ZipDrive

Mount ZIP and RAR archives as native Windows drives — browse and stream files instantly.

ZipDrive turns ZIP and RAR archives into a browsable Windows drive letter. Unlike Windows Explorer's built-in "Open as folder" (which silently extracts entire archives to temp), ZipDrive decompresses incrementally in 10MB chunks — the first byte is available in ~50ms, while the rest extracts in the background. Open a 5GB video from an archive and it starts playing immediately.

Why ZipDrive?

	Windows Built-in	Other Mount Tools	ZipDrive
Real drive letter	No (folder view only)	Varies	Yes — works in every app
Upfront extraction	Yes (hidden temp copy)	Often required	No — incremental chunked extraction, first byte in ~50ms
Multi-archive mount	No	Rarely	Yes — entire directories of ZIPs
Single-file mount	No	Varies	Yes — drag one ZIP/RAR onto the exe
Large file support (>4 GB)	Limited	Varies	Full ZIP64 support
International filenames	Mojibake common	Varies	Auto charset detection (Shift-JIS, GBK, EUC-KR, ...)
RAR support	No	Varies	RAR4 & RAR5 (non-solid) via SharpCompress
Concurrent access	Single-threaded	Varies	100+ simultaneous readers, validated by 12-hour soak test
Open source	No	Rarely	Yes — clean architecture, extensible

Key Features

• Virtual Drive Mounting — Mount a directory of archives or a single archive file as a Windows drive letter
• Multi-Format Support — ZIP (with ZIP64) and RAR (RAR4/RAR5 non-solid) via a pluggable provider architecture
• Chunked Incremental Extraction — Decompresses in 10MB chunks; first byte in ~50ms, background extraction continues
• Dual-Tier Caching — Small files (< 50MB) in memory, large files on disk via NTFS sparse files — independent LRU eviction per tier
• Automatic Charset Detection — Correctly displays non-Latin filenames via statistical encoding detection (Shift-JIS, GBK, EUC-KR, etc.)
• Dynamic Reload — Add or remove archive files from the directory while ZipDrive is running; changes appear automatically
• Sibling Prefetch (opt-in) — Proactively warms nearby files in a single sequential pass. Disabled by default
• Thundering Herd Prevention — Lock-free cache hits with per-key deduplication across 100+ concurrent readers
• OpenTelemetry Observability — Opt-in metrics, tracing, and structured logging with Aspire Dashboard support
• Drag-and-Drop Launch — Drag a folder or a single archive file onto ZipDrive.exe — no command line needed

Prerequisites

• Windows x64 (DokanNet is Windows-specific)
• Dokany v2.3.1.1000 — Dokan file system driver
• .NET 10.0 Runtime — Required to run (SDK required for building from source)

Quick Start

Drag and Drop

Drag a folder onto ZipDrive.exe — all ZIP and RAR files in that folder are mounted at R:\.

Drag a single ZIP or RAR file onto ZipDrive.exe — just that archive is mounted.

Command Line

# Mount all archives in a directory
ZipDrive.exe --Mount:ArchiveDirectory="D:\my-zips" --Mount:MountPoint="R:\"

# Mount a single archive file
ZipDrive.exe --Mount:ArchiveDirectory="D:\Downloads\game.zip"

Building from Source

dotnet build ZipDrive.slnx
dotnet run --project src/ZipDrive.Cli/ZipDrive.Cli.csproj -- --Mount:ArchiveDirectory="D:\my-zips"

Publishing a Single-File Executable

dotnet publish src/ZipDrive.Cli/ZipDrive.Cli.csproj -c Release -r win-x64 --self-contained false -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true -o ./publish

Output: publish/ZipDrive.exe (~74 MB) + publish/appsettings.jsonc

Configuration

All settings are in appsettings.jsonc (shipped alongside the executable). Command-line arguments override with --Section:Key=Value syntax.

