Backend Developer Mid / Mid+

🏢 Summary: Backend Developer role focused on designing and building scalable, cloud-based applications using Java and Spring Boot in a microservices architecture. The position involves developing and deploying distributed, event-driven services on Azure using modern containerization and API technologies. The offer emphasizes building reliable, high-quality backend systems with up-to-date cloud-native practices. 🗂️ Requirements: Strong Java development experience, Experience with Spring Boot, Experience with microservices architecture, Experience with cloud-native applications, Familiarity with Azure, Knowledge of Kafka or similar messaging systems, Understanding of GraphQL or REST APIs, Experience with Docker, Experience with Kubernetes 📃 Skills: Java, Spring, SpringBoot, Microservices, Azure, Kafka, GraphQL, REST, Docker, Kubernetes 🏢 Description: We are seeking a talented Backend Developer to join our team, contributing to the design and development of modern, cloud-based applications. The role focuses on building scalable and maintainable services using up-to-date technologies and best practices. Key Responsibilities: Develop and maintain backend services using Java and Spring Boot . Build and support microservices solutions for distributed systems. Work with cloud platforms such as Azure , including event-driven architectures. Implement and consume APIs using GraphQL or REST. Package and deploy applications using Docker and Kubernetes . Collaborate with team members to deliver reliable, high-quality software. Required Skills & Experience: Strong background in Java development with Spring Boot . Experience with microservices and cloud-native applications. Familiarity with Azure , Kafka , or similar messaging/event systems. Understanding of API design ( GraphQL /REST). Practical experience with containerization ( Docker , Kubernetes ). Nice to Have: Knowledge of CI/CD practices and automated deployments. Experience with monitoring, logging, or observability in distributed systems.

🏢 Summary: B2B opportunity for an experienced .NET Back-End Developer to build modern, scalable cloud-based solutions using C# and Azure. The role focuses on designing high-performance services, working with CosmosDB, and collaborating in an Agile team with exposure to AI-assisted development tools. This is a fully remote position with competitive hourly rates and long-term cooperation. 🗂️ Requirements: 5+ years of professional experience in .NET development, Strong experience with C#, Proven experience with Azure services, Experience with CosmosDB, Experience with TypeScript or JavaScript, Bachelor’s degree in Computer Science or related field, Ability to align with US-based team working hours, English language proficiency 📃 Skills: .NET, C#, Azure, CosmosDB, TypeScript, JavaScript, AI, Playwright, Selenium, Drupal 🏢 Description: For our client from the technology and industrial solutions sector, we are looking for a .NET Back-End Developer to join a talented development team working on modern, scalable software solutions. Responsibilities: Design, develop, and maintain high-performance back-end services using .NET and C#. Work extensively with Azure cloud services and CosmosDB to build scalable and resilient solutions. Collaborate with front-end developers, product owners, and other team members to integrate back-end services. Participate in code reviews, architectural discussions, sprint planning, and other Agile ceremonies. Use modern development tools and practices to improve productivity, code quality, and maintainability. Explore and apply AI-assisted tools where appropriate to support development, documentation, troubleshooting, and workflow efficiency. Contribute to improving development processes, engineering practices, and team knowledge sharing. Be a proactive problem-solver and continuous learner, staying current with relevant technologies and industry trends. Requirements: Application Development Experience: 5+ years of professional experience in .NET development. Cloud Development Expertise: Proven experience with C#, Azure services, and CosmosDB. Scripting / Front-End Knowledge: Experience with TypeScript preferred, or JavaScript. AI Tool Familiarity: Interest in or hands-on experience using AI tools to support software development, productivity, documentation, research, or troubleshooting. Educational Background: Bachelor’s degree in Computer Science or a related field. Flexibility: Ability to align somewhat with US-based team working hours. Communication: English language proficiency. Stack: Cloud: Azure, CosmosDB Back-End: .NET, C# Scripting / Tooling: TypeScript preferred, JavaScript acceptable Productivity / AI Tools: Familiarity with AI-assisted development or productivity tools is a plus Nice to have: Domain Knowledge: Background in Electrical Engineering or a related technical field. Background or interest in analog and mixed-signal hardware design. Knowledge of hardware or system simulation concepts. CMS Knowledge: Familiarity with Drupal. Test Automation Exposure: Familiarity with tools like Playwright or Selenium. Quality Mindset: Prior QA experience or understanding of QA methodologies is welcome. Offer: Cooperation based on a B2B contract and rate: 140-170 PLN/hour 100% remote work The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, Multisport card). About Speedapp At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch.

