diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index eb32953..a7e5e28 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -45,15 +45,17 @@ jobs:
         job:
           # https://github.com/actions/runner-images
           # Linux
+          - { target: aarch64-unknown-linux-musl, os: ubuntu-24.04 }
           - { target: arm-unknown-linux-musleabihf, os: ubuntu-24.04 }
           - { target: x86_64-unknown-linux-musl, os: ubuntu-24.04 }
           - { target: i686-unknown-linux-musl, os: ubuntu-24.04 }
           # OS X
-          - { target: aarch64-apple-darwin, os: macos-14 }
+          - { target: aarch64-apple-darwin, os: macos-15 }
+          - { target: x86_64-apple-darwin, os: macos-15-intel }
           # Windows
-          - { target: i686-pc-windows-msvc, os: windows-2022 }
-          - { target: x86_64-pc-windows-gnu, os: windows-2022 }
-          - { target: x86_64-pc-windows-msvc, os: windows-2022 }
+          - { target: aarch64-pc-windows-msvc, os: windows-11-arm }
+          - { target: x86_64-pc-windows-msvc, os: windows-2025 }
+          - { target: i686-pc-windows-msvc, os: windows-2025 }
     env:
       BUILD_CMD: cargo
     steps:
diff --git a/Cargo.lock b/Cargo.lock
index 4bb050b..f44c7e2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -498,6 +498,18 @@ dependencies = [
  "simd-adler32",
 ]
 
+[[package]]
+name = "filetime"
+version = "0.2.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bc0505cd1b6fa6580283f6bdf70a73fcf4aba1184038c90902b92b3dd0df63ed"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "libredox",
+ "windows-sys 0.60.2",
+]
+
 [[package]]
 name = "firefly-types"
 version = "0.7.1"
@@ -521,6 +533,7 @@ dependencies = [
  "data-encoding",
  "directories",
  "firefly-types",
+ "flate2",
  "hound",
  "image",
  "libflate",
@@ -531,6 +544,7 @@ dependencies = [
  "serde_json",
  "serialport",
  "sha2",
+ "tar",
  "toml",
  "ureq",
  "wasm-encoder",
@@ -540,9 +554,9 @@ dependencies = [
 
 [[package]]
 name = "flate2"
-version = "1.0.35"
+version = "1.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c936bfdafb507ebbf50b8074c54fa31c5be9a1e7e5f467dd659697041407d07c"
+checksum = "bfe33edd8e85a12a67454e37f8c75e730830d83e313556ab9ebf9ee7fbeb3bfb"
 dependencies = [
  "crc32fast",
  "miniz_oxide",
@@ -809,6 +823,7 @@ checksum = "c0ff37bd590ca25063e35af745c343cb7a0271906fb7b37e4813e8f79f00268d"
 dependencies = [
  "bitflags 2.9.0",
  "libc",
+ "redox_syscall",
 ]
 
 [[package]]
@@ -882,9 +897,9 @@ checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
 
 [[package]]
 name = "miniz_oxide"
-version = "0.8.3"
+version = "0.8.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b8402cab7aefae129c6977bb0ff1b8fd9a04eb5b51efc50a70bea51cda0c7924"
+checksum = "1fa76a2c86f704bdb222d66965fb3d63269ce38518b83cb0575fca855ebb6316"
 dependencies = [
  "adler2",
  "simd-adler32",
@@ -1435,6 +1450,17 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "tar"
+version = "0.4.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d863878d212c87a19c1a610eb53bb01fe12951c0501cf5a0d65f724914a667a"
+dependencies = [
+ "filetime",
+ "libc",
+ "xattr",
+]
+
 [[package]]
 name = "thiserror"
 version = "1.0.69"
@@ -1935,6 +1961,16 @@ version = "0.46.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f17a85883d4e6d00e8a97c586de764dabcc06133f7f1d55dce5cdc070ad7fe59"
 
