Lertaro

Overview of Lertaro

What it is

Lertaro is an ultra-lightweight, high-performance, extensible global search and productivity launcher for Windows, built on .NET 10 (WPF). It serves as a modern, open-source alternative to Listary and Everything, indexing local drives via the NTFS USN Journal and $MFT for near-instant, low-resource search. The project is hosted on GitHub under the MIT license.

Key features

• NTFS/ReFS USN Change Journal and $MFT low-level indexing, with a lightweight background service that keeps the index in sync in real time, plus FAT32/exFAT monitoring and network share caching.
• fzf-style fuzzy search with multi-keyword jump matching, directory path tokens, prefix/suffix/exact/exclude operators, and non-ASCII pinyin alias transliteration.
• Three window modes: a quick popup window, a full main window, and an inline bar that automatically docks into native Open/Save file dialogs and major file managers (File Explorer, Total Commander, Directory Opus, OneCommander).
• Actions menu (Ctrl+O) with native Shell right-click integration and QuickLook file preview (Alt+P).
• Instant disk space treemap that visually explores indexed disk usage without rescanning, with drill-down into oversized folders and cleanup actions.
• Open plugin SDK with .NET 10 C# contracts for custom search providers, aliases, actions, columns, and previews, plus compatibility with Flow Launcher community plugins.
• 3-process isolation (SYSTEM background service, user-mode WPF UI, and UIPI-bypassing hook helper), 100% local with zero telemetry.

Use cases

Lertaro is intended for users who need fast, low-resource local file search and desktop productivity launching on Windows. It is suitable for searching files across NTFS, ReFS, FAT32, exFAT, and network shares; organizing and acting on indexed files through an actions menu or QuickLook previews; and visually analyzing disk space usage through an instant treemap. The plugin SDK also makes it extensible for custom search providers, aliases, actions, and previews.

Getting started

Download the latest release from the homepage or directly:

• x64: Installer (Lertaro-Setup.exe) or Portable (Lertaro-Portable.zip)
• ARM64: Installer (Lertaro-Setup-arm64.exe) or Portable (Lertaro-Portable-arm64.zip) For building from source, requirements include Windows 10/11, .NET 10 SDK, Visual Studio 2022 or JetBrains Rider, and optionally Inno Setup 7 for the installer. Use build_and_run.bat to rebuild and relaunch, or make.bat for Release builds. See the repository README for more details.

License and pricing

MIT License. Open source, no pricing.

Based on the project's public README and repository metadata.