feat: add browser/WASM support for bashkit

.gitignore

@@ -34,3 +34,6 @@ dist/
 
 # Node
 node_modules/
+
+# WASM build artifacts
+*.wasm

Cargo.toml

@@ -18,7 +18,9 @@ categories = ["command-line-utilities", "parser-implementations"]
 
 [workspace.dependencies]
 # Async runtime
-tokio = { version = "1", features = ["full"] }
+# Base features are WASM-compatible; crates needing more (rt-multi-thread, fs, net, process)
+# add them in their own Cargo.toml or via [target.'cfg(...)'.dependencies].
+tokio = { version = "1", features = ["sync", "macros", "io-util", "rt", "time"] }
 async-trait = "0.1"
 futures = "0.3"
 

crates/bashkit-bench/Cargo.toml

@@ -16,7 +16,7 @@ path = "src/main.rs"
 
 [dependencies]
 bashkit = { path = "../bashkit" }
-tokio.workspace = true
+tokio = { workspace = true, features = ["rt-multi-thread", "process"] }
 serde.workspace = true
 serde_json.workspace = true
 clap.workspace = true

crates/bashkit-eval/Cargo.toml

@@ -16,7 +16,7 @@ path = "src/main.rs"
 
 [dependencies]
 bashkit = { path = "../bashkit", features = ["scripted_tool"] }
-tokio.workspace = true
+tokio = { workspace = true, features = ["rt-multi-thread"] }
 serde.workspace = true
 serde_json.workspace = true
 clap.workspace = true

crates/bashkit-js/package.json

@@ -3,8 +3,15 @@
   "version": "0.1.10",
   "description": "Sandboxed bash interpreter for JavaScript/TypeScript",
   "main": "wrapper.js",
+  "browser": "bashkit.wasi-browser.js",
   "types": "wrapper.d.ts",
   "type": "module",
+  "exports": {
+    ".": {
+      "browser": "./bashkit.wasi-browser.js",
+      "default": "./wrapper.js"
+    }
+  },
   "license": "MIT",
   "repository": {
     "type": "git",
@@ -34,11 +41,17 @@
     "index.cjs",
     "index.d.ts",
     "index.d.cts",
-    "bashkit.*.node"
+    "bashkit.*.node",
+    "bashkit.wasi-browser.js",
+    "bashkit.wasi.cjs",
+    "bashkit.wasm32-wasi.wasm",
+    "wasi-worker.mjs",
+    "wasi-worker-browser.mjs"
   ],
   "scripts": {
     "build": "npm run build:napi && npm run build:cjs && npm run build:ts",
     "build:napi": "napi build --platform --release",
+    "build:wasm": "napi build --platform --target wasm32-wasip1-threads --release",
     "build:cjs": "node -e \"const fs=require('fs'); if(fs.existsSync('index.js')){fs.renameSync('index.js','index.cjs')}; if(fs.existsSync('index.d.ts')){fs.copyFileSync('index.d.ts','index.d.cts')}\"",
     "build:ts": "tsc",
     "artifacts": "napi artifacts",
@@ -49,6 +62,9 @@
     "type-check": "tsc --noEmit",
     "version": "napi version"
   },
+  "optionalDependencies": {
+    "@napi-rs/wasm-runtime": "^1.1.1"
+  },
   "devDependencies": {
     "@napi-rs/cli": "^3.0.0",
     "@types/node": "^25.5.0",

crates/bashkit-python/Cargo.toml

@@ -24,7 +24,7 @@ pyo3 = { workspace = true }
 pyo3-async-runtimes = { workspace = true }
 
