| name | optimizing-tauri-binary-size |
| description | Guides users through Tauri binary size optimization techniques to produce small, efficient desktop application bundles using Cargo profile settings and build configurations. |
Tauri Binary Size Optimization
This skill provides guidance on optimizing Tauri application binary sizes for production releases.
Why Tauri Produces Small Binaries
Tauri is designed from the ground up to produce minimal binaries:
- Native Webview: Uses the operating system's native webview instead of bundling Chromium (unlike Electron)
- Rust Backend: Compiles to efficient native code with no runtime overhead
- Tree Shaking: Only includes code that is actually used
- No V8 Engine: Leverages existing system components rather than bundling a JavaScript engine
Size Comparison
| Framework | Minimum Binary Size |
|---|
| Tauri | ~3-6 MB |
| Electron | ~120-180 MB |
| NW.js | ~80-100 MB |
The dramatic size difference comes from Tauri's architectural decision to use native system webviews rather than bundling a full browser engine.
Cargo.toml Optimization Settings
Configure release profile settings in src-tauri/Cargo.toml to minimize binary size.
Recommended Stable Toolchain Configuration
[profile.release]
codegen-units = 1
lto = true
opt-level = "s"
panic = "abort"
strip = true
Configuration Options Explained
| Option | Values | Description |
|---|
codegen-units | 1 | Reduces parallelism but allows LLVM to perform better whole-program optimization |
lto | true, "thin", "fat" | Link-time optimization; true or "fat" produces smallest binaries |
opt-level | "s", "z", "3" | "s" balances size/speed, "z" prioritizes size, "3" prioritizes speed |
panic | "abort" | Removes panic handler code, reducing binary size |
strip | true, "symbols", "debuginfo" | Removes symbols and debug information from binary |
Nightly Toolchain Options
For projects using the nightly Rust toolchain, additional optimizations are available:
[profile.release]
codegen-units = 1
lto = true
opt-level = "s"
panic = "abort"
strip = true
trim-paths = "all"
[profile.release.build-override]
opt-level = "s"
You can also set rustflags for additional control:
[profile.release]
rustflags = ["-Cdebuginfo=0", "-Zthreads=8"]
Tauri Build Configuration
Remove Unused Commands (Tauri 2.4+)
Tauri 2.4 introduced the ability to automatically remove code for commands not permitted in your Access Control List (ACL). Add this to tauri.conf.json:
{
"build": {
"removeUnusedCommands": true
}
}
This feature:
- Analyzes your ACL configuration
- Removes Tauri command handlers that are not allowed
- Reduces binary size without changing functionality
- Works automatically during release builds
Minimal Feature Set
Only enable Tauri features you actually need in src-tauri/Cargo.toml:
[dependencies]
tauri = { version = "2", features = ["macos-private-api"] }
Frontend Optimization
While this skill focuses on Rust/Tauri optimization, frontend bundle size also affects the final application:
- Use a bundler: Vite, webpack, or similar with tree shaking
- Code splitting: Load features on demand
- Minimize dependencies: Audit and remove unused npm packages
- Compress assets: Optimize images and other static assets
Build Commands
Standard Release Build
cd src-tauri
cargo tauri build --release
Using Nightly Toolchain
cd src-tauri
cargo +nightly tauri build --release
Check Binary Size
After building, check your binary size:
ls -lh src-tauri/target/release/bundle/macos/*.app/Contents/MacOS/*
ls -lh src-tauri/target/release/bundle/appimage/*.AppImage
dir src-tauri\target\release\bundle\msi\*.msi
Complete Example Configuration
Here is a complete src-tauri/Cargo.toml optimized for minimal binary size:
[package]
name = "my-tauri-app"
version = "0.1.0"
edition = "2021"
[dependencies]
tauri = { version = "2", features = [] }
serde = { version = "1", features = ["derive"] }
serde_json = "1"
[build-dependencies]
tauri-build = { version = "2", features = [] }
[profile.release]
codegen-units = 1
lto = true
opt-level = "s"
panic = "abort"
strip = true
[profile.release.package."*"]
opt-level = "s"
And corresponding tauri.conf.json:
{
"productName": "my-tauri-app",
"version": "0.1.0",
"identifier": "com.example.my-tauri-app",
"build": {
"removeUnusedCommands": true,
"beforeBuildCommand": "npm run build",
"frontendDist": "../dist"
},
"bundle": {
"active": true,
"targets": "all",
"icon": ["icons/icon.png"]
}
}
Optimization Trade-offs
| Setting | Size Impact | Build Time | Runtime Performance |
|---|
codegen-units = 1 | Smaller | Slower | Better |
lto = true | Smaller | Much slower | Better |
opt-level = "s" | Smaller | Similar | Slightly slower |
opt-level = "z" | Smallest | Similar | Slower |
panic = "abort" | Smaller | Faster | No unwinding |
strip = true | Smaller | Similar | No impact |
Troubleshooting
Binary Still Large
- Check for debug builds: Ensure you are using
--release flag
- Audit dependencies: Run
cargo tree to see dependency graph
- Check for duplicate dependencies: Different versions of same crate
- Verify strip is working: Use
file command to check for debug symbols
Build Failures with LTO
If lto = true causes build failures:
- Try
lto = "thin" as a fallback
- Ensure sufficient memory (LTO is memory-intensive)
- Update Rust toolchain to latest version
Nightly Features Not Working
Ensure nightly is installed and active:
rustup install nightly
rustup default nightly
References