Hey everyone,                                                    

 I've been working on an open-source project called Slopsmith - a self-contained Docker web app for browsing, playing, and practicing Rocksmith 2014 CDLC directly in your browser. No  Rocksmith installation needed to use it.
                                                                                                                                                                                           
 What it does:                                                                                                                                                                             
   
 - Note Highway Player - a canvas-based highway renderer with all techniques (bends, slides, harmonics, palm mutes, tapping, chords with brackets, sustain tails, synced lyrics, etc.)     
 - 3D Highway - an alternative Three.js 3D perspective view closer to the real Rocksmith experience
 - Library Browser - grid view with album art and a hierarchical artist/album/song tree view with letter filter. Server-side search and pagination
 - Practice Tools - A-B looping with saved loop sections, 4-count click-in at song tempo, rewind animation, speed control (0.25x to 1.5x)
 - Fretboard View - live fretboard overlay showing active notes in real-time                                                                                                               
 - Tab View - traditional scrolling guitar tablature via alphaTab
 - Section Map - color-coded minimap of song structure (intro/verse/chorus/solo) with clickable navigation                                                                                 
 - Favorites & Edit Metadata - favorite songs, edit title/artist/album/art
 - Retune to E Standard - pitch-shift songs in Eb/D/C#/C Standard to E Standard with one click                                                                                             
 - Setlist Builder - create ordered playlists with sequential playback                                                                                                                     
 - Practice Journal - auto-tracks your practice time, speed, loops used. Dashboard with 30-day chart and most-practiced songs
 - Metronome - audible click and visual beat flash synced to the song's tempo                                                                                                              
 - Tone Player - view the amp/pedal/cabinet signal chain with actual Rocksmith gear artwork
 - MIDI Amp Control - auto-switch presets on your real amp/modeler (Helix, Kemper, GP-5, etc.) when song tones change during playback                                                      
 - CDLC Editor/Creator - a DAW-like visual arrangement editor. Load an existing CDLC or import a Guitar Pro file, see notes on a timeline with audio waveform, drag and drop to move  notes, add/delete notes, set techniques, save back to PSARC. Full undo/redo.                                                                                                              
 - Import Tab - drag and drop GP3/GP4/GP5 files to create CDLC with MIDI audio with 1 click.
 - RS1 & Base Game Extractor - extract songs from RS1 compatibility packs and the base game's songs.psarc into individual playable CDLCs                                                   
 - Profile Import - import play counts, favorites, and scores from your Rocksmith profile
                                                                                                                                                                                           
 How it works:                                                    
                                                                                                                                                                                           
 Everything runs in Docker. Point it at your DLC folder, and it scans and caches metadata using parallel in-memory PSARC reading (no temp files).
                                                                                                                                                                                           
 The app has a plugin system - all the features above are modular plugins. You can install only what you want. Anyone can build new plugins.

 Tech:

 - Python/FastAPI backend with SQLite                                                                                                                                                      
 - Canvas 2D + Three.js frontend
 - Custom PSARC reader with AES-CFB-128 decryption                                                                                                                                         
 - SNG-to-XML conversion via Rocksmith2014.NET                    
 - Supports both custom CDLC and official DLC (auto-converts SNG to XML)
                                                                                                                                                                                           
 Links:
                                                                                                                                                                                           
 - Core app: https://github.com/byrongamatos/slopsmith            
 - All plugins listed in the README

 It's free, open-source (MIT), and self-hosted. Runs on any machine with Docker - desktop, NAS, server.                                                                                    
   
 Would love to hear your feedback and feature suggestions. If you build a plugin, let me know and I'll add it to the directory - we already have a community-contributed MIDI Capo plugin!
      

