Senior Software Engineer (.NET / Embedded)

We are seeking a Senior Software Engineer (.NET / Embedded) to work on the control software of a high-precision optical metrology tool used in semiconductor manufacturing. 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