tauri-build

Active contributors: Lucas Fernandes Nogueira, Amr Bashir

Purpose

crates/tauri-build is what users [build-dependencies]-on. Their src-tauri/build.rs calls tauri_build::build(), which:

1. Parses tauri.conf.json and re-runs the build whenever it changes.
2. Resolves the application's ACL (capabilities × permissions) into a single Resolved blob and emits it to OUT_DIR for the runtime to consume.
3. Writes the Windows resource file (.rc) so the app picks up icon/version metadata.
4. Embeds the application manifest on Windows (DPI awareness, manifestv1 vs v6 common controls).
5. Generates Cargo metadata for mobile targets (cargo:rustc-link-search= and friends), and helps glob native libraries.
6. Optionally invokes tauri-codegen to embed assets early, before the main crate build runs.

Directory layout

crates/tauri-build/
├── Cargo.toml
├── src/
│   ├── lib.rs                     # 24,430 bytes: build() entry, Attributes, options
│   ├── acl.rs                     # 14.2 KB: resolve permissions+capabilities -> Resolved
│   ├── codegen/                   # internal calls into tauri-codegen
│   ├── manifest.rs                # tauri.conf.json → Cargo features
│   ├── mobile.rs                  # mobile target plumbing (Android NDK, iOS metal toolchain)
│   ├── static_vcruntime.rs
│   └── windows-app-manifest.xml
└── build.rs

Key abstractions

Type / function	File	Role
build / try_build	crates/tauri-build/src/lib.rs	Public entry. build() panics on error; try_build() returns Result.
Attributes	crates/tauri-build/src/lib.rs	Builder for opting in to extra behaviour (Windows app manifest, codegen pre-embedding, ACL options).
WindowsAttributes	crates/tauri-build/src/lib.rs	.rc content, manifest tweaks, app icon paths.
acl::resolve_acl	crates/tauri-build/src/acl.rs	Read every plugin's permissions/, the app's capabilities/, produce a Resolved.
manifest::*	crates/tauri-build/src/manifest.rs	Translate tauri.conf.json → Cargo cfg(...) and feature emissions.
mobile::*	crates/tauri-build/src/mobile.rs	Mobile-target globbing and tauri-android/ios bridge wiring.

How it works

graph TD
    UserBuild["src-tauri/build.rs<br/>(downstream app)"] -->|"tauri_build::build()"| Entry["lib.rs#build"]
    Entry --> ManifestOut["manifest::*<br/>cargo:rustc-cfg, features"]
    Entry --> ACLOut["acl::resolve_acl<br/>writes Resolved JSON to OUT_DIR"]
    Entry --> WinRC["WindowsAttributes -> embed .rc"]
    Entry --> CodegenStep["(optional) tauri-codegen::context_codegen"]
    ACLOut -->|read at runtime| TauriCore["tauri::ipc::RuntimeAuthority"]

The Resolved ACL written here is what tauri::generate_context! (via tauri-codegen) embeds into the binary. At runtime, RuntimeAuthority reads it.

The Windows manifest XML at crates/tauri-build/src/windows-app-manifest.xml is the default; WindowsAttributes::app_manifest lets users override it.

Cargo features

• codegen — pull in tauri-codegen so users can also do their asset embedding here.
• config-json5 / config-toml — accept alternative config formats.

Integration points

• Up: every Tauri downstream app's build.rs.
• Down: depends on tauri-utils (config types, ACL types) and optionally tauri-codegen.

Entry points for modification

Goal	Start here
New Windows manifest behaviour	crates/tauri-build/src/lib.rs (search WindowsAttributes) and windows-app-manifest.xml
Change ACL resolution rules	crates/tauri-build/src/acl.rs (mirrors runtime in crates/tauri/src/ipc/authority.rs)
Change a cfg emitted to user crates	crates/tauri-build/src/manifest.rs
Mobile NDK/Xcode globbing	crates/tauri-build/src/mobile.rs

See tauri-codegen for the embedding it triggers, and systems/acl-and-capabilities for the ACL story.