 # Async runtime
-tokio = { workspace = true }
+tokio = { workspace = true, features = ["rt-multi-thread"] }
 
 # Serialization
 serde_json = { workspace = true }

crates/bashkit/Cargo.toml

@@ -134,3 +134,7 @@ required-features = ["realfs"]
 [[example]]
 name = "realfs_readwrite"
 required-features = ["realfs"]
+
+# Additional tokio features needed only on native (not WASM)
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+tokio = { version = "1", features = ["rt-multi-thread", "fs"] }

crates/bashkit/src/lib.rs

@@ -480,6 +480,7 @@ pub struct Bash {
     fs: Arc<dyn FileSystem>,
     interpreter: Interpreter,
     /// Parser timeout (stored separately for use before interpreter runs)
+    #[cfg(not(target_family = "wasm"))]
     parser_timeout: std::time::Duration,
     /// Maximum input script size in bytes
     max_input_bytes: usize,
@@ -503,13 +504,15 @@ impl Bash {
     pub fn new() -> Self {
         let fs: Arc<dyn FileSystem> = Arc::new(InMemoryFs::new());
         let interpreter = Interpreter::new(Arc::clone(&fs));
+        #[cfg(not(target_family = "wasm"))]
         let parser_timeout = ExecutionLimits::default().parser_timeout;
         let max_input_bytes = ExecutionLimits::default().max_input_bytes;
         let max_ast_depth = ExecutionLimits::default().max_ast_depth;
         let max_parser_operations = ExecutionLimits::default().max_parser_operations;
         Self {
             fs,
             interpreter,
+            #[cfg(not(target_family = "wasm"))]
             parser_timeout,
             max_input_bytes,
             max_ast_depth,
@@ -554,6 +557,7 @@ impl Bash {
             )));
         }
 
+        #[cfg(not(target_family = "wasm"))]
         let parser_timeout = self.parser_timeout;
         let max_ast_depth = self.max_ast_depth;
         let max_parser_operations = self.max_parser_operations;
@@ -568,50 +572,62 @@ impl Bash {
             "Parsing script"
         );
 
-        // Parse with timeout using spawn_blocking since parsing is sync
-        let parse_result = tokio::time::timeout(parser_timeout, async {
-            tokio::task::spawn_blocking(move || {
-                let parser =
-                    Parser::with_limits(&script_owned, max_ast_depth, max_parser_operations);
-                parser.parse()
+        // On WASM, tokio::task::spawn_blocking and tokio::time::timeout don't
+        // work (no blocking thread pool, timer driver unreliable). Parse inline.
+        #[cfg(target_family = "wasm")]
+        let ast = {
+            let parser = Parser::with_limits(&script_owned, max_ast_depth, max_parser_operations);
+            parser.parse()?
+        };
+
+        // On native targets, parse with timeout using spawn_blocking since
+        // parsing is sync and we don't want to block the async runtime.
+        #[cfg(not(target_family = "wasm"))]
+        let ast = {
+            let parse_result = tokio::time::timeout(parser_timeout, async {
+                tokio::task::spawn_blocking(move || {
+                    let parser =
+                        Parser::with_limits(&script_owned, max_ast_depth, max_parser_operations);
+                    parser.parse()
+                })
+                .await
             })
-            .await
-        })
-        .await;
-
-        let ast = match parse_result {
-            Ok(Ok(result)) => {
-                match &result {
-                    Ok(_) => {
-                        #[cfg(feature = "logging")]
-                        tracing::debug!(target: "bashkit::parser", "Parse completed successfully");
-                    }
-                    Err(_e) => {
-                        #[cfg(feature = "logging")]
-                        tracing::warn!(target: "bashkit::parser", error = %_e, "Parse error");
+            .await;
+
+            match parse_result {
+                Ok(Ok(result)) => {
+                    match &result {
+                        Ok(_) => {
+                            #[cfg(feature = "logging")]
+                            tracing::debug!(target: "bashkit::parser", "Parse completed successfully");
+                        }
+                        Err(_e) => {
+                            #[cfg(feature = "logging")]
+                            tracing::warn!(target: "bashkit::parser", error = %_e, "Parse error");
+                        }
                     }
+                    result?
+                }
+                Ok(Err(join_error)) => {
+                    #[cfg(feature = "logging")]
+                    tracing::error!(
+                        target: "bashkit::parser",
+                        error = %join_error,
+                        "Parser task failed"
+                    );
+                    return Err(Error::Parse(format!("parser task failed: {}", join_error)));
+                }
+                Err(_elapsed) => {
+                    #[cfg(feature = "logging")]
+                    tracing::error!(
+                        target: "bashkit::parser",
+                        timeout_ms = parser_timeout.as_millis() as u64,
+                        "Parser timeout exceeded"
+                    );
+                    return Err(Error::ResourceLimit(LimitExceeded::ParserTimeout(
+                        parser_timeout,
+                    )));
                 }
-                result?
-            }
-            Ok(Err(join_error)) => {
-                #[cfg(feature = "logging")]
-                tracing::error!(
-                    target: "bashkit::parser",
-                    error = %join_error,
-                    "Parser task failed"
-                );
-                return Err(Error::Parse(format!("parser task failed: {}", join_error)));
-            }
-            Err(_elapsed) => {
-                #[cfg(feature = "logging")]
-                tracing::error!(
-                    target: "bashkit::parser",
-                    timeout_ms = parser_timeout.as_millis() as u64,
-                    "Parser timeout exceeded"
-                );
-                return Err(Error::ResourceLimit(LimitExceeded::ParserTimeout(
-                    parser_timeout,
-                )));
             }
         };
 
