Senior RoR Developer

🏢 Summary: Senior individual contributor role focused on building and delivering scalable software systems while shaping technical direction and standards. The position combines hands-on Ruby/Rails development with system design, cross-team technical leadership, and mentoring. The engineer will lead complex initiatives and drive architectural decisions in a modern distributed stack. 🗂️ Requirements: Strong experience with Ruby, Experience with Rails framework, Experience designing scalable systems, Proven experience leading complex cross-team technical projects, Ability to make architectural decisions, Experience mentoring engineers, Experience with distributed systems and backend integrations, Ability to work with PostgreSQL and Redis, Experience working with React frontend, Experience with Kafka, Elasticsearch, and Kubernetes 📃 Skills: Ruby, Rails, PostgreSQL, Redis, React, Kafka, Elasticsearch, Kubernetes, HR, Fintech, Accounting 🏢 Description: We are looking for a Senior Engineer to join our team and help us build and deliver software at scale. We have a flat structure, but this is a very senior individual role for someone who can make a big impact. In this role, you will take initiative, solve complex problems, improve our technical standards, and support other engineers. You will work closely with leadership to shape our technical direction while still writing code. Our Tech Stack Ruby 3.3.8 & Rails 7.2 PostgreSQL & Redis React (frontend) Kafka, Elasticsearch, Kubernetes (K8s) What you will do Drive technical work: Help turn high-level goals into clear projects and plans. Support the team: Mentor both junior and senior engineers to help them grow. Set standards: Improve how we work and make sure our code stays maintainable in the future. Handle uncertainty: Work without clear instructions at times, set direction, and guide others. Solve complex problems: Take the lead on difficult issues and important technical decisions. What we are looking for Strong experience with Ruby Experience in HR, Fintech, or Accounting systems is a plus Proven impact: experience leading complex projects across teams Good communication: able to work with both engineers and non-technical stakeholders Initiative: able to find important problems and follow through with solutions The process Screening call: 15-minute chat with a recruiter System design interview: 60-minute discussion about architecture Behavioral interview: 60-minute conversation about your experience and teamwork Final call: conversation with the CEO

🏢 Summary: Senior Software Engineer role focused on developing and scaling a robust platform using Ruby on Rails, with responsibility for building secure services and APIs. The position involves implementing new features, improving system performance, and supporting integrations with external partners. This hybrid role in Warsaw includes technical ownership of developed services and participation in agile processes. 🗂️ Requirements: Minimum 5 years of professional Software Engineering experience, Strong proficiency in Ruby on Rails, Experience with React and component-based frameworks, Working knowledge of JavaScript or TypeScript, Experience developing and managing APIs, Ability to work in a hybrid (office/remote) model, Advanced written and spoken English 📃 Skills: Ruby, Rails, React, JavaScript, TypeScript, GraphQL, APIs, Agile 🏢 Description: Our Client, an American software company is opening a new branch in Warsaw and we are looking for a Senior Software Engineer with Ruby to join a growing team. About the Position This role focuses on enhancing and maintaining a robust platform, supporting new project initiatives, and delivering scalable solutions that improve the user experience for both industry professionals and individual clients. The ideal candidate is proactive, collaborative, and committed to delivering high-quality, scalable software. This is a hybrid role based in Warsaw, Poland. Key Responsibilities Design and implement new functionalities for a cutting-edge platform Develop and manage APIs to enable smooth integration with financial and sales partners Build secure and scalable services designed for sustained performance Support agile development practices and help ensure consistent, impactful sprint results Mentor team members and contribute to a positive engineering culture through knowledge-sharing Maintain and take responsibility for services you develop, including participating in the on-call rotation Requirements Minimum 5 years of professional experience as a Software Engineer Strong proficiency with Ruby on Rails Excellent communication skills and experience working in cross-functional teams Familiarity with React and component-based front-end frameworks Working knowledge of JavaScript and/or TypeScript Ability to perform in a hybrid (office/remote) work environment Advanced written and spoken English (please provide your CV in English) Nice to have Experience with GraphQL

