 
						Senior Software Engineer
2 weeks ago
5+ years of experience with building SaaS applications using JavaScript/TypeScript (including Node.js) Experience with database system design, RDBMs, or NoSQL Openness to work with other languages like Python Experience with developing back-end - nice to have Experience with Amazon Web Services or Google Cloud Platform Communicative Polish and English At OpenX, we have built a team that is uniquely experienced in designing and operating high-scale ad marketplaces, and we are constantly on the lookout for thoughtful, creative executors who are as fascinated as we are about finding new ways to apply a blend of market design, technical innovation, operational excellence, and empathetic partner service to the frontiers of digital advertising. Our exchange handles billions of ad requests daily, connecting thousands of publishers with demand partners. It’s fully containerized, running in the cloud in multiple regions across the world. Ads from our systems can be seen in your favored mobile game, web page, or maybe TV in the future. That’s the place where each millisecond matters. The team is using the following technologies: Frontend: JS/TS, React, Material UIAPI: PythonCICD: Cloudbuild, Spinnaker We are operating at a scale: 100% Cloud-based (GCP) platform Over 370 billion Ad requests every day Over 120 000 CPU daily Over 140 TB RAM daily Over 50 PB of data per week Over 1200 production deployments a month ,[Design high-performance, distributed, low-latency systems, Architect, create, and deliver new features and functionality, Work with Product to drive the requirements, and own the project end-to-end, Work with Product and UX teams to bring consumer-grade user experience and design to the enterprise, Work with Engineering and Product teams distributed across multiple locations, Analyze and improve efficiency, scalability, and stability of servers and processes, Think long-term and be unsatisfied with band-aids, Identify unnecessary complexity and remove it] Requirements: JavaScript, TypeScript, Node.js, RDBMS, React, GCP/AWS, Python Tools: Jira, Confluence, GitHub, GIT, Cloud Build, Agile, Scrum. Additionally: Small teams, International projects, Private healthcare, Lunch card, Multikafeteria, Life & group insurance, Flat structure, Free coffee, Canteen, Bike parking, Shower, Free snacks, Free beverages, Free lunch, Free parking, In-house trainings, Modern office, No dress code.
- 
					  Senior .Net Software Engineer @ uSoftware2 weeks ago 
 Remote, Czech Republic uSoftware Full timeQualifications C#, ASP.NET MVC and WebAPI Solid experience with SQL Server, including hand-written queries, relational database design Knowledge of RESTful services Experience with data pipeline engineering, database design, web platform development, API design, or distributed systems Web development using HTML5, CSS, JavaScript, and JQuery, with at... 
- 
					  Senior .Net Software Engineer @ uSoftware2 days ago 
 Remote, Czech Republic uSoftware Full timeQualifications 8+ years of experience with C#, ASP.NET MVC and WebAPI Solid experience with SQL Server, including hand-written queries, relational database design Knowledge of RESTful services Experience with data pipeline engineering, database design, web platform development, API design, or distributed systems Web development using HTML5, CSS,... 
- 
					  Senior Software Engineer Kotlin @ Antal2 weeks ago 
 Remote, Warszawa, Czech Republic Antal Full timeAt least a decade of professional experience in back-end development including 3+ years with Kotlin and in a technical leadership role as well Strong proficiency in Kotlin and solid understanding of modern backend architecture (e.g., microservices, REST, event-driven design) Experience with Spring framework (with Kotlin) Deep knowledge of modern... 
- 
					  Senior Software Engineer @ OpenVPN2 weeks ago 
 Remote, Czech Republic OpenVPN Full time5+ years of software engineering experience, designing and deploying distributed systems at scale. 3+ years of hands-on experience with Go (Golang), including concurrency, memory management, networking, and performance tuning. Deep understanding of network-level protocols and enforcement (TCP/IP, UDP, DNS, TLS, iptables/nftables, conntrack). Proven... 
- 
					  Senior Software Engineer2 days ago 
 Remote, Czech Republic Superdevs Full timeWhat you bring Strong background as a Software Engineer with Java, Linux, Docker, GitLab, SQL Experience running Elastic Stack on AWS (5+ years in enterprise environments) 3+ years working with ML / Deep Learning / Data Science / Search or Analytics topics Hands-on experience designing or optimizing search systems at scale Experience with GitLab CI/CD for... 
- 
					  Senior Software Engineer2 weeks ago 
 Remote, Kraków, Czech Republic Appliscale Full time5+ years of experience in C++ 17 3+ years of experience in Java/Scala Experience in building data pipelines or data products Experience with streaming technologies, e.g. Kafka Connect Experience with data serialization (Protobuf, Thrift or Parquet) Bachelor's or higher degree in Computer Science, Software Engineering, or a related field Effective... 
- 
					  Senior Software Java Engineer @ Antal7 days ago 
 Kraków, Czech Republic Antal Full timeExperience in developing and supporting mission-critical applications. Prior experience with financial systems such as Valuation Engines, Trade Store or product-based applications. Strong hands-on skills in Core Java and Spring Boot. Solid knowledge of microservices architecture and design patterns. Preferred: experience with Google Cloud Platform (GCP),... 
- 
					  Senior Software Engineer7 days ago 
 Remote, Czech Republic Merit Full timeYour Profile Strong technical foundation; comfortable coding in at least two modern languages. Track record of delivering production systems independently. Experience across varied environments (consulting, freelance, agency, or startup). Curious and active in AI-assisted development (e.g., Copilot, Claude, Cursor, self-hosted LLMs). Experience building or... 
- 
					  Senior Software Engineer7 days ago 
 Remote, Kraków, Czech Republic OpenX Full timeRequired Qualifications: Ideally, 5+ years of working experience in Java Experience with database system design, RDBMS, or NoSQL Experience with Google Cloud Platform, k8s, and Docker Communicative Polish and English Ability to effectively dive into technologies other than Java (Erlang, GO) Desired Characteristics: Fluently speak algorithms and data... 
- 
					  Senior Embedded Software Engineer @ SquareOne2 weeks ago 
 Remote, Warsaw, Czech Republic SquareOne Full timeRequired Skills & Experience Minimum 5 years of professional experience in real-time embedded systems and software engineering. Strong proficiency in C++ for embedded system development. Deep understanding of machine learning models and inference execution on specialized hardware accelerators. Expertise in scheduling and load-balancing...