Compile the browser-automation core for wasm32: lib/bin split, rt abstraction, injected CDP transport, embedding seams

cli/Cargo.toml

@@ -13,20 +13,15 @@ categories = ["command-line-utilities", "web-programming"]
 [dependencies]
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
-dirs = "5.0"
 base64 = "0.22"
 getrandom = "0.2"
-tokio = { version = "1", features = ["rt-multi-thread", "macros", "net", "io-util", "time", "sync", "signal", "process"] }
-tokio-tungstenite = { version = "0.24", features = ["rustls-tls-webpki-roots"] }
 futures-util = "0.3"
 url = "2"
 uuid = { version = "1", features = ["v4"] }
 image = "0.25"
-reqwest = { version = "0.12", default-features = false, features = ["json", "rustls-tls-webpki-roots", "stream"] }
 sha2 = "0.10"
 aes-gcm = "0.10"
 async-trait = "0.1"
-socket2 = "0.6"
 similar = "2"
 zip = { version = "8.2.0", default-features = false, features = ["deflate"] }
 time = { version = "0.3", features = ["formatting"] }
@@ -36,6 +31,23 @@ chrono = "0.4"
 urlencoding = "2"
 rust-embed = "8"
 
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+dirs = "5.0"
+tokio = { version = "1", features = ["rt-multi-thread", "macros", "net", "io-util", "time", "sync", "signal", "process"] }
+tokio-tungstenite = { version = "0.24", features = ["rustls-tls-webpki-roots"] }
+reqwest = { version = "0.12", default-features = false, features = ["json", "rustls-tls-webpki-roots", "stream"] }
+socket2 = "0.6"
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+tokio = { version = "1", features = ["macros", "sync"] }
+getrandom = { version = "0.2", features = ["js"] }
+uuid = { version = "1", features = ["v4", "js"] }
+dirs = "5.0"
+reqwest = { version = "0.12", default-features = false, features = ["json", "stream"] }
+wasm-bindgen = "0.2"
+wasm-bindgen-futures = "0.4"
+js-sys = "0.3"
+
 [target.'cfg(unix)'.dependencies]
 libc = "0.2"
 

cli/src/artifacts.rs

@@ -0,0 +1,65 @@
+//! Pluggable artifact persistence. Commands that produce files (screenshots,
+//! PDFs, HARs, diffs) write through [`write`] so library hosts without a real
+//! filesystem (e.g. wasm) can install their own writer via
+//! [`set_artifact_writer`]. When no writer is installed, [`write`] falls back
+//! to `std::fs::write`, preserving native CLI behavior.
+
+#[cfg(not(target_arch = "wasm32"))]
+mod imp {
+    use std::sync::OnceLock;
+
+    pub type ArtifactWriter = Box<dyn Fn(&str, &[u8]) -> Result<(), String> + Send + Sync>;
+
+    static WRITER: OnceLock<ArtifactWriter> = OnceLock::new();
+
+    /// Install a process-global artifact writer. Returns an error if a writer
+    /// was already installed.
+    pub fn set_artifact_writer(writer: ArtifactWriter) -> Result<(), String> {
+        WRITER
+            .set(writer)
+            .map_err(|_| "artifact writer already installed".to_string())
+    }
+
+    pub fn write(path: &str, bytes: &[u8]) -> Result<(), String> {
+        if let Some(writer) = WRITER.get() {
+            return writer(path, bytes);
+        }
+        std::fs::write(path, bytes).map_err(|e| format!("Failed to write {}: {}", path, e))
+    }
+}
+
+#[cfg(target_arch = "wasm32")]
+mod imp {
+    use std::cell::RefCell;
+
+    pub type ArtifactWriter = Box<dyn Fn(&str, &[u8]) -> Result<(), String>>;
+
+    thread_local! {
+        static WRITER: RefCell<Option<ArtifactWriter>> = const { RefCell::new(None) };
+    }
+
+    /// Install a process-global artifact writer. Returns an error if a writer
+    /// was already installed.
+    pub fn set_artifact_writer(writer: ArtifactWriter) -> Result<(), String> {
+        WRITER.with(|w| {
+            let mut slot = w.borrow_mut();
+            if slot.is_some() {
+                return Err("artifact writer already installed".to_string());
+            }
+            *slot = Some(writer);
+            Ok(())
+        })
+    }
+
+    pub fn write(path: &str, bytes: &[u8]) -> Result<(), String> {
+        WRITER.with(|w| match w.borrow().as_ref() {
+            Some(writer) => writer(path, bytes),
+            None => Err(format!(
+                "cannot write {}: no artifact writer installed on this platform",
+                path
+            )),
+        })
+    }
+}
+
+pub use imp::{set_artifact_writer, write, ArtifactWriter};

