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 Software Engineer responsible for defining technical standards and architecture, leading backend and frontend development, and ensuring secure, scalable, and observable solutions. The role drives CI/CD, enterprise integrations, and production support while aligning engineering practices with product and operations goals. 🗂️ Requirements: Proven experience defining technical standards and architecture, Experience with CI/CD orchestration, Experience with observability implementation, Experience implementing on-premises, hybrid, and cloud solutions, Experience leading backend and frontend architectural decisions, Experience maintaining CI/CD pipelines, Experience coordinating enterprise integrations, Knowledge of DDD and clean architecture, Expertise in Java and Spring Boot, Expertise in Python and FastAPI, Expertise in React or Angular, Experience with L2/L3 production support, Experience with Spring Security and OAuth 📃 Skills: Java, SpringBoot, Python, FastAPI, React, Angular, CICD, Observability, ServiceNow, Jira, Boomi, DDD, OAuth, SpringSecurity 🏢 Description: To strengthen the team, we are seeking a person for the role of Senior Software Engineer, responsible for defining technical standards and architecture, guiding the development team, ensuring quality practices, security, and CI/CD, and collaborating with product and operations in delivering scalable, business-aligned solutions. Main Responsibilities Define technical standards, architecture, and development practices, ensuring quality, security, performance, and resilience in production environments. Orchestrate end-to-end delivery with CI/CD and observability while promoting responsible autonomy among teams aligned with product and operational objectives. Implement on-premises, hybrid, and cloud solutions with security best practices, observability, and integration with existing systems. Lead architectural decisions in backend and frontend (Java/Spring Boot, Python/FastAPI, React/Angular), ensuring scalability, consistent testing and code reviews. Implement and maintain end-to-end CI/CD pipelines and observability (logs, metrics, distributed tracing). Coordinate enterprise integrations (ServiceNow, Jira, CRMs) and iPaaS (e.g., Boomi), including mapping, validation, and compliance. Apply practices such as DDD, clean architecture, application security, and secrets/IAM management throughout the development lifecycle. Provide technical guidance to the team, elevate quality standards, and align practices with product and operations. Lead L2/L3 support in production: incident triage and resolution, prevention escalation (on call), SLA management, and conducting post-mortems focused on root causes and corrective actions. Operate and evolve applications in on-premises, hybrid, or cloud environments: VMs, networks, VPNs, certificates, Nginx/reverse proxy, load balancing, and enhancing the security of exposed services. Key Requirements Proven ability to define technical standards, architecture, and development practices. Experience with CI/CD orchestration and observability practices. Knowledge of implementing on-premises, hybrid, and cloud solutions with security best practices. Leadership in architectural decisions for backend and frontend technologies. Experience with maintaining CI/CD pipelines and end-to-end observability. Ability to coordinate enterprise integrations and ensure compliance. Mastery of practices such as DDD and clean architecture. Technical expertise in Java/Spring Boot, Python/FastAPI, React/Angular. Experience in providing L2/L3 technical support and leading incident resolution. Expertise in security practices, including Spring Security and OAuth. Nice to Have Experience with Docker, Kubernetes, and cloud environments (Azure/AWS/GCP). Background in data management with PostgreSQL, MongoDB, and Redis. Familiarity with AI models, particularly RAG. Knowledge in security access management and policies based on the principle of least privilege.

🏢 Summary: Senior Software Engineer role focused on building and scaling a high-performance, AI-supported trade management platform using Rust and C#. The position involves designing distributed, event-driven systems with strong emphasis on performance, scalability, and reliability. The engineer will own solutions end-to-end and optimize cloud-based backend systems. 🗂️ Requirements: 5+ years of software engineering experience, Strong system design knowledge, Strong understanding of concurrency, Strong understanding of performance optimization, Hands-on Rust experience in production, Familiarity with C#/.NET, Experience with distributed systems, Experience with cloud platforms (preferably AWS), Practical use of AI tools in development workflows 📃 Skills: Rust, C#, NET, AWS, Kafka, RabbitMQ, AI, DistributedSystems, Concurrency, PerformanceOptimization 🏢 Description: Senior Software Engineer C# (AI-driven systems) We are looking for an experienced Software Engineer who combines strong system design skills with a modern, AI-supported development approach. This role focuses on building and scaling a high-performance trade management platform, primarily in Rust, with some exposure to C#/.NET. You will work on distributed, event-driven systems processing large volumes of data, with a strong focus on performance, scalability, and reliability. Key Responsibilities Develop and optimize high-performance backend systems Design and maintain scalable distributed services Use AI tools to accelerate development, testing, and debugging Own solutions end-to-end, from design to production Improve system performance and cloud efficiency Requirements 5+ years of experience in software engineering Strong fundamentals in system design, concurrency, and performance Hands-on experience with Rust (production level) Familiarity with C#/.NET Experience with distributed systems and cloud (preferably AWS) Practical use of AI tools in development workflows Nice to have Experience with messaging systems (Kafka, RabbitMQ, etc.) Exposure to financial systems or trading environments