find-my-files

Instant file-name search for Windows, built with a Rust engine and a native WinUI 3 UI.

Status: early development (pre-MVP). Nothing usable yet.

Project page: p4suta.github.io/find-my-files — overview in 日本語 / English

What it does

Windows-only, file names only, FOSS.

• Initial index by reading the NTFS $MFT directly (~seconds per volume)
• Real-time updates from the USN change journal — no filesystem watchers, no rescans
• Multithreaded SIMD substring scan over an in-memory index (~100 MB per million files)
• Pre-sorted indices: sorting a million results by name/size/date is instant
• Native WinUI 3: Mica, consistent dark theme, Per-Monitor V2 DPI (no blur on mixed-DPI setups)

What it deliberately does NOT do

Content/property indexing, tags, previews, FTP/HTTP servers, FAT/exFAT/network drives (initially). Indexing file names only is the reason it's fast. Feature creep is a non-goal.

Where did the admin prompt go?

Reading the NTFS Master File Table and USN journal requires elevated volume access. find-my-files splits that privilege off into a small Windows service (fmf-engine, LocalSystem with stripped privileges); the UI runs unprivileged and talks to it over a locked-down named pipe (same-user only — see docs/SECURITY.md for the threat model).

just service-install   # register + harden (elevated, once)
just service-start

Without the service installed, the app offers to relaunch elevated and runs the engine in-process instead (--engine=inproc, the original MVP mode).

By default, hidden/system files — and everything under hidden/system folders ($Recycle.Bin contents, pagefile.sys, .git internals…) — are excluded from results. A toolbar toggle brings them back instantly (they stay indexed).

Known limitations: names with unpaired surrogates are searchable but displayed with replacement characters.

Building

Toolchain is pinned via mise (mise.toml), tasks run via just:

mise install        # rust + dotnet toolchains
just setup          # toolchain + git hooks (lefthook)
just build          # engine (cargo, release)
just test           # engine unit tests
just service-dev    # run the engine service in the foreground (elevated)
just index C:       # index a volume from the CLI (elevated terminal required)

The WinUI 3 app lives in app/ (from milestone M1 onward).

Architecture

WinUI 3 app (C#, unprivileged) ──named pipe──▶  fmf-service (Rust, LocalSystem)
   └─ IEngineClient boundary                       └─ fmf-core: $MFT scan, USN tailing,
       ├─ PipeEngineClient (default)                    in-memory index, query engine
       └─ FfiEngineClient ──P/Invoke──▶  fmf_engine.dll (in-proc fallback, elevated)

See docs/ARCHITECTURE.md for the FFI contract and docs/RESEARCH.md for the verified technical groundwork (MFT/USN APIs, prior art, performance baselines).

Documentation

• Design docs — architecture, ADRs, research, and the security model (rendered from docs/ with mdBook)
• API reference — Rust crate docs (rustdoc)

Both rebuild on every push to main; build them locally with just doc.

License

Apache-2.0