cli/src/commands.rs

@@ -61,14 +61,21 @@ impl ParseError {
 }
 
 pub fn gen_id() -> String {
-    format!(
-        "r{}",
-        std::time::SystemTime::now()
-            .duration_since(std::time::UNIX_EPOCH)
-            .unwrap()
-            .as_micros()
-            % 1000000
-    )
+    format!("r{}", now_micros() % 1000000)
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+fn now_micros() -> u128 {
+    std::time::SystemTime::now()
+        .duration_since(std::time::UNIX_EPOCH)
+        .unwrap()
+        .as_micros()
+}
+
+// SystemTime::now is unsupported and panics on wasm32-unknown-unknown.
+#[cfg(target_arch = "wasm32")]
+fn now_micros() -> u128 {
+    (js_sys::Date::now() * 1000.0) as u128
 }
 
 /// Normalize browser navigation inputs while preserving schemes Chrome can

cli/src/connection.rs

@@ -7,6 +7,7 @@ use std::hash::{Hash, Hasher};
 use std::io::{BufRead, BufReader, Read, Write};
 use std::net::TcpStream;
 use std::path::PathBuf;
+#[cfg(any(unix, windows))]
 use std::process::{Command, Stdio};
 use std::thread;
 use std::time::{Duration, Instant};
@@ -183,6 +184,11 @@ pub fn cleanup_stale_files(session: &str) {
 /// so we don't mis-clean a live daemon owned by a different uid. Only ESRCH
 /// ("no such process") is treated as dead.
 pub fn is_pid_alive(pid: u32) -> bool {
+    #[cfg(not(any(unix, windows)))]
+    {
+        let _ = pid;
+        false
+    }
     #[cfg(unix)]
     unsafe {
         if libc::kill(pid as i32, 0) == 0 {
@@ -397,6 +403,11 @@ pub fn resolve_port(session: &str) -> u16 {
 }
 
 pub fn daemon_ready(session: &str) -> bool {
+    #[cfg(not(any(unix, windows)))]
+    {
+        let _ = session;
+        false
+    }
     #[cfg(unix)]
     {
         let socket_path = get_socket_path(session);
@@ -465,6 +476,7 @@ pub struct DaemonOptions<'a> {
     pub plugins: Option<&'a str>,
 }
 
+#[cfg(any(unix, windows))]
 fn apply_daemon_env(cmd: &mut Command, session: &str, opts: &DaemonOptions) {
     cmd.env("AGENT_BROWSER_DAEMON", "1")
         .env("AGENT_BROWSER_SESSION", session);
@@ -704,6 +716,7 @@ fn daemon_version_matches(session: &str) -> bool {
 }
 
 /// Kill a running daemon by reading its PID file and sending a kill signal.
+#[cfg_attr(not(any(unix, windows)), allow(unused_variables))]
 fn kill_stale_daemon(session: &str) {
     // Remove the socket first so no new connections reach the old daemon
     #[cfg(unix)]
@@ -780,6 +793,7 @@ fn stop_existing_daemon_for_restart(session: &str) {
     }
 }
 
+#[cfg_attr(not(any(unix, windows)), allow(unused_variables, unused_mut))]
 pub fn ensure_daemon(session: &str, opts: &DaemonOptions) -> Result<DaemonResult, String> {
     let mut restarted = false;
 
@@ -980,11 +994,18 @@ pub fn ensure_daemon(session: &str, opts: &DaemonOptions) -> Result<DaemonResult
     );
     #[cfg(windows)]
     let endpoint_info = format!("port: 127.0.0.1:{}", resolve_port(session));
+    #[cfg(not(any(unix, windows)))]
+    let endpoint_info = "no daemon endpoint on this platform".to_string();
 
     Err(format!("Daemon failed to start ({})", endpoint_info))
 }
 
 fn connect(session: &str) -> Result<Connection, String> {
+    #[cfg(not(any(unix, windows)))]
+    {
+        let _ = session;
+        Err("daemon connections are not supported on this platform".to_string())
+    }
     #[cfg(unix)]
     {
         let socket_path = get_socket_path(session);

cli/src/install.rs

@@ -1,9 +1,12 @@
+#[cfg(not(target_arch = "wasm32"))]
 use crate::color;
 use std::fs;
 use std::io::{self, Write};
 use std::path::{Path, PathBuf};
+#[cfg(not(target_arch = "wasm32"))]
 use std::process::{exit, Command, ExitStatus, Stdio};
 
+#[cfg(not(target_arch = "wasm32"))]
 const LAST_KNOWN_GOOD_URL: &str =
     "https://googlechromelabs.github.io/chrome-for-testing/last-known-good-versions-with-downloads.json";
 
@@ -98,6 +101,10 @@ pub fn find_installed_chrome() -> Option<PathBuf> {
     None
 }
 
