PackPulse
by Kamilchik
Server owners who ship a modpack can point PackPulse at their own manifest, so players' mods, configs and packs stay in sync at startup.
What it does
PackPulse is a Fabric and NeoForge mod that checks a server-hosted JSON manifest against the local game folder before play. It compares SHA-256 hashes of the mods, config, resourcepacks and shaderpacks folders, plus any extra top-level mod folders and an optional options.txt, then fetches only the files that are missing or changed. Files a server has removed from the manifest are deleted on the client.
The mod shows a confirmation screen before any transfer starts. It lists the files in a scrollable view, lets the player choose which ones to fetch, and waits for a button press. The default manifest URL is only a placeholder, so each server has to set its own in the client config. The environment is client-side only, so servers run without installing anything, and the code is released under the MIT License as open source. Builds exist for 1.20 – 1.21.11.
Key features
Startup sync
Missing or changed files are fetched when Minecraft starts, before the player reaches a world.
Hash-based checks
Each file is verified by its SHA-256 hash, so unchanged files are skipped and never fetched again.
Confirmation screen
Players see the file list and choose what to fetch before anything is written to disk.
Removal of old files
Files that a previous version published and that the new manifest no longer lists are deleted from the client.
Compatibility
Latest build for each game version and loader.
1.21.x12 of 12 versions with builds
1.20.x7 of 7 versions with builds
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Small communities
Server owners of small communities can keep every player's pack folders matched to the server without shipping a full launcher.
Who it’s for: Server owners who host their own modpack files over HTTPS, for example with a Let's Encrypt certificate on a domain. Each server needs its own manifest.json, which the client config points to.
How it compares
Sync Client Server (SCS) covers Fabric, Forge and NeoForge for 1.20.1 – 1.21.1 and is a client and server mod, so it must be installed on both sides. Sakura Updater is a client and server mod for Forge and NeoForge across 1.20.1 – 1.21.11, released under the GNU Lesser General Public License v3.0 only. PackPulse is client-side only, which is a different setup from both.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| PackPulse | Fabric and NeoForge | 1.20 – 1.21.11 | Client-side only | 2026-05-17 |
| Sync Client Server (SCS) | Fabric, Forge and NeoForge | 1.20.1 – 1.21.1 | Client and server | 2026-02-22 |
| Sakura Updater | Forge and NeoForge | 1.20.1 – 1.21.11 | Client and server | 2026-09-25 |
Questions
Does PackPulse need to be installed on the server?
Can a server use the default manifest URL?
What happens to a file removed from the pack?
Which loaders does PackPulse support?
In the catalog
PackPulse is one of 8,499 Technology mods on ModsFinder, and one of 4,201 Technology mods for Fabric. 19,862 mods support Minecraft 1.21.11.
More from Kamilchik
Similar mods
What the author says
PackPulseMod is an open-source client-side updater for private Minecraft modpacks. It is designed for server owners and small communities who want players to keep their pack folders in sync without shipping a full launcher.
Official listing
- Modrinth page
- modrinth.com/mod/packpulse
- Owner
- Kamilchik
- Published
- 2026-04-03
- Updated on Modrinth
- 2026-05-17
- Facts verified
- 2026-10-15