diff --git a/README.md b/README.md
index c4066a45..ad75c12d 100644
--- a/README.md
+++ b/README.md
@@ -89,13 +89,27 @@ For chat and prompt to code features:
 
 ### Install
 
-You can install it via [Homebrew](http://brew.sh/):
+**One-line installer** — runs the bundled `install.sh` script which handles the download, moves the app to `/Applications`, and prints the remaining manual steps.
+
+> **Security note:** before piping any remote script to bash, you can review it first at [`install.sh`](install.sh).
+
+```bash
+bash <(curl -fsSL https://raw.githubusercontent.com/intitni/CopilotForXcode/main/install.sh)
+```
+
+Or, if you have already cloned the repository:
+
+```bash
+bash install.sh
+```
+
+Alternatively, you can install it via [Homebrew](http://brew.sh/) directly:
 
 ```bash
 brew install --cask copilot-for-xcode
 ```
 
-Or install it manually, by downloading the `Copilot for Xcode.app` from the latest [release](https://github.com/intitni/CopilotForXcode/releases).
+Or install it manually by downloading the `Copilot for Xcode.app` from the latest [release](https://github.com/intitni/CopilotForXcode/releases).
 
 Please make sure the app is inside the Applications folder.
 
diff --git a/install.sh b/install.sh
new file mode 100755
index 00000000..02e4ca6b
--- /dev/null
+++ b/install.sh
@@ -0,0 +1,170 @@
+#!/usr/bin/env bash
+# install.sh — Install Copilot for Xcode on macOS
+#
+# Usage:
+#   bash install.sh
+#
+# The script will:
+#   1. Verify prerequisites (macOS 12+, Xcode installed)
+#   2. Install the app via Homebrew cask when available, or download the
+#      latest release from GitHub otherwise
+#   3. Launch the app once so it registers its background launch agent
+#   4. Print step-by-step instructions for the manual post-install tasks
+#      (enabling the Source Editor Extension and granting Accessibility access)
+
+set -euo pipefail
+
+# ── color helpers ─────────────────────────────────────────────────────────────
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+CYAN='\033[0;36m'
+BOLD='\033[1m'
+RESET='\033[0m'
+
+info()    { echo -e "${CYAN}[info]${RESET}  $*"; }
+success() { echo -e "${GREEN}[ok]${RESET}    $*"; }
+warn()    { echo -e "${YELLOW}[warn]${RESET}  $*"; }
+error()   { echo -e "${RED}[error]${RESET} $*" >&2; }
+step()    { echo -e "\n${BOLD}$*${RESET}"; }
+
+# ── constants ─────────────────────────────────────────────────────────────────
+APP_NAME="Copilot for Xcode"
+APP_BUNDLE="Copilot for Xcode.app"
+APP_PATH="/Applications/${APP_BUNDLE}"
+BREW_CASK="copilot-for-xcode"
+GITHUB_RELEASES="https://api.github.com/repos/intitni/CopilotForXcode/releases/latest"
+MIN_MACOS_MAJOR=12   # macOS Monterey
+
+# ── prerequisite checks ───────────────────────────────────────────────────────
+step "1/4  Checking prerequisites"
+
+# macOS version
+os_version=$(sw_vers -productVersion 2>/dev/null || echo "0.0")
+os_major=$(echo "$os_version" | cut -d. -f1)
+if [[ "$os_major" -lt "$MIN_MACOS_MAJOR" ]]; then
+    error "${APP_NAME} requires macOS Monterey (12) or later."
+    error "Current version: ${os_version}"
+    exit 1
+fi
+success "macOS ${os_version} — compatible"
+
+# Xcode installed (look for the app bundle or xcode-select path)
+if ! xcode-select -p &>/dev/null || [[ ! -d "$(xcode-select -p)" ]]; then
+    error "Xcode does not appear to be installed."
+    error "Install Xcode from the Mac App Store, then re-run this script."
+    exit 1
+fi
+success "Xcode found at $(xcode-select -p)"
+
+# ── installation ──────────────────────────────────────────────────────────────
+step "2/4  Installing ${APP_NAME}"
+
+if [[ -d "$APP_PATH" ]]; then
+    success "${APP_NAME} is already installed at ${APP_PATH}"
+elif command -v brew &>/dev/null; then
+    info "Homebrew detected — installing via cask …"
+    brew install --cask "$BREW_CASK"