🏢 Summary: Senior Software Engineer role focused on building and maintaining scalable Ruby on Rails solutions for a clean-energy platform used by solar professionals. The position involves developing backend services and APIs, collaborating across teams, mentoring engineers, and contributing to high-quality product delivery in a hybrid work environment. 🗂️ Requirements: 5+ years of professional software engineering experience, Strong proficiency in Ruby on Rails, Experience with React, Knowledge of JavaScript, Knowledge of TypeScript, Clear communication skills, Ability to work in a distributed remote environment, Strong English communication skills 📃 Skills: Ruby, Rails, React, JavaScript, TypeScript, GraphQL, APIs 🏢 Description: Senior Software Engineer (Ruby on Rails) 💰 Salary: 19,000-28,000 PLN 🌎 Hybrid (2 days on site) ☑️ Full-time 🕦 Contract through Deel We’re looking for a Senior Software Engineer for a leading software provider in the clean-energy space, building technology that helps solar professionals design and sell solar projects accurately and at scale. Their platform has powered millions of solar designs and is recognized as one of the top remote-friendly and sustainability-focused companies in the industry. Requirements: 5+ years of professional software engineering experience. Strong proficiency with Ruby on Rails. Clear communication skills and comfort working cross-functionally. Familiarity with React and component-based frontend development. Working knowledge of JavaScript and/or TypeScript. Ability to thrive in a fully remote, distributed environment. Strong English skills (written and spoken). Nice to Have Experience with GraphQL . Interest in renewable energy, climate tech, or mission-driven products. Responsibilities: Build new features for a leading platform used by solar professionals for design and sales. Design and maintain reliable APIs that integrate smoothly with financial and sales partners. Develop secure, scalable backend services built for long-term stability and performance. Contribute to agile planning and help drive predictable, high-quality delivery. Mentor teammates, share knowledge, and strengthen the overall engineering culture. Take ownership of the services you build, including participating in on-call rotations. Benefits Health Coverage: Medical, dental, and vision insurance Internet & Mobile Stipend Work-From-Home Support (home office budget) Learning & Development support

🏢 Summary: Full-time Senior Software Engineer role focused on building and scaling a Ruby on Rails-based platform used by solar professionals to design and sell solar projects. The position involves developing secure, high-performance backend services, reliable APIs, and contributing to frontend features in a distributed, hybrid work environment. The engineer will also support agile delivery, system ownership, and technical mentorship. 🗂️ Requirements: 5+ years of professional software engineering experience, Strong proficiency in Ruby on Rails, Experience with React and component-based frontend development, Working knowledge of JavaScript or TypeScript, Experience designing and maintaining APIs, Experience building secure, scalable backend systems, Ability to work in distributed, remote environment, Strong English communication skills 📃 Skills: Ruby, Rails, React, JavaScript, TypeScript, GraphQL, API, Backend, Agile 🏢 Description: Senior Software Engineer (Ruby on Rails) 💰 Salary: 19,000-28,000 PLN 🌎 Hybrid (2 days on site) ☑️ Full-time 🕦 Contract through Deel We’re looking for a Senior Software Engineer for a leading software provider in the clean-energy space, building technology that helps solar professionals design and sell solar projects accurately and at scale. Their platform has powered millions of solar designs and is recognized as one of the top remote-friendly and sustainability-focused companies in the industry. Requirements: 5+ years of professional software engineering experience. Strong proficiency with Ruby on Rails. Clear communication skills and comfort working cross-functionally. Familiarity with React and component-based frontend development. Working knowledge of JavaScript and/or TypeScript. Ability to thrive in a fully remote, distributed environment. Strong English skills (written and spoken). Nice to Have Experience with GraphQL . Interest in renewable energy, climate tech, or mission-driven products. Responsibilities: Build new features for a leading platform used by solar professionals for design and sales. Design and maintain reliable APIs that integrate smoothly with financial and sales partners. Develop secure, scalable backend services built for long-term stability and performance. Contribute to agile planning and help drive predictable, high-quality delivery. Mentor teammates, share knowledge, and strengthen the overall engineering culture. Take ownership of the services you build, including participating in on-call rotations. Benefits Health Coverage: Medical, dental, and vision insurance Internet & Mobile Stipend Work-From-Home Support (home office budget) Learning & Development support