Mount Options

Setting	Default	Description
Mount:MountPoint	R:\	Drive letter to mount
Mount:ArchiveDirectory	(required)	Path to a directory of archives or a single archive file
Mount:MaxDiscoveryDepth	6	Maximum directory depth for archive discovery
Mount:ShortCircuitShellMetadata	true	Skip Windows shell metadata probes to avoid unnecessary ZIP parsing
Mount:FallbackEncoding	utf-8	Fallback encoding for non-UTF8 filenames (e.g., shift_jis, gb2312)
Mount:EncodingConfidenceThreshold	0.5	Minimum confidence (0.0-1.0) for charset auto-detection
Mount:UseFolderNameAsVolumeLabel	false	Use the archive directory folder name as the drive's volume label
Mount:DynamicReloadQuietPeriodSeconds	5	Delay before processing file system changes (debounce)
Mount:HideUnsupportedArchives	false	Hide unsupported archives (e.g., solid RAR) instead of showing them with a warning

Cache Options

Setting	Default	Description
Cache:MemoryCacheSizeMb	2048	Memory tier capacity (MB)
Cache:DiskCacheSizeMb	10240	Disk tier capacity (MB)
Cache:SmallFileCutoffMb	50	Files smaller than this go to memory; larger go to disk
Cache:ChunkSizeMb	10	Chunk size for incremental disk-tier extraction (~50ms first-byte latency)
Cache:TempDirectory	System temp	Directory for disk-tier cache files
Cache:DefaultTtlMinutes	30	Cache entry time-to-live
Cache:EvictionCheckIntervalSeconds	10	Background maintenance sweep interval

Prefetch Options (under Cache:Prefetch)

Prefetch is disabled by default because background software (Explorer, antivirus, indexers) can trigger cascading I/O. Enable only if you control what accesses the drive.

Setting	Default	Description
Cache:Prefetch:Enabled	false	Master on/off switch
Cache:Prefetch:OnRead	true	Prefetch siblings when a file is opened (active once Enabled=true)
Cache:Prefetch:OnListDirectory	false	Prefetch on directory listing — keep off to avoid cascade
Cache:Prefetch:FileSizeThresholdMb	10	Max file size for prefetch candidates
Cache:Prefetch:MaxFiles	20	Max siblings per prefetch span
Cache:Prefetch:FillRatioThreshold	0.80	Min density (wanted bytes / span bytes)

OpenTelemetry

Opt-in. Set the endpoint to enable metrics and tracing:

ZipDrive.exe --OpenTelemetry:Endpoint="http://localhost:18889"

Visualize with Aspire Dashboard: docker run -p 18888:18888 -p 18889:18889 mcr.microsoft.com/dotnet/aspire-dashboard, then open http://localhost:18888.

Architecture

ZipDrive follows Clean Architecture with strict dependency rules:

Presentation (CLI)
  -> Application (orchestration)
    -> Domain (interfaces, models — zero external dependencies)
  <- Infrastructure (caching, ZIP reader, RAR reader, Dokan adapter)

Data Flow

DokanNet ReadFile("R:\archive.zip\folder\file.txt")
  -> Archive Prefix Tree: resolve path -> archive key + internal path
  -> Structure Cache: get/build parsed Central Directory
  -> File Content Cache: get/decompress file data (memory or chunked disk tier)
  -> Stream: seek + read -> return to DokanNet

Project Structure

src/
  ZipDrive.Domain/                        Core interfaces and models (zero dependencies)
  ZipDrive.Application/                   Path resolution, archive discovery, VFS orchestration
  ZipDrive.Infrastructure.Archives.Zip/   Streaming ZIP reader with ZIP64 support
  ZipDrive.Infrastructure.Archives.Rar/   RAR4/RAR5 provider via SharpCompress
  ZipDrive.Infrastructure.Caching/        Generic cache, chunked extraction, dual-tier routing
  ZipDrive.Infrastructure.FileSystem/     DokanNet adapter, mount lifecycle, user notices
  ZipDrive.Cli/                           Entry point, DI, OpenTelemetry wiring

Testing

dotnet test                                     # Run all tests (~480 tests)
dotnet test --filter "FullyQualifiedName~ThunderingHerd"   # Run specific tests
dotnet test tests/ZipDrive.EnduranceTests       # Endurance soak (~72s default)
ENDURANCE_DURATION_HOURS=12 dotnet test tests/ZipDrive.EnduranceTests  # Extended

Concurrency model formally verified with TLA+ (specs/formal/). See Concurrency Strategy for details.

Design Documents

Detailed design docs in src/Docs/: Caching | Chunked Extraction | Concurrency | ZIP Reader | VFS | Multi-Format | Dynamic Reload

Technology Stack

• .NET 10.0 / C# 13 — DokanNet — SharpCompress — Spectre.Console — OpenTelemetry — Serilog — UtfUnknown — XUnit + FluentAssertions — BenchmarkDotNet

License

See LICENSE for details.