Salary
≈ $71k – $110k per year (Estimated)
Location
In office (Warsaw)
Seniority
Senior · 10+ years exp
Employment
Full-Time
Overview
Company
Impact
Profile match
Sigma Software is a technology services company founded in 2002 as the Ukrainian development arm of the Swedish Sigma Group, and now a global organisation with delivery centres in Ukraine, Poland, Sweden, the United States and Latin America. It builds custom software for clients in advertising technology, automotive, aviation, gaming, telecommunications and the public sector, and runs its own product and startup arms alongside the services business. The company is known for keeping its Ukrainian engineering operation running through the war and for a substantial programme of technology work supporting Ukrainian defence and public institutions.
We are looking for an experienced Principal Software Engineer with deep expertise in Ruby to lead the technical direction of our platform and drive the development of complex, scalable, and high-performance systems.
In this role, you will define architectural strategy, make key engineering decisions, mentor the team, and ensure the highest standards of code quality and engineering excellence.
The ideal candidate combines strong hands-on skills with strategic thinking, product awareness, and a passion for building robust, efficient, and future-proof solutions.
- Architect and implement scalable, high-performance software solutions using Ruby and Ruby on Rails
- Lead the design and development of new features and products, ensuring code quality and best practices
- Collaborate with cross-functional teams to define and implement technical strategies
- Mentor and guide junior developers, fostering a culture of continuous learning and improvement
- Conduct code reviews and provide constructive feedback to team members
- Optimize existing systems for improved performance and scalability
- Contribute to the evolution of our technology stack and development processes
- Participate in technical decision-making and help set the direction for our engineering efforts
- Stay up-to-date with emerging technologies and industry trends, recommending innovations when appropriate
- Troubleshoot and resolve complex technical issues in production environments
- Expert-level proficiency in Ruby and strong knowledge of Ruby on Rails framework
- 8-10+ years of software development experience, with a proven track record of leading complex projects
- Bachelor's degree in Computer Science, Software Engineering, or related field (or equivalent experience)
- Strong experience with web development technologies (HTML, CSS, JavaScript)
- Proficiency in database systems (e.g., PostgreSQL, MySQL) and version control systems (e.g., Git)
- Deep understanding of software design patterns, principles, and best practices
- Experience with test-driven development (TDD) and automated testing frameworks
- Knowledge of scalable and distributed systems architecture
- Familiarity with cloud computing platforms (e.g., AWS, Azure, GCP)
- Strong problem-solving skills and ability to architect complex software solutions
- Excellent communication and leadership abilities, with experience mentoring junior developers
- Experience working with Agile methodologies
- Ability to balance technical leadership with hands-on coding
- Passion for staying current with emerging technologies and industry trends
WILL BE A PLUS
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PERSONAL PROFILE
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