🏢 Summary: Senior/Lead Ruby on Rails role focused on leading backend architecture and development while supporting frontend integration with React. The position involves driving technical direction, ensuring scalability and performance, and maintaining high code quality across the project. The role also acts as a technical point of contact aligning engineering outcomes with business goals. 🗂️ Requirements: Mastery of Ruby on Rails, Expert-level Ruby proficiency, Experience designing scalable backend architectures, Experience with React, Proven experience leading technical projects or modules, Ability to conduct code reviews and enforce best practices 📃 Skills: Ruby, Rails, React, Backend, Architecture, REST, Git, SQL 🏢 Description: We are looking for a high-level Ruby on Rails Expert to take a key role in the development team. This position is designed for someone who excels in backend architecture but can also navigate the frontend landscape when needed. As a Senior or Lead Developer, you will be responsible for the technical direction of the project, ensuring high performance, and maintaining a robust codebase while communicating effectively with international stakeholders. Responsibilities Technical Leadership: Leading the backend development lifecycle using Ruby on Rails . Architecture: Designing and implementing scalable, secure, and maintainable backend services. Full-stack Support: Collaborating on the frontend layer, specifically with React (experience here is a big plus). Code Quality: Conducting code reviews, mentoring team members, and establishing best development practices. Communication: Acting as a technical point of contact, ensuring clear alignment between technical goals and business needs. Requirements Expertise: Mastery of Ruby on Rails and the Ruby language. Frontend: Practical experience with React (highly desirable). Ownership: Proven ability to lead projects or significant technical modules. Soft Skills: Proactive attitude, strong problem-solving skills, and a "Lead" mindset.

🏢 Summary: Senior Software Engineer role focused on designing and delivering scalable solutions within complex distributed systems at significant scale. The position requires strong ownership, architectural decision-making, and collaboration across cross-functional teams. The engineer will drive high-impact technical initiatives in a large, distributed environment. 🗂️ Requirements: Degree in Computer Science or equivalent practical experience, Proven experience delivering complex, large-scale software solutions, Hands-on experience with distributed systems, Ability to make independent architectural decisions, Strong collaboration and communication skills, Ability to operate autonomously with high ownership 📃 Skills: DistributedSystems, Architecture, Scalability, Reliability, Observability, SoftwareEngineering, ComputerScience 🏢 Description: Senior Software Engineer About the Role We are looking for a Senior Software Engineer to join a high-scale product environment operating within complex distributed systems. This role is designed for a highly autonomous individual contributor who can take ownership of complex technical initiatives, influence architectural direction, and deliver scalable, reliable solutions in a large organizational setting. You will collaborate cross-functionally with engineering, product, and design teams while contributing to systems used at significant scale. Key Responsibilities Design and deliver high-complexity system components and features Make informed architectural decisions and evaluate technical trade-offs Ensure quality, scalability, reliability, and observability of delivered solutions Identify and manage technical risks, dependencies, and technical debt Develop deep understanding of the product domain and user impact Collaborate effectively across teams in a distributed engineering environment Operate with high autonomy and ownership Contribute to or elevate engineering standards within the team Mentor or support less experienced engineers when needed Requirements Education Degree in Computer Science, Software Engineering, or equivalent practical experience Experience & Competencies Proven experience as a Senior Software Engineer delivering complex, large-scale solutions Hands-on experience working with distributed systems Strong communication and collaboration skills Ability to independently drive architectural decisions Strong sense of ownership over delivered solutions Nice to Have Experience shaping or improving team-level engineering standards Experience collaborating across multiple teams in complex organizational structures

🏢 Summary: Senior Ruby on Rails Developer role focused on building and evolving a cloud-ready product into a scalable, distributed system. The position involves designing architecture, developing core services and APIs, and driving Kubernetes-based deployments with CI/CD automation. You will influence engineering standards and contribute production-ready code in a greenfield development environment. 🗂️ Requirements: 5+ years of software engineering experience, Senior-level Ruby on Rails expertise, Experience building and scaling distributed systems, Knowledge of Kubernetes, Experience with CI/CD pipelines, Experience with Infrastructure as Code, Strong API design skills, Experience with microservices communication, Ability to lead architectural initiatives, Mentoring experience for engineers 📃 Skills: Ruby, Rails, Kubernetes, CI/CD, IaC, API, Microservices, DistributedSystems 🏢 Description: We are looking for an experienced Senior Ruby on Rails Developer to join the team responsible for development of the product, which is evolving into a modern, cloud‑ready solution. In this role, you will have opportunity to influence architectural decisions, contribute production‑ready code, and collaborate closely with cross‑functional teams. Your daily responsibilities: Build and improve core platform services and APIs Design scalable, distributed system architecture Implement and optimize key components in the codebase Set engineering standards for reliability and maintainability Drive deployments using Kubernetes and CI/CD automation Collaborate across teams to align technical and product goals. Requirements: 5+ years of software engineering experience, including senior‑level work Strong proficiency in Ruby on Rails Experience building and scaling distributed systems Solid knowledge of Kubernetes, CI/CD, and IaC Strong skills in API design and microservice communication Ability to lead architectural initiatives and mentor other engineers. What we offer: Attractive salary and benefits package, including Multisport card, insurance, and medical care Hybrid work from the Krakow office International work environment in a product company Training and development opportunities within the organization Joining the greefield project with pure development. Apply now!