Here's what's happened since the first post:                     

Slopsmith Desktop - For those who found Docker intimidating, there's now a standalone desktop app. No Docker, no terminal - just download and run. It includes everything from the web version plus a native audio engine built with JUCE:                                                    

VST3/AU/LV2 plugin hosting - load your amp sims, pedals, and effects directly

Neural Amp Modeler (NAM) - load .nam capture files for amp modeling with GPU-accelerated inference

Cabinet IR loading - load your own impulse responses

Automatic tone switching - the signal chain changes as tones change during a song, matching what the CDLC author intended

Real-time pitch detection for tuning and note feedback

https://github.com/byrongamatos/slopsmith-desktop

NAM Tone Engine plugin - The same amp modeling is now available in the web version too, as an installable plugin running entirely in your browser via WebAssembly. Plug your guitar into any USB interface, load a .nam model and cabinet IR, and play through it with no external software. Tone auto-switching and guitar stem ducking (mutes the guitar stem in sloppak songs so you play "for real" in the mix) work the same way. This started as a https://github.com/byrongamatos/slopsmith/issues/8 - i built it after the original author didn't follow up.      
 
Community contributions since launch:

topkoa - sloppak open format with multi-stem support, splitscreen plugin, sloppak converter + stems mixer, vocals SNG decoder for official DLC lyrics, highway API extensions

jweibel22 - left-handed mode, ARM architecture fix

masc0t - MIDI capo, invert highway, "Find More CDLC" search plugin

renanboni - Jumping Tab (Yousician-style horizontal tab view)

asktoby - Windows 11 install tutorial  

 Other new features:
  
Multiplayer - join a room with friends, play together with synced highways. Shared song queue with voting. Optional recording + built-in mini DAW mixer for post-session mixdowns Lyrics Sync - paste plain text lyrics + a sloppak song with vocals stem, and Whisper AI generates a time-synced .lrc file

6-stem separation - Demucs now splits into guitar, bass, drums, vocals, piano, and other (via remote GPU server)

Plugin update checker - Settings now shows available updates for installed plugins with one-click update                                                                                
30+ plugins in the directory and growing   

 The plugin system is the part I'm most proud of - anyone can build a plugin with just a plugin.json, an HTML file, and some JS. No build tools, no framework, no dependencies. Seven community plugins already exist from people i've never met.                                                                                                                               

 https://github.com/byrongamatos/slopsmith | https://www.youtube.com/watch?v=f_XTS9tVeaU | https://github.com/byrongamatos/slopsmith-desktop  

so cool! Downloading - now! anyone know if this works with the Quad Cortex as an audio device?

It does

Hey there,

Just tried to give it ago and while it sees my rocksmith cable I dont get any output from it at all. Im probably doing something wrong Im guessing, so if you have any hints id appreciate it. Overall it looks quite impressive.

So a little more digging. Input is registered as note detection settings shows it but its not coming through the speakers at all. So to be clear, music plays fine, instrument is not being played through the speakers (im on the desktop version 0.27)

you need to set up your own tones using vst/nam/ir . I think someone is preparing a video on this

Trying to get this installed on Linux mint 22.3, any advice as none of the .sh files seem to do anything

6 hours ago, p00ki3 said:

Hey there,

Just tried to give it ago and while it sees my rocksmith cable I dont get any output from it at all. Im probably doing something wrong Im guessing, so if you have any hints id appreciate it. Overall it looks quite impressive.

So a little more digging. Input is registered as note detection settings shows it but its not coming through the speakers at all. So to be clear, music plays fine, instrument is not being played through the speakers (im on the desktop version 0.27)

Had the exact same issue until I unchecked this box. Plugins > Audio.

How secure is this?

I'm using macOS and my spidey sense goes off when Terminal is involved since I'm not very familiar with it.

In the Github, the install instructions involve having libraries installed. Also, I think I heard about some security flaw with docker, so its great that there is an alternative. I just want to make sure its legit and more importantly secure.

I'm hoping it is because slopsmith looks like a great Rocksmith replacement from the videos I've seen.

Hi, there is a desktop build under the releases of slopsmith-desktop repo also for macOS . The project is 100% open source there is nothing fishy going on, lots of people have looked through the code

4 hours ago, RadNukaKitty said:

Trying to get this installed on Linux mint 22.3, any advice as none of the .sh files seem to do anything

There is an AppImage build in the slopsmith-desktop repository

How do you run this on an intel mac? I don't see any .dmg files? Do i have to run command line prompts to achieve this?