🏢 Summary: The role involves developing and maintaining high-performance backend systems for advertising and e-commerce platforms, focusing on scalable microservices and real-time data processing using Kotlin and Spring Boot. You will design low-latency services, contribute to system architecture, and support production environments in a high-scale setting. The position also emphasizes AI-assisted development practices and collaboration within engineering teams. 🗂️ Requirements: 3+ years of backend development experience, Very good knowledge of Kotlin, Very good knowledge of Spring Boot, Hands-on experience with microservices architecture, Experience with NoSQL databases, Experience with MongoDB, Experience building and maintaining backend systems and APIs, Understanding of system design and scalable architecture, Experience with high-performance and high-scale systems, English B2 level, Polish C1 level, Work permit in the European Union, Openness to occasional visits to Warsaw office, Experience using AI-powered coding assistants 📃 Skills: Kotlin, SpringBoot, MongoDB, NoSQL, Microservices, REST, APIs, GenAI, Claude, GitHubCopilot, Cursor, AWS, Azure 🏢 Description: 🟣 You will be: developing and maintaining backend systems for advertising and e-commerce platforms, building low-latency, high-performance services processing large volumes of data, developing scalable microservices and APIs using Kotlin and Spring Boot, working on real-time event processing and advertising targeting mechanisms, contributing to architecture design and system scalability improvements, collaborating with stakeholders and supporting engineering best practices, including code reviews and code quality standards, participating in technical readiness/on-call support for production incidents a few days per month. 🟣 Your profile: 3+ years of professional experience in backend development, very good knowledge of Kotlin and Spring Boot, openness to occasional visits to the Warsaw office (1–2 days per quarter), hands-on experience with microservices architecture, practical experience working with NoSQL databases, especially MongoDB, experience building and maintaining backend systems and APIs, understanding of system design and scalable architecture principles, experience working with high-performance and high-scale systems, strong analytical thinking and problem-solving skills, ability to collaborate effectively with stakeholders and engineering teams, good communication skills in English (B2) and Polish (C1), practical experience using AI-powered assistants (e.g. Claude Code, GitHub Copilot, Cursor) to improve productivity, quality, or decision-making in software delivery. Work from the European Union region and a work permit are required. 🟣 Nice to have: experience applying GenAI in a more structured way within the SDLC, including defined workflows, prompt patterns, or tool integrations embedded into daily work, interest in and familiarity with emerging AI-driven practices (e.g. agent-based workflows, automation patterns, AI-augmented development), with a willingness to explore and experiment beyond standard approaches. 🟣 Recruitment Process: CV review – HR call – Technical Interview – Client Interview – Decision 🎁 Benefits 🎁 ✍ Development: development budgets of up to 6,800 PLN, we fund certifications e.g.: AWS, Azure, access to Udemy, O'Reilly (formerly Safari Books Online) and more, events and technology conferences, technology Guilds, internal training, Xebia Upskill. 🩺 We take care of your health: private medical healthcare, multiSport card - we subsidise a MultiSport card, mental Health Support. 🤸‍♂️ We are flexible: B2B or employment contract, contract for an indefinite period.