+    success "Installed via Homebrew"
+else
+    warn "Homebrew not found — falling back to manual download."
+
+    # Fetch the download URL of the latest stable release asset
+    # Note: the 'latest' endpoint intentionally skips pre-releases and drafts.
+    info "Fetching latest release information from GitHub …"
+    if command -v jq &>/dev/null; then
+        asset_url=$(
+            curl -fsSL "$GITHUB_RELEASES" \
+            | jq -r '.assets[] | select(.name | endswith(".zip")) | .browser_download_url' \
+            | head -1
+        )
+    else
+        asset_url=$(
+            curl -fsSL "$GITHUB_RELEASES" \
+            | grep '"browser_download_url"' \
+            | grep '\.zip"' \
+            | head -1 \
+            | sed 's/.*"browser_download_url": "\(.*\)"/\1/'
+        )
+    fi
+
+    if [[ -z "$asset_url" ]]; then
+        error "Could not determine the download URL from GitHub."
+        error "Please download ${APP_NAME} manually from:"
+        error "  https://github.com/intitni/CopilotForXcode/releases"
+        exit 1
+    fi
+
+    tmp_dir=$(mktemp -d)
+    zip_path="${tmp_dir}/CopilotForXcode.zip"
+
+    info "Downloading ${APP_NAME} …"
+    curl -fL --progress-bar "$asset_url" -o "$zip_path"
+
+    info "Extracting …"
+    unzip -q "$zip_path" -d "$tmp_dir"
+
+    extracted_app=$(find "$tmp_dir" -maxdepth 3 -name "*.app" | head -1)
+    # maxdepth 3 covers: archive root / optional top-level dir / .app bundle
+    if [[ -z "$extracted_app" ]]; then
+        error "Could not find the .app bundle inside the downloaded archive."
+        rm -rf "$tmp_dir"
+        exit 1
+    fi
+
+    info "Moving ${APP_BUNDLE} to /Applications …"
+    # Remove a stale copy if present (handles re-install after failed attempt)
+    [[ -d "$APP_PATH" ]] && rm -rf "$APP_PATH"
+    cp -R "$extracted_app" "$APP_PATH"
+    rm -rf "$tmp_dir"
+
+    success "Installed to ${APP_PATH}"
+fi
+
+# ── launch the app once ───────────────────────────────────────────────────────
+step "3/4  Launching ${APP_NAME}"
+
+info "Opening ${APP_NAME} to register its background service …"
+open -a "$APP_PATH"
+
+# Give the app a moment to start before we print the next instructions
+sleep 3
+success "${APP_NAME} has been opened"
+
+# ── post-install instructions ─────────────────────────────────────────────────
+step "4/4  Post-install steps (manual)"
+
+os_minor=$(echo "$os_version" | cut -d. -f2)
+
+echo ""
+echo -e "${BOLD}A) Enable the Source Editor Extension${RESET}"
+if [[ "$os_major" -ge 15 ]]; then
+    echo "   Open: System Settings → General → Login Items & Extensions"
+    echo "   Click 'Xcode Source Editor' and tick 'Copilot for Xcode'."
+elif [[ "$os_major" -eq 14 ]]; then
+    echo "   Open: System Settings → Privacy & Security → Extensions"
+    echo "   Click 'Xcode Source Editor' and tick 'Copilot'."
+else
+    echo "   Open: System Preferences → Extensions"
+    echo "   Tick 'Copilot' under 'Xcode Source Editor'."
+fi
+
+echo ""
+echo -e "${BOLD}B) Grant Accessibility permission${RESET}"
+echo "   Open: System Settings → Privacy & Security → Accessibility"
+echo "   Add 'CopilotForXcodeExtensionService.app' to the list."
+echo "   (Click 'Reveal Extension App in Finder' inside ${APP_NAME} to locate it.)"
+
+echo ""
+echo -e "${BOLD}C) Set up your AI provider${RESET}"
+echo "   • GitHub Copilot: navigate to 'Service → GitHub Copilot' in the host app,"
+echo "     click 'Install' then 'Sign In'."
+echo "   • Codeium: navigate to 'Service → Codeium', click 'Install' then 'Sign In'."
+echo "   • OpenAI / other chat models: navigate to 'Service → Chat Model'."
+
+echo ""
+echo -e "${BOLD}D) (Optional) Set up key bindings in Xcode${RESET}"
+echo "   Xcode → Settings → Key Bindings → search for 'copilot'"
+
+echo ""
+success "Installation complete! Enjoy ${APP_NAME} 🎉"