Senior Windows Agent Engineer

DOU Polska; Województwo mazowieckie; On-site; PLN 190,000 - 280,000; Full time

Job summary

DOU Polska seeks an experienced software engineer to develop Windows endpoint agents that run at scale and manage fleets of devices. You will work on low-level OS observation, interop between managed and native code, and secure communication with cloud services.

The role emphasizes stability, auditability, and minimal user impact, across large deployments with strong security requirements. Fluency in English is required.

Qualifications

• 6+ years of production software experience for Windows endpoints or long-running unattended software
• Deep understanding of Windows internals: processes, threads, memory, sessions, services, tokens, privileges, Windows security model
• Strong command of C# and .NET
• Solid production experience with C++
• Hands-on managed-to-native interoperability
• Experience with Win32, ETW, WMI, and performance counters
• Ability to profile and optimize CPU, memory, and I/O for long-running, low-footprint software
• Experience with crash dumps and traces for root-cause analysis
• Understanding of concurrency in long-running software
• Proven ability to deliver, sign and upgrade software at fleet scale
• Strong security discipline when running with elevated privileges
• Experience with AI-assisted and agentic coding tools
• Proven ability to critically review AI-generated code
• English – Advanced
• Production experience with Swift
• macOS systems programming: launchd, XPC, extensions, privacy controls, notarization

Responsibilities

• Build the low-level layer that observes the operating system in managed and native code
• Keep the agent's resource footprint minimal so end users never notice it
• Ensure reliable and secure endpoint-to-cloud communication, including offline operation
• Implement endpoint actions that change device state safely with audit trail
• Extend on-device detection to identify known issues and investigate them
• Build the on-device user experience presented by the agent
• Own agent installation, upgrades and rollbacks across very large device fleets
• Diagnose field failures, including conflicts with endpoint security products
• Turn architectural direction into production-quality implementations with minimal supervision

Skills

Windows internals

C#

C++

Interop

Win32

ETW

WMI

Performance counters

Crash dumps

Concurrency

Self-recovering

Fleet scale

AI-assisted tools

AI-generated code review

English – Advanced

Swift

macOS systems programming

Job description

Our Customer

Our customer is an international product company that builds enterprise software for monitoring and managing large fleets of corporate devices. Its products help IT teams keep workplace endpoints stable, secure and performing well at scale.

Your Tasks

• Build the low-level layer that observes the operating system, in both managed and native code
• Keep the agent’s resource footprint minimal so that end users never notice it
• Ensure reliable and secure endpoint-to-cloud communication, including on unstable networks and during offline operation
• Implement endpoint actions that change device state safely, predictably and with a clear audit trail
• Extend on-device detection to automatically identify and investigate known issues
• Build the on-device user experience presented by the agent
• Own agent installation, upgrades and rollbacks across very large device fleets
• Diagnose field failures, including conflicts with endpoint security products
• Turn architectural direction into complete, production-quality implementations with minimal supervision

Required Experience And Skills

• 6+ years of experience building production software focused on Windows systems, endpoint agents or long-running unattended software
• Deep understanding of Windows internals, including processes, threads, memory, sessions, services, tokens, privileges and the Windows security model
• Strong command of C# and .NET
• Solid production experience with C++
• Hands-on experience with managed-to-native interoperability
• Hands-on experience with native Windows interfaces, including Win32, ETW, WMI and performance counters
• Proven ability to profile and optimize CPU, memory and I/O usage for continuously running, low-footprint software
• Hands-on experience with root-cause analysis using crash dumps and traces
• Solid understanding of concurrency in long-running software
• Proven ability to build reliable, self-recovering software
• Hands-on experience delivering, signing and upgrading software at fleet scale
• Strong security discipline when developing software that runs with elevated privileges
• Hands-on production experience with AI-assisted and agentic coding tools
• Proven ability to critically review AI-generated code
• English – Advanced

Would Be a Plus

• Production experience with Swift
• Hands-on experience with macOS systems programming, including launchd daemons, XPC, system extensions, privacy controls and notarization