🏢 Summary: Offer for a .NET Backend Developer focused on building backend services in a microservices and cloud-native environment. The role includes developing REST APIs, API-to-API integrations, data access layers, and collaborating in Scrum teams using modern backend technologies. 🗂️ Requirements: Experience as .NET Backend Developer, Practical knowledge of .NET, Knowledge of Scrum, Practical knowledge of Git, Experience with API-to-API communication, Knowledge of asynchronous programming, Experience designing and implementing REST API, Practical knowledge of Entity Framework, Good knowledge of SQL, Experience with PostgreSQL, Experience with microservices architecture, Knowledge of Cloud Native solutions 📃 Skills: .NET, Scrum, Git, REST, EntityFramework, SQL, PostgreSQL, Microservices, CloudNative, Async, API, AWS, Kubernetes, KQL, SIEM, Elastic, Hangfire, gRPC, GraphQL 🏢 Description: O projekcie Poszukujemy .NET Backend Developera do realizacji projektów opartych o architekturę mikroserwisową i rozwiązania cloud-native. Rola obejmuje rozwój usług backendowych, integrację systemów poprzez API oraz współpracę z zespołem projektowym zgodnie z metodyką Scrum. Twój zakres obowiązków projektowanie i rozwój aplikacji backendowych w technologii .NET implementacja oraz rozwój mikroserwisów tworzenie i rozwój REST API integracja systemów z wykorzystaniem komunikacji API-to-API projektowanie i rozwój rozwiązań opartych o architekturę cloud-native współpraca z zespołem projektowym w metodyce Scrum rozwój oraz utrzymanie warstwy dostępu do danych udział w przeglądach kodu oraz stosowanie dobrych praktyk programistycznych Nasze wymagania doświadczenie jako .NET Backend Developer praktyczna znajomość .NET znajomość metodyki Scrum praktyczna znajomość Git doświadczenie w komunikacji API-to-API znajomość programowania asynchronicznego (Async) doświadczenie w projektowaniu i implementacji REST API praktyczna znajomość Entity Framework dobra znajomość SQL doświadczenie z PostgreSQL doświadczenie w pracy z architekturą mikroserwisową znajomość rozwiązań Cloud Native Mile widziane znajomość AWS doświadczenie z Kubernetes znajomość KQL doświadczenie z SIEM znajomość Elastic znajomość Hangfire doświadczenie z gRPC znajomość GraphQL

🏢 Summary: Oferta dotyczy rozwoju i utrzymania backendu dla platformy wsparcia edukacyjnego online, z naciskiem na projektowanie architektury, rozwój API oraz optymalizację aplikacji produkcyjnych. Rola obejmuje pracę z Pythonem i FastAPI przy rozwijaniu skalowalnych systemów backendowych oraz udział w decyzjach technologicznych. Kandydat będzie odpowiadać za stabilność, bezpieczeństwo i jakość platformy. 🗂️ Requirements: Minimum 3 lata komercyjnego doświadczenia w tworzeniu systemów backendowych, Znajomość Python, Znajomość FastAPI, Znajomość PostgreSQL, Znajomość Redis, Znajomość SQL, Znajomość Docker, Znajomość Git, Doświadczenie w projektowaniu architektury systemów backendowych, Doświadczenie w projektowaniu API i logiki biznesowej, Praktyczne doświadczenie z asynchronicznym Pythonem, Doświadczenie z pytest i testami automatycznymi, Bardzo dobra znajomość relacyjnych baz danych i optymalizacji SQL, Doświadczenie z monitoringiem, logami i diagnozowaniem problemów produkcyjnych, Znajomość Jira i Confluence, Doświadczenie z CI/CD i automatyzacją wdrożeń 📃 Skills: Python, FastAPI, PostgreSQL, Redis, SQL, Docker, Git, pytest, Jira, Confluence, CI/CD, React 🏢 Description: Szukamy Mid Backend Developera, który/a wesprze zespół w budowaniu wysokiej jakości rozwiązań. Projekt nad