chore: Add license header enforcement to all source files

.github/copilot-instructions.md

@@ -26,7 +26,7 @@ Before creating **any** commit, run:
 cargo xtask check
 ```
 
-This executes, in order: `fmt → clippy → deny → test → build`. Work is **not done** until this passes cleanly. If it fails, fix every reported issue before proceeding. No exceptions.
+This executes, in order: `license-headers → fmt → clippy → deny → test → build`. Work is **not done** until this passes cleanly. If it fails, fix every reported issue before proceeding. No exceptions.
 
 ---
 
@@ -83,6 +83,19 @@ Every decision — API design, data structure choice, algorithm, error path —
 - Types are `PascalCase`, functions are `snake_case`, constants are `SCREAMING_SNAKE_CASE`.
 - `cargo fmt --all` is the sole formatting authority — never override or disable it.
 
+### License header
+
+Every source file (`.rs`, `.ts`, `.js`, `.cs`, `.h`, `.proto`) **must** start with:
+
+```
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+```
+
+followed by a blank line before any code. `cargo xtask check` enforces this. Run `cargo xtask license-headers --fix` to add missing headers automatically.
+
+Files excluded from the check: `.html`, `.css`, `.json`, `.yml`, `.xml`, and auto-generated files (e.g. `webui_ffi.h`).
+
 ### Dependencies
 - Keep them minimal. Prefer the standard library. Before adding a crate, justify why std doesn't suffice.
 - Every dependency must pass `cargo deny check` (license allowlist + security advisories).
@@ -158,6 +171,8 @@ The `docs/` directory is a VitePress site for external developers consuming WebU
 | Format | `cargo xtask fmt` |
 | Lint | `cargo xtask clippy` |
 | License & advisory audit | `cargo xtask deny` |
+| License headers check | `cargo xtask license-headers` |
+| License headers fix | `cargo xtask license-headers --fix` |
 | Tests (workspace) | `cargo xtask test` |
 | Build (workspace) | `cargo xtask build` |
 | Test a single crate | `cargo test -p webui-parser` (or any crate name) |
@@ -265,6 +280,7 @@ Before finishing any task, confirm **all** of these:
 - [ ] No new recursion or regex in core paths.
 - [ ] No new `unwrap`/`expect` in library code.
 - [ ] No unnecessary allocations introduced; buffers reused where possible.
+- [ ] Every new source file has the license header (`// Copyright (c) Microsoft Corporation.` / `// Licensed under the MIT license.`).
 - [ ] FFI changes include `# Safety` docs and never panic across the boundary.
 - [ ] Proto schema changes prioritize performance and are cascade-tested.
 - [ ] New dependencies use `workspace = true` and pass `cargo deny check`.

crates/webui-cli/src/commands/build.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use anyhow::{Context, Result};
 use clap::Args;
 use expand_tilde::expand_tilde;

crates/webui-cli/src/commands/common.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use clap::Args;
 use std::path::PathBuf;
 pub use webui::CssStrategy;

crates/webui-cli/src/commands/inspect.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use anyhow::{Context, Result};
 use clap::Args;
 use expand_tilde::expand_tilde;

crates/webui-cli/src/commands/mod.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 pub mod build;
 pub mod common;
 pub mod inspect;

crates/webui-cli/src/commands/serve.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use actix_web::{web, App, HttpRequest, HttpResponse, HttpServer};
 use anyhow::{Context, Result};
 use clap::Args;

crates/webui-cli/src/main.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 mod commands;
 mod utils;
 

crates/webui-cli/src/utils/mod.rs

@@ -1 +1,4 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 pub mod output;

crates/webui-cli/src/utils/output.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 pub fn header(title: &str) {
     eprintln!(
         "\n  {} {}\n",

crates/webui-discovery/src/cache.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Component discovery cache for avoiding repeated filesystem traversal.
 //!
 //! Caches discovered component data at `~/.webui/cache/components/` and

crates/webui-discovery/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! External component discovery for the WebUI framework.
 //!
 //! Discovers components from npm packages and local filesystem paths.

crates/webui-discovery/src/npm.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! npm package resolution for external component discovery.
 //!
 //! Resolves npm packages from `node_modules/` using Node.js-style upward

crates/webui-expressions/benches/expressions_bench.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use criterion::{criterion_group, criterion_main, Criterion};
 use serde_json::json;
 use std::hint::black_box;

crates/webui-expressions/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! WebUI expression evaluation module.
 //!
 //! This module handles the evaluation of condition expressions in WebUI templates.

crates/webui-ffi/build.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 extern crate cbindgen;
 
 use std::env;

crates/webui-ffi/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! WebUI FFI (Foreign Function Interface) for interoperability with other languages.
 //!
 //! This crate provides C-compatible APIs for the WebUI handler to be used from languages

crates/webui-ffi/tests/csharp/WebUIFFITest.cs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 // Integration tests for the webui-ffi shared library via P/Invoke.