20 hours ago, xasiklas said:

It does

I cannot seem to get it to work with an AxeFX III as the audio device. Any advice?

I’m Sorry there are no x86 builds yet

On 5/15/2026 at 10:20 AM, ConmanCometh said:

Had the exact same issue until I unchecked this box. Plugins > Audio.

Thank you ! this fixed it for me

17 hours ago, WolfeMac said:

I cannot seem to get it to work with an AxeFX III as the audio device. Any advice?

It works with my FM9, but detection is janky. We need to be able to select the input channel. Right now the app only lets you select channel 1 and 2, but AxeFX uses inputs 5 and 6 for the DI.

1 hour ago, bodolza said:

It works with my FM9, but detection is janky. We need to be able to select the input channel. Right now the app only lets you select channel 1 and 2, but AxeFX uses inputs 5 and 6 for the DI.

I think I figured it out. I was looking for audio setting is the obvious place.. "Settings"

But I found them in Plugins....

10 hours ago, bodolza said:

It works with my FM9, but detection is janky. We need to be able to select the input channel. Right now the app only lets you select channel 1 and 2, but AxeFX uses inputs 5 and 6 for the DI.

Detection is indeed janky, but its being actively worked on. We started at 2% now its closer to 60% and still improving.

There is an open issue for showing all input channels.

hey, so In the future, or right now, will there be an option to add piano and keyboard parts to the songs to play along with? I'm a little sad theres no option to add sheet music to my sleep token songs and be able to play it with the keyboard highway.

Amazing work. I think it will improve a lot in a few months.

Thank you very much xasiclas, byrongamatos and all the community

22 hours ago, pawrlight22 said:

hey, so In the future, or right now, will there be an option to add piano and keyboard parts to the songs to play along with? I'm a little sad theres no option to add sheet music to my sleep token songs and be able to play it with the keyboard highway.

This is already possible. Open the editor, open a psarc, click add keys, and play with your midi keyboard to record the arrangement. Then save. It's still barebones, but it gets the basic job done, it will improved based on the community's suggestions

What an amazing tool, thanks a lot for this. My laptop runs RS2014 really badly. Slopsmith runs great.

Only downside is the audio sync of tabviewer, it totally off the track.

I am a Mac user and I installed Slopsmith install went well, even dug up a steam cd version of rocksmith2014 and created my dlc folder to show up on my favorites tab easy. I download the mp whatever files and dragged them into that folder, I liked the folder to the directory in the game and got the songs to show up. I tried converting the files within slopconvert once I scanned for songs and I can't get it to work. where can I find libraries even just the basic rocksmith 2014 ones or even all dlcs? why dont my Cdlcs work. it says no playable arrangements found in psark even though there is

On 5/15/2026 at 6:35 PM, divebomber said:

How secure is this?

I'm using macOS and my spidey sense goes off when Terminal is involved since I'm not very familiar with it.

In the Github, the install instructions involve having libraries installed. Also, I think I heard about some security flaw with docker, so its great that there is an alternative. I just want to make sure its legit and more importantly secure.

I'm hoping it is because slopsmith looks like a great Rocksmith replacement from the videos I've seen.

did you have any luck with this. I'm looking at this too and I'm in MacOS. I'm useless at GIT HUB, and not exactly what to do

4 hours ago, jasmith85 said:

did you have any luck with this. I'm looking at this too and I'm in MacOS. I'm useless at GIT HUB, and not exactly what to do

go to https://github.com/byrongamatos/slopsmith-desktop/releases/tag/v0.2.8 scroll all the way down where it says assets, download the dmg file for macos and run it. That's it

4 hours ago, jasmith85 said:

did you have any luck with this. I'm looking at this too and I'm in MacOS. I'm useless at GIT HUB, and not exactly what to do

I did the desktop app that @xasiklas sent the link for. No issues installing and its working on my Macbook Air M2 running macOS Tahoe. The only issue I'm having is figuring out how to use slopsmith. I was able to link my Rocksmith DLC folder and downloaded some tones so that I can get sound but that about all I've had time for. I've watch some youtube videos but again haven't had time to figure out all of the settings in the program.