którym obecnie pracujemy to Zajęcia w Chmurze, czyli miejsce gdzie uczniowie Szkoły w Chmurze, posiadający opinię lub orzeczenie, mogą korzystać z bezpłatnego wsparcia specjalistycznego online. Poszukujemy osoby z minimum 3-letnim doświadczeniem komercyjnym w tworzeniu systemów backendowych. Wymagania Python; FastAPI; PostgreSQL; Redis; SQL; Docker; Git. Doświadczenie i kompetencje: doświadczenie w projektowaniu architektury systemów backendowych; bardzo dobra umiejętność debugowania, diagnozowania i optymalizacji aplikacji produkcyjnych; doświadczenie w projektowaniu API oraz modelowaniu złożonej logiki biznesowej; bardzo dobra znajomość relacyjnych baz danych oraz optymalizacji zapytań SQL; praktyczne doświadczenie z asynchronicznym Pythonem; doświadczenie w tworzeniu i utrzymywaniu testów automatycznych z wykorzystaniem pytest; wysoka dbałość o jakość, czytelność, utrzymywalność i skalowalność kodu; samodzielność w analizie problemów i proponowaniu rozwiązań technicznych; doświadczenie w pracy z monitoringiem, logami oraz diagnozowaniem problemów na środowiskach produkcyjnych; znajomość narzędzi Atlassian (Jira, Confluence); doświadczenie z procesami CI/CD oraz automatyzacją wdrożeń. Zakres odpowiedzialności: rozwój aplikacji backendowych oraz nadzór nad jakością implementacji; projektowanie i rozwój API oraz logiki biznesowej; identyfikowanie obszarów wymagających refaktoryzacji i usprawnień architektonicznych; optymalizacja wydajności aplikacji, baz danych oraz procesów backendowych; diagnozowanie i rozwiązywanie złożonych problemów produkcyjnych; dbanie o stabilność, bezpieczeństwo i utrzymywalność platformy. Mile widziane: podstawowa znajomość zagadnień frontendowych, w tym React; doświadczenie z integracjami zewnętrznymi (API dostawców, IdP/OIDC, usługi mailowe itp.); znajomość zagadnień związanych z bezpieczeństwem aplikacji webowych, w tym uwierzytelniania, autoryzacji, kontroli dostępu oraz ochrony danych. Jak wygląda praca u nas: masz realny wpływ na architekturę systemu, kierunek rozwoju technologicznego oraz standardy pracy zespołu; uczestniczysz w kluczowych decyzjach dotyczących produktu i technologii; rozwijasz produkt, który jest aktywnie wykorzystywany i stale rozwijany; masz przestrzeń do proponowania własnych rozwiązań, usprawnień i inicjatyw technicznych; stawiamy na pragmatyczne, proste i skuteczne rozwiązania zamiast niepotrzebnej złożoności; pracujesz w zespole opartym na bezpośredniej komunikacji i szybkim podejmowaniu decyzji; masz wpływ zarówno na implementację, jak i na procesy techniczne oraz organizację pracy zespołu; cenimy odpowiedzialność, partnerstwo i proaktywną postawę; działamy bez rozbudowanych struktur korporacyjnych - decyzje podejmujemy szybko i blisko zespołu. Co oferujemy: pracę wśród życzliwych i wspierających osób – stawiamy na relacje i dobrą atmosferę, mówimy sobie po imieniu. wpływ i nieskrępowany rozwój – Twoje pomysły i rozwiązania traktujemy na serio, pracę z biura (Warszawa-Żoliborz) dofinansowanie do karty MultiSport i opieki medycznej – lubimy sport, dbamy o zdrowie. 🔎 Proces rekrutacji: 1. Przegląd zgłoszeń 2. 10-minutowy video screening z wybranymi kandydatami 3. 40-minutowy test kompetencji logicznych 4. Zadanie rekrutacyjne i rozmowa z zespołem