🏢 Summary: Remote B2B opportunity for a Senior Software Engineer focused on developing complex, high-performance systems in modern C++ within Linux environments. The role involves contributing to product-level features, collaborating across teams, and working with cloud and backend technologies. Long-term cooperation with flexibility on financial expectations and start date. 🗂️ Requirements: 6+ years of hands-on experience in C++ development, Strong knowledge of modern C++, Experience with multithreading, Understanding of memory management, Experience with performance optimization, Strong understanding of Linux-based systems, Experience developing in Linux environment, Ability to deliver complex technical features, Bachelor’s degree in Science, Technology, Engineering or related field 📃 Skills: C++, Linux, Multithreading, MemoryManagement, PerformanceOptimization, Python, Go, AWS, Terraform, CloudFormation, REST, CI/CD, GitHub, Jenkins, Artifactory, Ansible, Networking, Security, Databases 🏢 Description: For our client, we are looking for a Senior Software Engineer (f/m/n). Qualifications 6+ years of hands-on experience in C++ development (modern C++ preferred) with a solid understanding of multithreading, memory management, and performance optimization Strong experience contributing to complex features with a good product-level understanding and exposure to diverse technologies Proven ability to collaborate effectively within a team, actively participating in technical discussions and supporting delivery across multiple contributors Strong understanding of Linux-based systems and experience developing in a Linux environment (user level) Demonstrated ability to take ownership of well-defined technical tasks and drive them to completion with high quality Strong interpersonal skills with the ability to communicate clearly, collaborate effectively, and contribute confidently in professional discussions Proven ability to quickly learn and adapt to new technologies, taking on tasks with a proactive, can-do attitude and a willingness to expand beyond the core tech stack, including Python, AWS and Go Highly self-managed and independent, capable of delivering results with limited supervision while aligning with broader team goals Bachelor’s degree in Science/Technology/Engineering or a related field How will you stand out from the crowd Experience with Go and/or Python programming languages Experience with cloud-native development and infrastructure-as-code tools (e.g., Terraform, CloudFormation) Experience in enterprise-scale application development in cloud or SaaS environments (AWS serverless architecture is a definite advantage) Experience in building fullstack applications, including REST API-based backend systems and modern frontend interfaces Familiarity with networking protocols, security principles, and database systems Experience with modern CI/CD pipelines, such as GitHub, Jenkins, Artifactory, and Ansible We offer: Work model: remote Contract type: B2B with SHIMI Long-term cooperation We are open to the candidate’s financial expectations Start: ASAP (up to 1 month notice)