+[[package]]
+name = "xattr"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32e45ad4206f6d2479085147f02bc2ef834ac85886624a23575ae137c8aa8156"
+dependencies = [
+ "libc",
+ "rustix 1.0.7",
+]
+
 [[package]]
 name = "zerocopy"
 version = "0.7.35"
diff --git a/Cargo.toml b/Cargo.toml
index 85a0622..1495e9d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,6 +36,8 @@ data-encoding = "2.9.0"
 directories = "6.0.0"
 # Serialize app config into meta file in the ROM
 firefly-types = { version = "0.7.1" }
+# Read gz archives (to install emulator).
+flate2 = "1.1.5"
 # Decode wav files
 hound = "3.5.1"
 # Parse PNG images
@@ -58,6 +60,8 @@ serde_json = "1.0.149"
 serialport = "4.8.1"
 # Calculate file checksum
 sha2 = "0.10.9"
+# Read gz archives (to install emulator).
+tar = "0.4.44"
 # Deserialize firefly.toml
 toml = "0.9.8"
 # Download remote files (`url` field in `firefly.toml`)
diff --git a/src/args.rs b/src/args.rs
index 40ca40b..ca9f734 100644
--- a/src/args.rs
+++ b/src/args.rs
@@ -216,6 +216,10 @@ pub struct NewArgs {
 
 #[derive(Debug, Parser)]
 pub struct EmulatorArgs {
+    /// Download the latest emulator release.
+    #[arg(long, default_value_t = false)]
+    pub update: bool,
+
     /// Arguments to pass into the emulator.
     pub args: Vec<String>,
 }
diff --git a/src/cli.rs b/src/cli.rs
index 0bf4dc6..d587707 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -6,13 +6,13 @@ use std::path::PathBuf;
 pub fn run_command(vfs: PathBuf, command: &Commands) -> anyhow::Result<()> {
     use Commands::*;
     match command {
-        Postinstall => cmd_postinstall(),
+        Postinstall => cmd_postinstall(&vfs),
         Build(args) => cmd_build(vfs, args),
         Export(args) => cmd_export(&vfs, args),
         Import(args) => cmd_import(&vfs, args),
         New(args) => cmd_new(args),
         Test(args) => cmd_test(args),
-        Emulator(args) => cmd_emulator(args),
+        Emulator(args) => cmd_emulator(&vfs, args),
         Badges(args) => cmd_badges(&vfs, args),
         Boards(args) => cmd_boards(&vfs, args),
         Inspect(args) => cmd_inspect(&vfs, args),
diff --git a/src/commands/emulator.rs b/src/commands/emulator.rs
index e9f2bc4..e22f536 100644
--- a/src/commands/emulator.rs
+++ b/src/commands/emulator.rs
@@ -1,70 +1,86 @@
 use crate::args::EmulatorArgs;
 use crate::langs::check_output;
 use anyhow::{Context, Result, bail};
+use flate2::read::GzDecoder;
+use std::fs::File;
+use std::path::Path;
 use std::process::Command;
+use tar::Archive;
 
-pub fn cmd_emulator(args: &EmulatorArgs) -> Result<()> {
-    let executed_dev = run_dev(args)?;
-    if executed_dev {
-        return Ok(());
-    }
-    let bins = [
-        "./firefly_emulator",
-        "./firefly_emulator.exe",
-        "firefly_emulator",
-        "firefly_emulator.exe",
-        "firefly-emulator",
-        "firefly-emulator.exe",
-    ];
-    for bin in bins {
-        if binary_exists(bin) {
-            println!("running {bin}...");
-            let output = Command::new(bin).args(&args.args).output()?;
-            check_output(&output).context("run emulator")?;
-            return Ok(());
-        }
+pub fn cmd_emulator(vfs: &Path, args: &EmulatorArgs) -> Result<()> {
+    #[cfg(target_os = "windows")]
+    const BINARY_NAME: &str = "firefly-emulator.exe";
+    #[cfg(not(target_os = "windows"))]
+    const BINARY_NAME: &str = "firefly-emulator";
+
+    // TODO(@orsinium): always use the global vfs.
+    let bin_path = vfs.join(BINARY_NAME);
+    if args.update || !bin_path.exists() {
+        println!("⏳️ downloading emulator...");
+        download_emulator(&bin_path).context("download emulator")?;
     }
-    bail!("emulator not installed");
+    println!("⌛ running...");
+    let output = Command::new(bin_path).args(&args.args).output()?;
+    check_output(&output).context("run emulator")?;
+    Ok(())
 }
 