🏢 Summary: The offer is for a Backend Developer role focused on building and maintaining high-performance, low-latency systems for advertising and e-commerce platforms. The position involves developing scalable microservices and APIs using Kotlin and Spring Boot, working with real-time event processing, and contributing to system architecture and scalability. The role also includes production support and collaboration within cross-functional engineering teams. 🗂️ Requirements: 3+ years of professional experience in Java backend development, Very good knowledge of Kotlin, Very good knowledge of Spring Boot, Hands-on experience with microservices architecture, Practical experience with NoSQL databases, Experience with MongoDB, Experience building and maintaining backend systems and APIs, Understanding of system design and scalable architecture principles, Experience with high-performance and high-scale systems, English level B2, Polish level C1, Experience with AI-powered coding assistants, Work permit for EU and ability to work from EU region, Availability for occasional visits to Warsaw office 📃 Skills: Java, Kotlin, Spring, SpringBoot, Microservices, MongoDB, NoSQL, REST, API, AI, Claude, Copilot, Cursor 🏢 Description: 🟣 You will be: developing and maintaining backend systems for advertising and e-commerce platforms, building low-latency, high-performance services processing large volumes of data, developing scalable microservices and APIs using Kotlin and Spring Boot, working on real-time event processing and advertising targeting mechanisms, contributing to architecture design and system scalability improvements, collaborating with stakeholders and supporting engineering best practices, including code reviews and code quality standards, participating in technical readiness/on-call support for production incidents a few days per month. 🟣 Your profile: 3+ years of professional experience in Java backend development, very good knowledge of Kotlin and Spring Boot, openness to occasional visits to the Warsaw office (1–2 days per quarter), hands-on experience with microservices architecture, practical experience working with NoSQL databases, especially MongoDB, experience building and maintaining backend systems and APIs, understanding of system design and scalable architecture principles, experience working with high-performance and high-scale systems, strong analytical thinking and problem-solving skills, ability to collaborate effectively with stakeholders and engineering teams, good communication skills in English (B2) and Polish (C1), practical experience using AI-powered assistants (e.g. Claude Code, GitHub Copilot, Cursor) to improve productivity, quality, or decision-making in software delivery. immediate availability or a short notice period is preferred. Work from the European Union region and a work permit are required. 🟣 Nice to have: experience applying GenAI in a more structured way within the SDLC, including defined workflows, prompt patterns, or tool integrations embedded into daily work, interest in and familiarity with emerging AI-driven practices (e.g. agent-based workflows, automation patterns, AI-augmented development), with a willingness to explore and experiment beyond standard approaches. 🟣 Recruitment Process: CV review – HR call – Technical Interview – Client Interview – Decision 🎁 Benefits 🎁 ✍ Development: development budgets of up to 6,800 PLN, we fund certifications e.g.: AWS, Azure, access to Udemy, O'Reilly (formerly Safari Books Online) and more, events and technology conferences, technology Guilds, internal training, Xebia Upskill. 🩺 We take care of your health: private medical healthcare, multiSport card - we subsidise a MultiSport card, mental Health Support. 🤸‍♂️ We are flexible: B2B or employment contract, contract for an indefinite period.

