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. ResponsibilitiesDesign, develop, test, and maintain tool control software in C# and . NETDrive modularisation of a mature codebase without destabilizing a production systemBuild robust concurrent code, including multi-threading, locking and interlocking, and parallelism in . NETApply TDD and strengthen automated testing, including tests that touch real hardwareConduct code reviewsMentor and coach mid-level developersTroubleshoot complex issues across the software and hardware boundaryRequirementsProficiency in C# and . NET with 3+ years of hands-on, senior-level experience on production systemsBackground in hardware-related development environments — code that has controlled, driven, or read from physical equipmentKnowledge of object-oriented design, SOLID and design patterns, along with Clean Code principlesExpertise in Test-Driven Development and ownership of automated test suitesSkills in multi-threading, locking/interlocking, and parallelism in . NETExperience refactoring and modularising a long-lived legacy codebaseFamiliarity with mentoring and conducting code reviewsEnglish proficiency at B2 level or aboveNice to haveUnderstanding of real-time systems and deterministic timingCompetency in hardware integration such as motion control, sensors and actuators, or device drivers and instrument interfacesQualifications in optical sensor data processing, including spectroscopy, interferometry, or imaging and signal processingDomain background in semiconductor, metrology, test and measurement, or precision instrumentation, industrial automation, or medical devicesGerman language skillsWe offerWe gather like-minded people: Top tech minds driving innovation in AI, cloud and digital platform modernizationSupportive team and agile, startup-like cultureHybrid by design mode and opportunity to work remotely within PolandChance to work abroad for up to 60 days annuallyBusiness-driven relocation opportunitiesWe provide growth opportunities: Career development programsThought leadership, mentoring, soft skills and well-being programsCertification (Anthropic, Gemini, GCP, Azure, AWS)English classesWe cover it all: Stable payParticipation in the Employee Stock Purchase Plan with a 15% discountBenefits package (health insurance, multisport, shopping vouchers)Referral bonuses up to $2,000Offices featuring entertainment and relaxation zones, table tennis and football, free snacks, coffee and moreCorporate, social and well-being eventsPlease, note: Benefits listed above are available to employees onlyWe are open for working with Contractors. Terms of B2B cooperation agreements are agreed individuallyWe will reach out to selected candidates exclusivelyEPAM 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.