't need to tick every box to apply. If you are passionate about software engineering, send us your CV, and we'll review it.

🏢 Summary: Design and lead the implementation of highly scalable, high‑performance ad serving and tracking systems, building and optimizing HTTP/gRPC services and batch jobs in Java and Python. The role combines hands-on development with technical leadership, focusing on observability, reliability, and measurable performance improvements in distributed production environments. You will work on globally distributed systems handling large-scale traffic with strong engineering and code quality standards. 🗂️ Requirements: Experience designing and implementing high-performance, scalable distributed systems, Strong knowledge of Java and Python, Experience building and maintaining HTTP and gRPC services, Understanding of Internet protocols (DNS, HTTP, cookies), Knowledge of concurrency and distributed systems concepts, Ability to monitor, analyze and optimize production systems, Experience with high scalability and high availability architectures, Fluent English and Polish (C1) 📃 Skills: Java, Python, HTTP, gRPC, DNS, Aerospike, Memcached, GCP, BigQuery, MinIO, Kafka, Clickhouse, PostgreSQL, Elasticsearch, Kubernetes, Prometheus, Jenkins, Graphite 🏢 Description: You will: Design and lead implementation of system changes that deliver high performance, scalability and observability for displaying and tracking ads world wide. Develop tools and optimizations to drive measurable improvements in critical user performance metrics. Implement, test, deploy, monitor and maintain (in all aspects, including setting up environment, writing configuration code, monitor production) HTTP / gRPC services and batch jobs in Java and Python, ensuring adherence to the high engineering standards. Provide hands-on technical leadership: solving complex system challenges, participating in planning and scoping of projects, and ensuring the implementation of the highest coding standards through participation in code reviews. Desired experience: Excellent understanding of how complex IT systems work - from the hardware level, through software, to algorithms. Very good knowledge of fundamental Internet protocols and technologies (DNS, HTTP, cookies and others). Good knowledge of basic methods of creating concurrent programs and distributed systems (from thread level to geo-distributed clusters level). Practical ability to observe, monitor and analyse the operation of production systems (and draw valuable conclusions from it). The ability to critically analyze the solutions created in terms of performance (from estimating the theoretical performance of the designed systems to detecting and removing actual performance problems in production). General knowledge of issues (typical problems and methods of solving them) in the areas of 'high scalability' and 'high availability'. C1 level in English and Polish. Nice to have: Experience in the AdTech/Real Time Bidding space. Experience contributing to Real User Monitoring (RUM) systems. Selected technologies used: Java, Python Aerospike, Memcached Google Cloud Platform, BigQuery, MinIO Kafka, Clickhouse PostgreSQL Elasticsearch Kubernetes, Prometheus Jenkins, Graphite We Offer: Projects focused on extreme performance and high code quality – solid code reviews are our standard. Collaboration within an interdisciplinary, self-sufficient team (including DevOps, database experts, backend developers, product designers, and QA engineers). Hardware and software tailored to your preferences (e.g., MacBook, AI tool licenses). Flexible working conditions – no core hours, fully remote cooperation possible. Apply now! You don't need to tick every box to apply. If you are passionate about software engineering, send us your CV, and we'll review it.