🏢 Summary: Backend Developer role focused on building and evolving a scalable music streaming backend platform. The position involves designing, implementing, and maintaining high-performance backend services that support content discovery and playback in a distributed, high-load environment. You will work in an agile team to deliver reliable, testable, and maintainable solutions. 🗂️ Requirements: Strong experience with .NET and C#, Knowledge of Object-Oriented Design (OOD), Understanding of SOA and SOLID principles, Experience with SQL databases, Experience with NoSQL databases, Ability to design and consume RESTful APIs, Experience with distributed and high-load systems, Familiarity with CI/CD pipelines, Proficiency with Git version control 📃 Skills: .NET, C#, OOD, SOA, SOLID, SQL, NoSQL, REST, CI/CD, Git, Distributed, High-load 🏢 Description: We are looking for a Backend Developer to join the product development of Music Backend (BE) platform . You will be part of a team responsible for building and evolving a scalable streaming platform, delivering product and business improvements in close collaboration with cross-functional teams. Your responsibilities: Contribute to the development and improvement of the backend music streaming platform Design and implement scalable, testable, and maintainable backend solutions using appropriate architectural patterns Collaborate with Product Owners and cross-functional teams to shape user experience Develop and maintain front-facing backend services enabling content discovery and playback Ensure operational stability through monitoring, upgrading, and maintaining backend systems Write high-quality code with a strong focus on performance, reliability, and customer value Explore and apply modern technologies within the backend ecosystem Work in an agile development environment We are looking for you, if you have: Strong experience with .NET / C# Solid understanding of Object-Oriented Design (OOD) , SOA , and SOLID principles Experience with SQL and NoSQL databases Experience designing and consuming RESTful APIs Experience with distributed, large-scale, high-load systems Familiarity with CI/CD pipelines Experience using Git for version control Nice to have Experience with application monitoring (preferably Datadog ) Experience working with MongoDB Knowledge of AWS Experience developing in Python Experience with GraphQL We offer: Participation in interesting and demanding projects Flexible working hours A great, non-corporate atmosphere Stable employment conditions (contract of employment or B2B contract) Opportunities for development and promotion Attractive package of benefits Work model: remote or hybrid (2 days per week from the office) We reserve the right to contact the selected candidates.

🏢 Summary: Backend Tech Lead role focused on leading and implementing a strategic rewrite of a core financial platform module into a modern, scalable architecture. The position combines hands-on Java/Spring Boot development with architectural decision-making, API design, and integration across multiple enterprise banking systems. It involves designing high-performance backend services handling large transactional and reporting datasets. 🗂️ Requirements: 7+ years backend or fullstack development experience, Strong Java expertise, Strong Spring Boot expertise, Experience designing REST APIs, Experience as Tech Lead or technical owner, Experience designing scalable and distributed systems, Strong relational database design skills (PostgreSQL), Experience with Elasticsearch or similar search technology, Experience integrating external systems via REST or GraphQL, Experience with Docker and Kubernetes, Experience with CI/CD pipelines, Knowledge of OAuth2 and OIDC, Working knowledge of React, Working knowledge of TypeScript, Experience handling large datasets with complex queries, Ability to lead architecture and mentor developers 📃 Skills: Java, Spring, SpringBoot, REST, GraphQL, PostgreSQL, Elasticsearch, Docker, Kubernetes, CI/CD, OAuth2, OIDC, React, TypeScript, SQL, Microservices, DistributedSystems 🏢 Description: Our client is an international financial technology company building solutions that support transaction communication, balances visibility, reporting, and integrations across multiple banking systems . We are looking for a Backend Tech Lead to join a strategic rewrite of a core platform module. The role combines technical leadership with hands-on backend development , helping redesign a legacy component into a modern, scalable architecture. You will work closely with product stakeholders, platform engineers, and frontend teams to design and implement reliable, high-performance backend services that integrate multiple enterprise systems. IN SHORT: 🌍 Remote work or on-site (Wrocław, Bielsko-Biała) – your choice! 