Features

Every feature.

Built for hundreds of mods, several playthroughs and friends on the same pack.

Finds your game
On every store and launcher, or in a folder you pick.
Steam GOG Epic Games EA app Lutris Xbox app
Installs the mod loader
And keeps it up to date.
BepInExMelonLoader + 9
Every mod site
8 sites, searched at once.
Nexus Mods CurseForge GitHub Thunderstore Vintage Story Mod DB Paradox Mods itch.io Patreon
Free
No account, no ads, open source.
AGPL-3.0$0

Download for Windows or Linux. 333 games supported.

A profile for every playthrough

Each has its own mods, settings and launch options.

  • Install any version, and roll back
  • Read the changelog before you update
  • Freeze a profile on its versions
A mod's detail panel in Mortar with its version, update channel and Keep this version

Stardew Valley on SMAPI

SMAPI installed and kept current, and hundreds of mods with cover art.

  • Nexus Mod Manager Download lands in the right profile
  • Nexus collections with their FOMOD choices
Mortar showing a Stardew Valley profile of mods with cover art

BepInEx games

Lethal Company, Valheim and more, with packages kept in the profile, not the game folder.

  • Import r2modman or Gale profiles
  • Failed or duplicate plugins show in Problems
  • Dedicated server profiles
A Lethal Company profile in Mortar with its Thunderstore mods

Every mod site in one search

Every site the game uses, searched at once. Dependencies come along.

  • Mods you already have are marked
  • Every download comes from the mod's own page
The Browse tab listing Lethal Company packages from Thunderstore

Know what broke before you launch

Missing dependencies, outdated versions and conflicts, in plain words.

  • One-click fixes
  • After a crash, the mod at fault is named
The Problems tab explaining which mod wins each content conflict

See what slows your startup

Time to the title screen and what each mod costs.

  • Compared with the last launch
  • Console and logs inside Mortar
The Performance tab with time to title screen and each mod's startup cost

Play from Steam Deck Game Mode

Add a profile to Steam and play it from Game Mode.

  • Full gamepad control
  • Laid out for the Deck's screen
Game select at the Steam Deck’s resolution with the Lethal Company row focused by a gamepad

Your profiles on all your PCs

Pair two computers with a short code. Profiles arrive with their mod files.

  • No account
  • Nearby computers are found for you
The Pair a computer dialog showing a one-time pairing code

Scanned before it installs

Each mod goes past your antivirus first: Windows' scanner, ClamAV or your own command.

General settings with the antivirus choices: Automatic, clamd socket, custom command or off

Companions

Works with your browser and your game.

Two optional, open source add-ons, installed from inside Mortar.

Browser extension

Marks Nexus Mods, Thunderstore and other mod sites with what your profile has, and sends downloads to Mortar. Firefox and Chromium browsers.

About the extension Source

Game bridge

A small mod in each profile. It runs console commands and times startup in Stardew Valley, and reports which plugins loaded in BepInEx games.

SMAPI bridge BepInEx bridge