🏢 Summary: Senior Full Stack Engineer role focused on leading the delivery of scalable, business-critical web applications. The position combines React/Remix front-end development with Python REST APIs, Azure cloud deployment, automated testing, and DevSecOps practices while providing technical leadership in an Agile team. 🗂️ Requirements: Senior full-stack engineering experience, TypeScript, React, Python, RESTful API development, MongoDB, SQL databases, Microsoft Azure, Azure Kubernetes Service, Clean, testable code, Test-driven development, Vitest, Pytest, DevSecOps practices, GitHub workflows, GitHub Actions CI/CD, Kubernetes, ArgoCD, Problem-solving, Technical communication, Bachelor’s degree or equivalent professional experience 📃 Skills: TypeScript, React, Remix, Python, MongoDB, SQL, Azure, AKS, Vitest, Pytest, GitHub, GitHubActions, Kubernetes, ArgoCD, DevSecOps, TDD, GitOps, ES6 🏢 Description: We are seeking an experienced Senior Full Stack Engineer to join a high-performing engineering team responsible for building and enhancing innovative web-based platforms. This role offers the opportunity to work on complex, business-critical applications while driving technical excellence, engineering best practices, and scalable software solutions. As a Senior Engineer, you will take ownership of advanced development initiatives, contribute to architectural decisions, and help shape the future direction of modern web applications. You will work across both front-end and back-end technologies , combining expertise in React-based user interfaces and Python API development to deliver secure, scalable, and maintainable solutions. The ideal candidate will have strong full-stack engineering experience, a passion for clean code and automation, and the ability to solve complex technical challenges within a collaborative, agile environment. Key Responsibilities Lead the design, development, and delivery of complex software engineering initiatives from concept through to production. Architect and build scalable Python RESTful APIs and modern React/Remix-based web applications using service-oriented architecture principles. Develop reusable components, integrations, and technical solutions that improve application scalability and maintainability. Investigate, troubleshoot, and resolve complex technical issues, providing effective solutions and long-term improvements. Establish and promote engineering best practices across development, testing, security, and deployment processes. Champion a DevOps-first mindset , supporting automation, continuous delivery, and operational excellence. Define and address non-functional requirements including performance, accessibility, reliability, and security. Collaborate closely with Product Owners, architects, engineers, and business stakeholders to translate requirements into innovative technical solutions. Provide technical guidance and mentorship to other engineers, encouraging knowledge sharing and continuous improvement. Contribute to Agile delivery practices, supporting effective planning, estimation, and iterative development. Essential Skills & Experience Proven experience as a Senior Full Stack Engineer or similar technical leadership role, delivering complex software solutions. Strong proficiency in TypeScript , including modern ES6+ features and best practices. Extensive experience building dynamic, responsive front-end applications using React , with experience in Remix or similar frameworks preferred. Strong backend development experience using Python , including the design and implementation of RESTful APIs. Solid understanding of database technologies, including MongoDB and relational SQL databases. Hands-on experience with Microsoft Azure , particularly Azure Kubernetes Service (AKS) and cloud-native application deployment. Strong commitment to writing clean, maintainable, and highly testable code. Experience with Test Driven Development (TDD) and automated testing frameworks, including: Unit testing with Vitest and Pytest Functional testing exposure with Playwright is desirable. Strong understanding of modern DevSecOps practices , including: GitHub version control workflows CI/CD automation using GitHub Actions Containerised application deployment using Kubernetes GitOps practices with ArgoCD Excellent problem-solving skills with strong attention to technical detail and quality. Strong communication skills with the ability to collaborate effectively with both technical and non-technical stakeholders. Bachelor’s degree in Computer Science, Engineering, or a related discipline, or equivalent professional experience. Desirable Skills Azure Developer certification, particularly AZ-204 . Experience working with Databricks or modern data platforms. Experience working in Scrum-based Agile environments . Previous experience working with large-scale enterprise applications and distributed systems.

🏢 Summary: Senior Software Engineer role focused on designing, building, and scaling secure enterprise web applications and high-performance SaaS platforms. The position covers backend APIs, microservices, testing, technical leadership, and Azure-based CI/CD delivery within Agile teams. 🗂️ Requirements: 6+ years of full-lifecycle software development experience, Experience developing and maintaining large-scale web applications and SaaS solutions, Strong proficiency in C#, .NET Core, and .NET Framework, Hands-on experience with Azure Cloud services, RESTful architectures, and CI/CD pipelines, Experience with NUnit, Moq, Jest, and Git, Strong problem-solving and technical communication skills 📃 Skills: C#, .NET, Azure, REST, Microservices, NUnit, Moq, Jest, Git, CI/CD, SaaS 🏢 Description: We are looking for a skilled and passionate Senior Software Engineer to join our core engineering team. In this role, you will play a key part in designing, building, and scaling enterprise-grade web applications and high-performance SaaS solutions. If you have a strong foundation in Microsoft technologies, cloud architecture, and modern engineering practices—and love solving complex technical challenges—we would love to hear from you! Key Responsibilities Architecture & Development: Design, build, and maintain scalable, secure, and resilient web applications and SaaS platforms. API & Backend Systems: Implement and optimize RESTful APIs, microservices, and Web API integrations. Quality & Testing: Drive software quality by writing comprehensive unit tests (NUnit, Moq, Jest) and advocating for test-driven practices. Technical Leadership: Participate in code reviews, architectural discussions, and technical planning to ensure clean, maintainable code. Agile Collaboration: Work closely with cross-functional teams using Agile methodologies to deliver features iteratively and efficiently. DevOps & Version Control: Utilize Git and Azure DevOps for continuous integration, project tracking, and modern deployment pipelines. Key Requirements Experience: 6+ years of hands-on experience in full-lifecycle software development. SaaS & Web Architecture: Proven track record of developing and maintaining large-scale web applications and SaaS solutions. Core Tech Stack: Strong proficiency in C# , .NET Core , and .NET Framework . Cloud & DevOps: Hands-on experience with Azure Cloud services, RESTful architectures, and CI/CD pipeline concepts. Testing & Tools: Solid experience with unit testing frameworks ( NUnit, Moq, Jest ) and version control ( Git ). Communication: Excellent problem-solving skills and the ability to articulate technical concepts clearly to team members. Nice to Have Agile Frameworks: Experience working within a SAFe (Scaled Agile Framework) environment. Mentorship: Passion for coaching junior developers and fostering team growth.