💰 170 - 190 PLN/h + VAT ☑️ B2B contract Your Daily Missions Lead the design and development of backend services for a core platform rewrite. Design scalable services responsible for transactions, balances, statements, and reporting data . Define API contracts and integration patterns between backend services, frontend applications, and external enterprise systems. Make key decisions around data modeling, search/indexing strategies, and performance optimization for million-row datasets with complex filtering, sorting, and pagination . Support frontend teams by ensuring API-first design and smooth integration with React applications . Ensure engineering quality through code reviews, architecture discussions, and mentoring other developers . Collaborate closely with product, frontend, and platform teams to deliver robust, production-ready systems . The Essentials We're Seeking 7+ years of experience in backend or fullstack software development. Strong expertise in Java and Spring Boot , including designing modular backend services and REST APIs. Experience acting as a Tech Lead or technical owner responsible for architectural decisions. Solid experience designing scalable APIs and distributed systems . Strong understanding of data modeling in relational databases (e.g., PostgreSQL) and designing efficient query patterns. Practical experience with Elasticsearch (or similar search/indexing technologies) for filtering, search, and aggregation over large datasets. Experience designing hybrid data architectures combining multiple data sources . Experience working with external system integrations , including REST or GraphQL APIs. Familiarity with containerized environments (Docker, Kubernetes) and modern CI/CD pipelines. Understanding of security patterns in enterprise systems (OAuth2, OIDC, authentication and authorization flows). Working knowledge of React and TypeScript , enabling effective collaboration with frontend teams. Proven ability to break down complex architectural changes into manageable development phases . Experience using AI-assisted development tools (e.g., Cursor, Claude Code, or similar agentic coding tools) and openness to experimenting with AI-driven approaches to improve development efficiency and engineering workflows . Ability to combine hands-on engineering with technical leadership and mentoring . Nice-to-Haves Experience in FinTech, banking, or enterprise integration platforms . Experience with large-scale transactional or reporting systems . Experience with GraphQL integrations . Experience with data migration or legacy system modernization . Experience designing API-first platforms . Familiarity with observability practices (logging, metrics, tracing). Understanding of database partitioning and query optimization patterns . Reasons Why You Would Enjoy Working With Us We work in the latest technologies and with international clients, and our projects are polished from < to /> - learn about some of the projects we have completed. We organize TechTalks, meet-ups and create guilds where we exchange knowledge - you can learn a lot from your teammates. We have a close-knit team and we make sure to have regular integrations - we often go out to celebrate together. You can work remotely or choose to work from our offices in Wroclaw or Bielsko-Biala. However, we count on your openness to occasionally visit the office for team meetings or client visits, or possible occasional trips to the client's headquarters. You can adjust your working hours to suit your needs, starting your day between 7:00 and 10:00 am. You can work with great specialists in their fields who also have a sense of humor and other after-hours hobbies. It is the people who create the unique atmosphere and relaxed atmosphere at CSHARK. We have a flat structure - we are not a corporation and don't want to be one 🙃. We offer bonuses for employee referrals (from 3000 PLN to 7000 PLN). We organize remote English classes and provide access to the company library. You can also become an author/author of articles published on our technical blog - https://cshark.com/blog/ .

🏢 Summary: Backend .NET Developer role focused on building and enhancing a production-ready, cloud-based platform with strong emphasis on AI-driven solutions. The position involves designing scalable backend services within a cross-functional team and contributing to technical and product decisions. Developers work with modern technologies to deliver high-impact features in a stable architecture. 🗂️ Requirements: 3+ years experience in backend web application development, .NET 8 and C# proficiency, Experience with Docker, Experience with PostgreSQL, DynamoDB or Elasticsearch, Experience with Entity Framework, Familiarity with AI and Large Language Models (LLMs), Ability to read and understand Python code, Experience designing scalable cloud-based solutions, English proficiency for technical communication 📃 Skills: C#, .NET, PostgreSQL, DynamoDB, Elasticsearch, EntityFramework, Docker, AWS, Python, AI, LLM 🏢 Description: At Big Blue Marble, we work on our own production-ready platform, already used by clients around the world. The product is stable and well-designed, which allows our developers to focus on building new, high-impact features rather than dealing with legacy code or unstable architecture. It’s a rewarding environment where your work directly contributes to real outcomes and you have room to explore and improve existing solutions. As a Backend .NET Developer , you will join a cross-functional team building cloud-based