-fn run_dev(args: &EmulatorArgs) -> Result<bool> {
-    // Check common places where firefly repo might be clonned.
-    // If found, run the dev version using cargo.
-    let Some(base_dirs) = directories::BaseDirs::new() else {
-        return Ok(false);
-    };
-    if !binary_exists("cargo") {
-        return Ok(false);
+fn download_emulator(bin_path: &Path) -> Result<()> {
+    // Send HTTP request.
+    let url = get_release_url().context("get latest release URL")?;
+    let resp = ureq::get(&url).call().context("send HTTP request")?;
+    let body = resp.into_body().into_reader();
+
+    // Extract archive.
+    if url.ends_with(".tar.gz") || url.ends_with(".tgz") {
+        let tar = GzDecoder::new(body);
+        let mut archive = Archive::new(tar);
+        let vfs = bin_path.parent().unwrap();
+        archive.unpack(vfs).context("extract binary")?;
+    } else {
+        bail!("unsupported archive format")
     }
-    let home = base_dirs.home_dir();
-    let paths = [
-        home.join("Documents").join("firefly"),
-        home.join("ff").join("firefly"),
-        home.join("github").join("firefly"),
-        home.join("firefly"),
-    ];
-    for dir_path in paths {
-        let cargo_path = dir_path.join("Cargo.toml");
-        if !cargo_path.is_file() {
-            continue;
-        }
-        println!("running dev version from {}...", dir_path.to_str().unwrap());
-        let output = Command::new("cargo")
-            .arg("run")
-            .arg("--")
-            .args(&args.args)
-            .current_dir(dir_path)
-            .output()?;
-        check_output(&output).context("run emulator")?;
-        return Ok(true);
+
+    // chmod.
+    #[cfg(unix)]
+    {
+        use std::os::unix::fs::PermissionsExt;
+        let file = File::open(bin_path).context("open file")?;
+        let mut perm = file.metadata().context("read file meta")?.permissions();
+        perm.set_mode(0o700);
+        std::fs::set_permissions(bin_path, perm).context("set permissions")?;
     }
-    Ok(false)
+
+    Ok(())
 }
 
-fn binary_exists(bin: &str) -> bool {
-    let output = Command::new(bin).arg("--help").output();
-    let Ok(output) = output else {
-        return false;
+fn get_release_url() -> Result<String> {
+    #[cfg(target_os = "windows")]
+    const SUFFIX: &str = "x86_64-pc-windows-msvc.tgz";
+    #[cfg(target_os = "macos")]
+    const SUFFIX: &str = "aarch64-apple-darwin.tgz";
+    #[cfg(target_os = "linux")]
+    const SUFFIX: &str = "x86_64-unknown-linux-gnu.tgz";
+
+    let version = get_latest_version()?;
+    let repo = "https://github.com/firefly-zero/firefly-emulator-bin";
+    Ok(format!(
+        "{repo}/releases/latest/download/firefly-emulator-v{version}-{SUFFIX}"
+    ))
+}
+
+fn get_latest_version() -> Result<String> {
+    let url = "https://github.com/firefly-zero/firefly-emulator-bin/releases/latest";
+    let req = ureq::get(url);
+    let req = req.config().max_redirects(0).build();
+    let resp = req.call()?;
+    if resp.status() != 302 {
+        bail!("unexpected status code: {}", resp.status());
+    }
+    let Some(loc) = resp.headers().get("Location") else {
+        bail!("no redirect Location found in response");
     };
-    output.status.success()
+    let loc = loc.to_str()?;
+    let version = loc.split('/').next_back().unwrap();
+    Ok(version.to_owned())
 }
diff --git a/src/commands/postinstall.rs b/src/commands/postinstall.rs
index f6129cb..4fe42d7 100644
--- a/src/commands/postinstall.rs
+++ b/src/commands/postinstall.rs
@@ -4,9 +4,18 @@ use std::{
     path::{Path, PathBuf},
 };
 
