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Mostman for macOS — Installation, Security & Command-Line Guide

Jan 22, 2026

Mostman for macOS — Installation, Security & Command-Line Guide

Mostman for macOS — Installation, Security & Command-Line Guide

Last updated: January 2026

This document provides a complete, transparent, and detailed explanation of everything macOS users may encounter when downloading, installing, and running Mostman on macOS.

It explicitly documents all security warnings, explains why they happen, and provides command-line instructions required to run Mostman today.

⚠️ Important: At the time of writing, macOS UI-based security approval may not function correctly on some systems. Command-line steps are the recommended and supported installation method until official Apple code signing and notarization are completed.

Overview

Mostman is a modern API development and automation tool designed for developers. On macOS, Mostman is distributed as:

  • Desktop Application (GUI)
  • Terminal UI (TUI)
  • Command-Line Interface (CLI)

Due to Apple's strict security model and the fact that Mostman is a newly released and unsigned application, macOS will show multiple security warnings during installation and execution.

These warnings do not indicate malware. They are expected behavior for unsigned software.

macOS Gatekeeper & Security Model

macOS uses Gatekeeper, XProtect, and System Integrity Protection (SIP) to restrict unknown applications.

Applications that are:

  • Not signed with an Apple Developer ID
  • Not notarized by Apple
  • Newly released

are blocked by default.

Common macOS Warnings You Will See

1. “Mostman cannot be opened because it is from an unidentified developer”

This dialog typically includes:

  • Cancel
  • Move to Trash

2. “Apple cannot check it for malicious software”

Text may include:

“Apple cannot check it for malicious software. This software needs to be updated.”

3. App opens and immediately closes

This may happen if Gatekeeper blocks execution silently.

Why These Warnings Appear

  • Mostman is not yet signed with an Apple Developer ID
  • The application is not notarized
  • Apple reputation systems have no prior data
  • Gatekeeper defaults to blocking execution

This is normal behavior for early-stage developer tools.

IMPORTANT: Use Command Line (Recommended Method)

Due to current macOS UI limitations, command-line execution is the reliable and supported approach.

Command-Line Installation & Execution

Step 1: Open Terminal

Use Terminal.app or any preferred terminal emulator.

Step 2: Make the binary executable

If you downloaded Mostman as a binary:

chmod +x mostman

or for app bundles:

chmod +x Mostman.app/Contents/MacOS/Mostman

Step 3: Remove quarantine attribute (CRITICAL)

macOS applies a quarantine flag to downloaded files.

Run:

xattr -dr com.apple.quarantine Mostman.app

or for CLI/TUI binaries:

xattr -d com.apple.quarantine mostman

This step is mandatory.

Step 4: Run Mostman from Terminal

CLI:

./mostman --help

TUI:

./mostman-tui

Desktop (GUI):

open Mostman.app

If UI fails to open, continue using CLI/TUI.

Why System Settings UI May Not Work

In some macOS versions:

  • “Open Anyway” does not appear
  • Security approval dialogs do not persist
  • Gatekeeper blocks silently

This is a known Apple behavior for unsigned apps.

Using Terminal bypasses UI inconsistencies safely.

Network & Permissions

Mostman:

  • Does not request system-wide permissions
  • Does not install background daemons
  • Uses network access only when you execute requests
  • Does not monitor your system

Verifying the Application

You can verify the binary:

codesign -dv --verbose=4 Mostman.app

Expected output:

code object is not signed at all

This is expected at this stage.

Why Mostman Is Safe

  • Built via reproducible CI pipelines
  • Distributed only via official domains
  • No obfuscation or hidden behavior
  • No auto-update background services
  • No privilege escalation

Why Code Signing & Notarization Are Not Yet Enabled

Apple requires:

  • Apple Developer Program membership
  • Legal entity verification
  • Time-consuming notarization process

These steps will be completed in future releases.

Once completed:

  • All Gatekeeper warnings will disappear
  • UI-based approval will work normally
  • Command-line workarounds will no longer be required

Future Changes (Important)

🚀 This process will change

In future versions:

  • Mostman will be fully signed
  • Notarized by Apple
  • Launchable without Terminal commands

This document will be updated accordingly.

Recommended User Guidance

Until signing is completed:

  • Use Terminal for execution
  • Follow the commands exactly
  • Ignore UI security dialogs
  • Trust only downloads from mostman.dev

Troubleshooting

App does not open

Run:

xattr -dr com.apple.quarantine Mostman.app

Permission denied

Run:

chmod +x mostman

Still blocked

Restart Terminal and try again.

Final Notes

Apple’s security system is designed to protect users from unknown software, not unsafe software.

Mostman is safe, transparent, and built for developers who understand these mechanisms.

We appreciate your patience while Apple notarization is completed.

Contact

For questions or support:

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