solutions, with a strong focus on AI-driven products. You will take part in both technical and product discussions, helping design robust and scalable solutions. We value ownership, transparency, and collaboration, and we provide the tools and support you need to do your best work. Our tech stack: C# with the .NET 8, Databases: PostgreSQL, DynamoDB and Elasticsearch, ORM: entity framework, Docker, AWS. What we expect: At least 3+ years of experience in developing web applications (as a backend developer), Familiarity with AI, especially Large Language Models (LLMs), Experience working with Docker, Ability to read and understand Python code, very good knowledge of C# and .NET 8, Analytical thinking skills and being able to translate organizational/business requirements into service functionalities, being able to solve problems and make decisions independently, communicative English, good teamwork and learning skills. Even better if you also have: knowledge of the AWS cloud. familiarity with video processing and distribution. What you’ll get in return: compensation in the range of 12 500 - 17 000 PLN net B2B, fully remote work with flexible working hours, one full day per sprint for learning and development, access to the MyBenefit platform, including the option to join the MultiSport program and use other services, a choice to join our group health insurance, access the wellbeing platform Mindgram that helps you stay in a good mental shape, access to the language learning platform Tutlo, company-wide quarterly meetings (when we head out together, sum up the quarter, have fun, and enjoy spending time as a team), optional (bun fun!) team activities, like joint mountain trekking trips, St. Nicolas Day event for kids, board game nights, and more, a welcoming office in the very heart of Poznań, if you prefer to work on-site. If you’d like to join our team, leave your CV below. We’d be happy to get in touch with you! Recruitment process: Interview with People Operations Specialist - a 30-minute online meeting to get to know each other better, Interview with the Chapter leader and the People Operations Specialist - a more in-depth conversation about the role and mutual expectations, lasting about 1 hour. You can count on our feedback after each stage to ensure the process is as transparent and valuable as possible.

🏢 Summary: Backend Engineer role focused on designing, building, and maintaining scalable backend services in a cloud-native AWS environment. The position involves developing production-grade APIs and services using TypeScript and .NET, with strong emphasis on CI/CD, Infrastructure as Code, and cloud-native best practices. The role supports secure, scalable backend systems with close collaboration across platform and operations teams. 🗂️ Requirements: Strong experience building and maintaining scalable APIs and backend services, Hands-on experience with CI/CD pipelines using GitHub Actions or GitHub Workflows, Strong development experience with TypeScript, Strong development experience with .NET (C#), Experience deploying and operating workloads in AWS Cloud, Experience using Terraform for Infrastructure as Code, Experience designing and consuming RESTful APIs or event-driven services, Understanding of cloud-native patterns, Experience with relational databases and SQL, Fluent English 📃 Skills: TypeScript, .NET, C#, AWS, Terraform, SQL, REST, CI/CD, GitHub, GitHubActions, APIs, IAM, Lambda, ECS, Fargate 🏢 Description: We are looking for a Backend Engineer to design, build, and maintain backend services in a modern cloud-native AWS environment. Core skills & experience: Strong experience as a Backend Developer, building and maintaining scalable APIs and backend services Hands-on experience with CI/CD pipelines, preferably using GitHub Actions / GitHub Workflows Strong development experience with TypeScript and .NET (C#), including building and operating production services Familiarity with AWS Cloud, including deploying and operating backend workloads in AWS Experience using Terraform for Infrastructure as Code (IaC) Related technologies / domain knowledge: Experience designing and consuming RESTful APIs and/or event-driven backend services Understanding of cloud-native patterns (stateless services, scaling, resiliency, observability) Experience working with relational databases (SQL) and backend integrations Nice-to-have / preferred experience: Experience with containerized workloads (e.g. ECS Fargate or similar) Experience with Lambda functions Familiarity with IAM and AWS security best practices Exposure to data platforms or ETL-heavy environments Experience working in environments with high operational and security requirements General expectations: Able to take ownership of backend services from development through production Comfortable working closely with platform, data, and operations engineers Focused on clean code, automation, and reliable delivery through CI/CD Used to working with SCRUM principles, preferably in JIRA Fluent English Other Details: The role is designed for a cloud-native environment, supporting development across various backend services focused on scalability and security.