+#[cfg_attr(
+    not(any(target_os = "macos", target_os = "linux", target_os = "windows")),
+    allow(unused_variables)
+)]
 fn chrome_binary_in_dir(dir: &Path) -> Option<PathBuf> {
     #[cfg(target_os = "macos")]
     {
@@ -151,6 +158,7 @@ fn chrome_binary_in_dir(dir: &Path) -> Option<PathBuf> {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn platform_key() -> &'static str {
     #[cfg(all(target_os = "macos", target_arch = "aarch64"))]
     {
@@ -182,6 +190,7 @@ fn platform_key() -> &'static str {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 async fn fetch_download_url() -> Result<(String, String), String> {
     let client = http_client()?;
     let resp = client
@@ -226,6 +235,7 @@ async fn fetch_download_url() -> Result<(String, String), String> {
     Ok((version, url))
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn format_reqwest_error(e: &reqwest::Error) -> String {
     let mut msg = e.to_string();
     let mut source = std::error::Error::source(e);
@@ -236,6 +246,7 @@ fn format_reqwest_error(e: &reqwest::Error) -> String {
     msg
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn http_client() -> Result<reqwest::Client, String> {
     reqwest::Client::builder()
         .user_agent(format!("agent-browser/{}", env!("CARGO_PKG_VERSION")))
@@ -245,6 +256,7 @@ fn http_client() -> Result<reqwest::Client, String> {
         .map_err(|e| format!("Failed to create HTTP client: {}", format_reqwest_error(&e)))
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 async fn download_bytes(url: &str) -> Result<Vec<u8>, String> {
     let client = http_client()?;
     let max_retries = 3;
@@ -332,6 +344,7 @@ async fn download_bytes(url: &str) -> Result<Vec<u8>, String> {
     Err(last_err)
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn extract_zip(bytes: Vec<u8>, dest: &Path) -> Result<(), String> {
     fs::create_dir_all(dest).map_err(|e| format!("Failed to create directory: {}", e))?;
 
@@ -397,6 +410,7 @@ fn extract_zip(bytes: Vec<u8>, dest: &Path) -> Result<(), String> {
     Ok(())
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 pub fn run_install(with_deps: bool) {
     if cfg!(all(target_os = "linux", target_arch = "aarch64")) {
         eprintln!(
@@ -497,6 +511,7 @@ pub fn run_install(with_deps: bool) {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn install_status_result(status: io::Result<ExitStatus>) -> Result<(), String> {
     match status {
         Ok(s) if s.success() => Ok(()),
@@ -510,6 +525,7 @@ fn install_status_result(status: io::Result<ExitStatus>) -> Result<(), String> {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn report_install_status(status: io::Result<ExitStatus>) {
     match install_status_result(status) {
         Ok(()) => {
@@ -530,6 +546,7 @@ fn report_install_status(status: io::Result<ExitStatus>) {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn apt_dependency_specs() -> Vec<(&'static str, Option<&'static str>)> {
     vec![
         ("libxcb-shm0", None),
@@ -572,6 +589,7 @@ fn apt_dependency_specs() -> Vec<(&'static str, Option<&'static str>)> {
     ]
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn resolve_apt_deps_with<F>(mut package_exists: F) -> Vec<&'static str>
 where
     F: FnMut(&str) -> bool,
@@ -589,10 +607,12 @@ where
         .collect()
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn resolve_apt_deps() -> Vec<&'static str> {
     resolve_apt_deps_with(package_exists_apt)
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn install_linux_deps() {
     println!("{}", color::cyan("Installing system dependencies..."));
 
@@ -783,6 +803,7 @@ fn install_linux_deps() {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn which_exists(cmd: &str) -> bool {
     #[cfg(unix)]
     {
@@ -806,6 +827,7 @@ fn which_exists(cmd: &str) -> bool {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 fn package_exists_apt(pkg: &str) -> bool {
     Command::new("apt-cache")
         .arg("show")

cli/src/lib.rs

@@ -0,0 +1,24 @@
+pub mod artifacts;
+#[cfg(not(target_arch = "wasm32"))]
+pub mod chat;
+pub mod color;
+pub mod commands;
+pub mod connection;
+#[cfg(not(target_arch = "wasm32"))]
+pub mod doctor;
+pub mod flags;
+pub mod install;
+#[cfg(not(target_arch = "wasm32"))]
+pub mod mcp;
+pub mod native;
+pub mod output;
+pub mod plugins;
+pub mod read;
+pub mod rt;
+#[cfg(not(target_arch = "wasm32"))]
+pub mod skills;
+#[cfg(test)]
+pub mod test_utils;
+#[cfg(not(target_arch = "wasm32"))]
+pub mod upgrade;
+pub mod validation;