Captain's Modlist — Auto-Update Setup

Set this up once and the pack updates itself. After that you just hit Launch — it pulls the latest mods and configs automatically. No reinstalling when a new version drops.

Minecraft: 1.21.1  ·  Mod loader: NeoForge 21.1.230  ·  Recommended RAM: 6–8 GB

The Pack URL (you'll need this in step 4)

https://files.boreal-mulley.ts.net/captains-modlist/pack.toml
On the same network/LAN as the server? Use the local URL instead — it's faster and needs no Tailscale:
http://192.168.0.101:8087/captains-modlist/pack.toml
Already have a Captain's Modlist instance? (An older version, or one you set up by hand.) You don't need a fresh instance — skip to Converting an existing instance.

1. Install Prism Launcher

Download from prismlauncher.org/download and install:

  1. Windows: grab the Windows installer (.exe). If it complains about missing files, install the MSVC redistributable linked on that page.
  2. macOS: download the .dmg, drag Prism to Applications.
  3. Linux: Flatpak (flatpak install flathub org.prismlauncher.PrismLauncher) or your distro's package.

On first run, accept the defaults and let it auto-detect Java (it bundles one).

2. Add your Minecraft account

Accounts (top-right) → Manage Accounts → Add Microsoft → sign in with the account that owns Minecraft: Java Edition.

3. Create the instance

  1. Add Instance (top-left) → Custom tab.
  2. Name it Captain's Modlist.
  3. Minecraft version: 1.21.1.
  4. Click Mod Loader → NeoForge, version 21.1.230.
  5. Click OK.

Then give it memory: right-click the instance → Edit → Settings → Java → tick Maximum memory allocation → set 6144–8192 MB.

4. Connect the auto-updating pack (packwiz)

  1. Download packwiz-installer-bootstrap.jar from the packwiz releases page (the single .jar asset).
  2. Right-click the instance → Edit → Open Folder. Open the minecraft subfolder and drop packwiz-installer-bootstrap.jar inside it.
  3. Back in Edit → Settings → Custom commands, tick Custom commands and set the Pre-launch command to: 
    "$INST_JAVA" -jar packwiz-installer-bootstrap.jar -g -s client https://files.boreal-mulley.ts.net/captains-modlist/pack.toml
    LAN players: swap in the http://192.168.0.101:8087/... URL.

That's it — the -s client flag installs the client-side mod set.

5. First launch

Hit Launch. The first run downloads everything (~2 GB of mods + resourcepacks, straight from CurseForge/Modrinth) — this can take several minutes. When it finishes it boots straight into the game.

6. Updating later

Just launch the instance. The pre-launch step checks the pack every time and downloads only what changed. You never reinstall.

Converting an existing instance

If you already have a Captain's Modlist instance in Prism, do this instead of steps 1–5 to switch it over to auto-updating. (Use this only for a Captain's Modlist instance — pointing the updater at a different pack would mix the two together.)

  1. Check the version. Right-click the instance → Edit → Version. It must be Minecraft 1.21.1 with NeoForge 21.1.230. If it's anything else, set NeoForge to 21.1.230 there — or just make a fresh instance using steps 1–3 above (cleaner).
  2. Back up first. Right-click the instance → Copy instance (or copy its minecraft/mods, config, and kubejs folders somewhere safe). The updater overwrites config/ and kubejs/ and reconciles mods/, so keep a safety copy.
  3. Clear out the old mods. Edit → Open Folder → open minecraft/mods/ and delete everything inside it. The updater redownloads the exact current set; leftover old-version jars are the #1 cause of crashes after converting.
  4. Add the updater jar. Drop packwiz-installer-bootstrap.jar into the minecraft/ folder (download it from the packwiz releases page if you don't have it).
  5. Set the Pre-launch command. Edit → Settings → Custom commands, tick Custom commands, and paste the same command from step 4 above: 
    "$INST_JAVA" -jar packwiz-installer-bootstrap.jar -g -s client https://files.boreal-mulley.ts.net/captains-modlist/pack.toml
  6. Launch. It downloads the current pack and reconciles your instance — you're now auto-updating. From here on, just launch (see Updating later above).

Troubleshooting

  1. "Failed to download" / hangs at pre-launch: open the Pack URL in a browser to confirm it loads. If the public files.boreal-mulley.ts.net URL fails, use the LAN URL or ask Captain.
  2. Crash on first load after an update: a mod may have just updated — launch again (the updater sometimes needs a second pass), or report it.
  3. Want to keep a personal mod? Don't put it in mods/ — the updater removes untracked files there. Ask Captain about an unmanaged folder.
Heads up: config/ and kubejs/ are overwritten on every update (the host controls pack config). Your keybinds and video settings are safe — the pack uses the Default Options mod and does not sync your options.txt.