What are Meld's system requirements?

Meld's runtime requirements are Python 3.6, GTK+ 3.22, GLib 2.36, PyGObject 3.36, GtkSourceView 4.0, and pycairo. These are the versions listed on meldmerge.org for running the tool. If you plan to build Meld from source rather than install a packaged build, the site points you to the current README file for the additional development and build requirements.

Runtime requirements at a glance

The site lists pycairo as a requirement without specifying a version number, so treat the others as the concrete version floors and pycairo as a required dependency.

What this means per platform

Linux/Unix

Meld is packaged for most Linux/Unix distributions and is also available on Flathub. Installing through your distribution's package manager or Flathub is the path most likely to resolve the GTK/PyGObject/GtkSourceView dependencies for you, since those are system libraries rather than Python packages you'd normally install by hand.

Windows

Windows users should download the installer. The site notes that Meld does not yet support automatic updates or portable installs, so plan on a normal installed copy rather than a portable one.

macOS

Meld is not yet supported on macOS, though semi-official builds are available. You can install from Homebrew, MacPorts, or Fink. Older third-party binaries are also still available but may have issues with recent versions of macOS. Because macOS support is described as not yet official, expect the dependency situation there to be less predictable than on Linux.

Development and build requirements

If you're compiling Meld yourself, the runtime list above is not the whole story. The site directs you to the current README file for development and build requirements. That's the authoritative place to check before attempting a source build, since build-time dependencies can differ from what's needed just to run a released version.

Practical notes

• The most recent stable release is described as the best option for most users, and changes to stable releases are kept to a minimum. If you just want Meld working, start from a stable release rather than a source build.
• You can run Meld directly from a git clone without installing it:

  $ git clone https://gitlab.gnome.org/GNOME/meld.git
  $ bin/meld
  

  This is useful for testing, but it still relies on the runtime dependencies being present on your system.
• All development happens on GNOME's GitLab instance. If a dependency problem blocks you, opening an issue there or asking on the discussion board is the route the project itself points to.

The short version: check that Python 3.6, GTK+ 3.22, GLib 2.36, PyGObject 3.36, GtkSourceView 4.0, and pycairo are available, prefer a packaged or Flathub install on Linux, use the installer on Windows, and consult the README before building from source.