@@ -1562,6 +1578,7 @@ impl BashBuilder {
             interpreter.set_history_file(hf);
         }
 
+        #[cfg(not(target_family = "wasm"))]
         let parser_timeout = limits.parser_timeout;
         let max_input_bytes = limits.max_input_bytes;
         let max_ast_depth = limits.max_ast_depth;
@@ -1571,6 +1588,7 @@ impl BashBuilder {
         Bash {
             fs,
             interpreter,
+            #[cfg(not(target_family = "wasm"))]
             parser_timeout,
             max_input_bytes,
             max_ast_depth,

examples/README.md

@@ -101,3 +101,18 @@ LangChain.js ReAct agent with `DynamicStructuredTool`.
 export OPENAI_API_KEY=sk-...
 node examples/langchain_agent.mjs
 ```
+
+### browser/
+
+Bashkit running in the browser via WebAssembly. A minimal terminal UI that
+lets you type bash commands and see output — all executed client-side in a
+sandboxed WASM interpreter.
+
+Requires `Cross-Origin-Opener-Policy` and `Cross-Origin-Embedder-Policy`
+headers for `SharedArrayBuffer` support (Vite config handles this).
+
+```bash
+cd examples/browser
+npm install
+npm run dev
+```

examples/browser/README.md

@@ -0,0 +1,36 @@
+# Bashkit Browser Example
+
+A sandboxed Bash interpreter running entirely in the browser via WebAssembly.
+
+![Bashkit Browser Terminal](demo.png)
+
+## Quick Start
+
+```bash
+# Requires: rustup target add wasm32-wasip1-threads
+npm install
+npm start
+```
+
+`npm start` builds the WASM binary and starts the Vite dev server. Open http://localhost:5173.
+
+## How It Works
+
+Bashkit compiles to `wasm32-wasip1-threads` via [napi-rs](https://napi.rs). The browser loads the WASM binary through `@napi-rs/wasm-runtime`, which provides WASI preview1 support and a thread pool using Web Workers + SharedArrayBuffer.
+
+The terminal UI is a single `index.html` — no framework, no build step beyond WASM compilation.
+
+## Scripts
+
+| Command | Description |
+|---------|-------------|
+| `npm start` | Build WASM + start dev server |
+| `npm run dev` | Start dev server (WASM must already be built) |
+| `npm run build` | Build WASM + production bundle |
+| `npm run build:wasm` | Build WASM only |
+
+## Requirements
+
+- Node.js >= 18
+- Rust with `wasm32-wasip1-threads` target
+- Browser with SharedArrayBuffer support (requires COOP/COEP headers, configured in `vite.config.js`)