Patch Research Engineer

Come work at a place where innovation and teamwork come together to support the most exciting missions in the world! **About the Role** Qualys is looking for a detail-oriented Windows Patch Management Catalog Researcher to join the Patch Management product team. In this role, you will be responsible for building and maintaining a comprehensive, accurate patch catalog covering a wide range of third-party Windows software.   **Key Responsibilities** **Patch Catalog Research & Authoring** * Research, author, and maintain patch metadata for third-party Windows applications across a broad software catalog. * Identify new software releases, security updates, and version changes from vendor sources, changelogs, and security advisories (CVE/NVD). * Map vendor releases to structured metadata schemas, including version strings, download URLs, detection logic, and installation parameters. * Track software End-of-Life (EOL) dates and update catalog entries accordingly. **Windows Patching & Installation Knowledge** * Document and validate silent installation parameters for diverse installer types (MSI, NSIS EXE, InnoSetup, WiX, etc.). * Research and verify correct msiexec.exe flags, NSIS /S switches, and equivalent silent/unattended arguments per software. * Determine accurate reboot behavior (Yes / No / Maybe) per installer type and document exit codes (success, reboot-required). * Manually test patch installation in sandbox environments and verify detection logic post-install. **Detection Logic & Registry Research** * Research and validate Windows registry keys used to detect installed software versions (Uninstall hive, vendor-specific keys, DisplayVersion, etc.). * Identify and document file-based detection paths (FileVersion, ProductVersion attributes on key executables). * Understand the difference between 32-bit and 64-bit registry views (WOW6432Node) and apply correct detection architecture per installer variant. * Validate detection logic against fresh installs and upgrades across supported Windows versions. **Backend Patch Tool Understanding** * Understand how enterprise patch management platforms (e.g., Qualys Patch Management, SCCM, Ivanti, Adaptiva) discover, deploy, and verify patches. * Familiarity with how catalogs are consumed by patch engines — detection-before-install logic, supersedence evaluation, and deployment policy enforcement. **Required Skills & Qualifications** * 4-5 years of experience in Windows systems administration, patch management, or software packaging. * Strong understanding of Windows OS internals — registry structure, file system, user vs. system installation scopes, environment variables, and PATH management. * Hands-on experience with Windows patching tools (WSUS, SCCM/ConfigMgr, Ivanti, Qualys, Chocolatey, or equivalent). * Experience with manual patch installation — running MSI/EXE installers, using msiexec.exe with switches, repackaging software. * Solid understanding of installer technologies: MSI/WiX, NSIS, InnoSetup, Squirrel, and their silent install mechanisms. * Familiarity with the Windows registry and the ability to trace installation artifacts to their registry keys. **Nice to Have** * Experience building or maintaining a software patch catalog (Adaptiva, Chocolatey, ManageEngine, or similar). * Experience with Windows Installer (MSI) internals — product codes, upgrade codes, component tables. * Knowledge of ARM64 Windows platform nuances and multi-architecture software distribution. * Good understanding of Windows Update infrastructure (WUA, WSUS, CBS/SFC). * Scripting experience in Python or PowerShell.