-pub fn cmd_postinstall() -> Result<()> {
-    let path = move_self()?;
-    create_alias(&path)?;
+pub fn cmd_postinstall(vfs: &Path) -> Result<()> {
+    let path = move_self().context("move binary")?;
+    delete_alias().context("delete old alias")?;
+    create_alias(&path).context("create alias")?;
+
+    // While CLI is released (and so is supposed to be updated)
+    // more often than emulator, most people update CLI only when
+    // we announce "the big release" which includes a new emulator.
+    // So, it's safe to assume that when we update CLI,
+    // emulator also needs to be updated (most of the time).
+    remove_emulator(vfs);
+
     Ok(())
 }
 
@@ -37,7 +46,13 @@ fn move_self_to(new_path: &Path) -> Result<()> {
         bail!("the binary is execute not by its path");
     }
     let new_path = new_path.join("firefly_cli");
-    std::fs::rename(old_path, new_path).context("move binary")?;
+
+    let res = std::fs::rename(&old_path, &new_path);
+    // Rename fails if src and dst on different mount points.
+    if res.is_err() {
+        std::fs::copy(&old_path, &new_path).context("copy binary")?;
+        _ = std::fs::remove_file(&old_path);
+    }
     Ok(())
 }
 
@@ -50,6 +65,17 @@ fn create_alias(dir_path: &Path) -> Result<()> {
     Ok(())
 }
 
+fn delete_alias() -> Result<()> {
+    let paths = load_paths();
+    for path in &paths {
+        let bin_path = path.join("ff");
+        if bin_path.is_file() {
+            std::fs::remove_file(bin_path)?;
+        }
+    }
+    Ok(())
+}
+
 #[cfg(unix)]
 fn create_alias_unix(dir_path: &Path) -> Result<()> {
     let old_path = dir_path.join("firefly_cli");
@@ -62,6 +88,14 @@ fn create_alias_unix(dir_path: &Path) -> Result<()> {
 fn find_writable_path() -> Option<PathBuf> {
     let paths = load_paths();
 
+    // Find a path that already has the old firefly_cli binary.
+    for path in &paths {
+        let bin_path = path.join("firefly_cli");
+        if bin_path.is_file() {
+            return Some(path.clone());
+        }
+    }
+
     // Prefer writable paths in the user home directory.
     if let Some(home) = std::env::home_dir() {
         for path in &paths {
@@ -147,6 +181,13 @@ fn add_path_to(profile: &Path, path: &Path) -> Result<()> {
     Ok(())
 }
 
+fn remove_emulator(vfs: &Path) {
+    let path = vfs.join("firefly-emulator");
+    _ = std::fs::remove_file(path);
+    let path = vfs.join("firefly-emulator.exe");
+    _ = std::fs::remove_file(path);
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/repl_helper.rs b/src/repl_helper.rs
index 43a4259..0bcf9e7 100644
--- a/src/repl_helper.rs
+++ b/src/repl_helper.rs
@@ -16,13 +16,36 @@ impl Helper {
         let mut hints = Vec::new();
         let cmds = [
             // commands
-            "build", "export", "import", "vfs", "cheat", "monitor", "catalog",
-            //
+            "build",
+            "export",
+            "import",
+            "new",
+            "emulator",
+            "test",
+            "badges",
+            "boards",
+            "vfs",
+            "runtime",
+            "inspect",
+            "shots",
+            "name",
+            "catalog",
             // subcommands
-            "new", "add", "pub", "priv", "rm", "list", "show",
-            //
+            "cheat",
+            "monitor",
+            "logs",
+            "screenshot",
+            "launch",
+            "restart",
+            "exit",
+            "id",
             // aliases
-            "install", "generate", "remove", "app", "author", "ls",
+            "install",
+            "generate",
+            "remove",
+            "app",
+            "author",
+            "ls",
         ];
         for cmd in cmds {
             let h = CommandHint(cmd.to_string());