Senior C#/.NET Developer

We are seeking a Senior C#/.NET Developer to work on the control software of a high-precision optical metrology tool used in semiconductor manufacturing. The product has been in development and in field deployment for roughly ten years, and the mandate is to improve reliability and maintainability while driving a significantly stronger modularisation of the software architecture. The software is non-connected (no cloud) and is tested directly against physical hardware, with Azure DevOps as the toolchain.

Responsibilities

• Design, develop, test, and maintain tool control software in C# and .NET
• Drive modularisation of a mature codebase without destabilizing a production system
• Build robust concurrent code, including multi-threading, locking and interlocking, and parallelism in .NET
• Apply TDD and strengthen automated testing, including tests that touch real hardware
• Conduct code reviews
• Mentor and coach mid-level developers
• Troubleshoot complex issues across the software and hardware boundary

Requirements

• Proficiency in C# and .NET with 3+ years of hands-on, senior-level experience on production systems
• Background in hardware-related development environments — code that has controlled, driven, or read from physical equipment
• Knowledge of object-oriented design, SOLID and design patterns, along with Clean Code principles
• Expertise in Test-Driven Development and ownership of automated test suites
• Skills in multi-threading, locking/interlocking, and parallelism in .NET
• Experience refactoring and modularising a long-lived legacy codebase
• Familiarity with mentoring and conducting code reviews
• English proficiency at B2 level or above

Nice to have

• Understanding of real-time systems and deterministic timing
• Competency in hardware integration such as motion control, sensors and actuators, or device drivers and instrument interfaces
• Qualifications in optical sensor data processing, including spectroscopy, interferometry, or imaging and signal processing
• Domain background in semiconductor, metrology, test and measurement, or precision instrumentation, industrial automation, or medical devices
• German language skills

We offer

• We gather like-minded people:
• • Top tech minds driving innovation in AI, cloud and digital platform modernization
  • Supportive team and agile, startup-like culture
  • Hybrid by design mode and opportunity to work remotely within Poland
  • Chance to work abroad for up to 60 days annually
  • Business-driven relocation opportunities
• We provide growth opportunities:
• • Career development programs
  • Thought leadership, mentoring, soft skills and well-being programs
  • Certification (Anthropic, Gemini, GCP, Azure, AWS)
  • English classes
• We cover it all:
• • Stable pay
  • Participation in the Employee Stock Purchase Plan with a 15% discount
  • Benefits package (health insurance, multisport, shopping vouchers)
  • Referral bonuses up to $2,000
  • Offices featuring entertainment and relaxation zones, table tennis and football, free snacks, coffee and more
  • Corporate, social and well-being events
• Please, note:
• • Benefits listed above are available to employees only
  • We are open for working with Contractors. Terms of B2B cooperation agreements are agreed individually
  • We will reach out to selected candidates exclusively

EPAM is global leader in AI transformation engineering and integrated consulting, serving Forbes Global 2000 companies and ambitious startups. With over thirty years of expertise in custom software, product and platform engineering, we empower our clients to become AI-Native enterprises, driving measurable value from innovation and digital investments.