 //
 // Usage (macOS):

crates/webui-ffi/tests/ffi_test.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Integration tests for the webui-ffi C ABI.
 //!
 //! These tests call every `#[no_mangle] extern "C"` function through the

crates/webui-handler/benches/handler_bench.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion, Throughput};
 use serde_json::json;
 use serde_json::Value;

crates/webui-handler/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! WebUI Handler implementation for Rust.
 //!
 //! This crate provides functionality to process and render WebUI protocols

crates/webui-handler/src/plugin.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Handler plugin trait and built-in plugin implementations.
 //!
 //! The plugin system is framework-agnostic — WebUI provides lifecycle hooks

crates/webui-handler/src/plugin/fast.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! FAST Hydration plugin for the WebUI handler.
 //!
 //! Injects HTML comment markers and data attributes that enable client-side

crates/webui-handler/src/route_handler.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Route component inventory management for incremental route rendering.
 //!
 //! These helpers walk the normal render fragment graph. The request-aware path is

crates/webui-handler/src/route_matcher.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Iterative path template matcher for server-side route resolution.
 //!
 //! Matches request paths against route path templates without regex.

crates/webui-node/build.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 fn main() {
     napi_build::setup();
 }

crates/webui-node/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Node.js native addon for the WebUI framework via napi-rs.
 //!
 //! Provides high-performance server-side rendering by compiling the Rust

crates/webui-parser/benches/parser_bench.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion, Throughput};
 use std::hint::black_box;
 use webui_parser::{plugin::FastParserPlugin, CssStrategy, HtmlParser};

crates/webui-parser/src/component_registry.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Component registry for WebUI framework.
 //!
 //! This module manages the registry of web components used in the application.

crates/webui-parser/src/condition_parser.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Parser for WebUI condition expressions.
 //!
 //! This module handles parsing condition expressions used in if directives.

crates/webui-parser/src/css_parser.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! CSS parser for WebUI components.
 //!
 //! This module uses tree-sitter-css to parse CSS files

crates/webui-parser/src/error.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Error handling for the WebUI parser.
 
 use std::fmt;

crates/webui-parser/src/handlebars_parser.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use crate::Result;
 use webui_protocol::WebUIFragment;
 

crates/webui-parser/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Directive parser for WebUI template directives.
 //!
 //! This module handles parsing WebUI-specific directives like <for>, <if>, etc.

crates/webui-parser/src/plugin/fast.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! FAST parser plugin for the WebUI parser.
 //!
 //! Tracks component definitions during HTML parsing and generates `<f-template>`

crates/webui-parser/src/plugin/mod.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Parser plugin trait and built-in plugin implementations.
 //!
 //! The plugin system is framework-agnostic — WebUI provides parsing hooks

crates/webui-parser/src/route_parser.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Route element parsing for `<route>` directives.
 //!
 //! Parses `<route path="..." component="..." ...>` elements into

crates/webui-protocol/benches/protocol_bench.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion, Throughput};
 use std::collections::HashMap;
 use std::hint::black_box;

crates/webui-protocol/build.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use std::io::Result;
 
 fn main() -> Result<()> {

crates/webui-protocol/proto/webui.proto

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 syntax = "proto3";
 
 package webui;

crates/webui-protocol/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! WebUI Protocol implementation.
 //!
 //! This crate defines the protocol used by the WebUI framework for cross-platform

crates/webui-state/benches/state_bench.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion};
 use serde_json::json;
 use std::hint::black_box;

crates/webui-state/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 extern crate serde_json;
 
 use serde_json::Value;

crates/webui-test-utils/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Test utilities for WebUI framework.
 //!
 //! This crate provides testing helpers and should only be used in test code.

crates/webui-wasm/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! WebAssembly bindings for the WebUI framework.
 //!
 //! This crate exposes the WebUI rendering pipeline to JavaScript via `wasm-bindgen`,

crates/webui/benches/contact_book_bench.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! End-to-end benchmark for the contact-book-manager example application.
 //!
 //! Compiles the real contact-book-manager templates into a protocol binary at

crates/webui/src/error.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Error types for the WebUI library.
 
 use thiserror::Error;

crates/webui/src/lib.rs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 //! Programmatic API for the WebUI build-time rendering framework.
 //!
 //! This crate provides the core build, render, and inspection APIs

docs/.vitepress/config.js

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 export default {
   title: "WebUI Framework",
   description: "Native HTML Templating for Every Platform",

docs/.vitepress/theme/index.js

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 import DefaultTheme from 'vitepress/theme'
 import './custom.css'
 

dotnet/src/Microsoft.WebUI/NativeBindings.cs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 using System;
 using System.Reflection;
 using System.Runtime.InteropServices;

dotnet/src/Microsoft.WebUI/WebUIException.cs

@@ -1,3 +1,6 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
 using System;
 
 namespace Microsoft.WebUI;