OpenBL3CMM

A visual hotfix mod editor for Borderlands 3, inspired by OpenBLCMM (Borderlands Community Mod Manager).

Made by Ty-Gone.

What is this?

OpenBL3CMM lets you create, edit, and manage BL3 hotfix mods with a visual interface — no more hand-editing giant text files. It's designed to work with OpenHotfixLoader (OHL) and B3HM.

Think of it as BLCMM, but for Borderlands 3.

Quick Start

1. Install

Download OpenBL3CMM_Setup.exe from the releases page and run the installer.

2. Set Up the Object Explorer (Optional but Recommended)

The Object Explorer lets you browse all BL3 game objects. To use it:

1. Download bl3data.sqlite3 from the repo: bl3data.sqlite3
2. Place it in: %LOCALAPPDATA%\Programs\OpenBL3CMM\datapacks\
3. Open the Object Explorer (Ctrl+E) — it auto-detects the datapack

Tip: The datapacks folder is created automatically by the installer. You can also load datapacks manually via the "Load Datapack..." button.

3. Start Modding

• Use File → New to create a blank mod, or download the Template Mod as a starting point
• Add categories and entries using the toolbar or keyboard shortcuts
• Save as .bl3hotfix or .blmod
• Place your mod file where OHL/B3HM can find it

Downloads

File	Description
OpenBL3CMM_Setup.exe	Windows installer (from Releases)
Template_Mod.blmod	Template mod file to get started
bl3data.sqlite3	BL3 Object Explorer datapack — place in %LOCALAPPDATA%\Programs\OpenBL3CMM\datapacks\

Features

Mod Editing

• Visual category tree with checkboxes to enable/disable individual entries or entire categories
• Full command display — tree shows the complete simple command (set /Game/Path/Object Property Value)
• Per-command color coding — set = blue, edit = green, clone = gold, delete = pink, etc. (customizable)
• Comment display — comments show as bright yellow labels above their entry
• Simple command syntax — write set, edit, merge, early_set instead of raw SparkPatchEntry lines
• Three entry modes — Raw Text, Simple Command (guided), or Spark Format (individual fields)
• BLCMM-style auto-format — struct values like (Key=Val,...) display with proper indentation
• Bracket matching — highlights matching ( ) pairs in the editor
• Syntax highlighting — commands, object paths, and properties colored in real-time
• Validation on save — warns about potential problems before saving
• Drag and drop reordering of entries and categories
• Copy / Cut / Paste entries and categories
• Search across all entries
• Independent windows — edit multiple entries simultaneously without overlap

Object Explorer

• Auto-load datapack — drop data.sql in the datapacks folder and it's detected automatically
• Built-in data browser — browse all BL3 game objects (Tools → Object Explorer, Ctrl+E)
• Tabbed properties — open multiple objects in separate tabs, closeable and moveable
• Clickable links — object paths in JSON become clickable, navigate with left-click or middle-click to open in new tab
• Save/bookmark objects — each tab has a clipboard of saved object paths
• Back/Forward navigation — full history with ◀ ▶ buttons, Alt+Left/Right, Mouse 4/5
• Search in properties — Ctrl+F with regex, match case, wrap around (per active tab)
• Zoom — Ctrl+Wheel, Ctrl+=/-, Ctrl+0 to reset
• Preferences menu — Keyboard Shortcuts editor accessible from menu bar
• References — browse references FROM and TO any object, double-click to navigate
• Search by path, class, or properties with "Search Properties" checkbox
• Datapack support — loads SQLite datapacks (apocalyptech's bl3refs format, Grimm's JSON data, ZIP, 7z)

Preferences

• Keyboard Shortcuts — press-to-edit capture supporting keys, mouse buttons, and scroll wheel
• Command Color Coding — customize colors per command type with color picker
• Theme selector — 6 themes: Midnight, Obsidian, BL3 Orange, Soft Dark, Soft Purple, Catppuccin Mocha
• Font & Size settings — change UI font, monospace font, and size
• Detail Panel toggle — show/hide the right-side detail panel

Tutorial

• Built-in 6-page walkthrough for new users
• Shows on first launch, accessible anytime via Help → Tutorial

DataTable Hotfixes (Type 2)

• Transparent handling — Type 2 DataTable hotfixes display as clean set TABLE ROW VALUE without showing the ugly column hash
• Column auto-recovery — the column name is preserved internally and recovered automatically on save

File Formats

• .bl3hotfix — standard OHL/B3HM text format
• .blmod — YAML-based format (requires PyYAML)
• BLIMP tags — reads and writes @title, @author, @version, @description metadata
• Disabled entries — saved as #SparkPatchEntry,... (game skips # lines)
• Import / Export — import mods as categories, export individual categories or enabled-only

Simple Commands

Command	Description	Spark Type
set	Set a property	SparkPatchEntry
edit	Level-specific set (MatchAll)	SparkLevelPatchEntry
merge	Character-loaded patch	SparkCharacterLoadedEntry
early_set	Early level patch	SparkEarlyLevelPatchEntry
news	Inject news item	InjectNewsItem
set_cmp	Compare-and-set	SparkPatchEntry
set_array	Set entire array	SparkPatchEntry
set_struct	Set struct field	SparkPatchEntry
add	Add to array	SparkPatchEntry
remove	Remove from array	SparkPatchEntry
clone	Clone an object	SparkPatchEntry
delete	Delete an object	SparkPatchEntry
create	Create a new object	SparkPatchEntry
rename	Rename an object	SparkPatchEntry
exec	Include another mod file	exec
set_mesh	Type 6 mesh placement	SparkLevelPatchEntry

Keyboard Shortcuts

Shortcut	Action
Ctrl+N	New mod
Ctrl+O	Open file
Ctrl+S	Save
Ctrl+Shift+S	Save As
Ctrl+E	Object Explorer
Insert	Edit selected entry / Add new entry
Ctrl+H	Add category
Ctrl+B / Ctrl+D	Enable / Disable selected
Ctrl+C / X / V	Copy / Cut / Paste
Delete	Delete selected
Ctrl+= / Ctrl+-	Zoom In / Out
Ctrl+0	Reset zoom

All shortcuts are customizable via Preferences → Keyboard Shortcuts.

Object Explorer

Shortcut	Action
Ctrl+F	Search in properties
Alt+Left / Right	Back / Forward
Mouse 4 / 5	Back / Forward
Ctrl+Wheel	Zoom

Installation

Pre-built Installer (Windows)

Download OpenBL3CMM_Setup.exe from the releases page and run it. The installer creates:

%LOCALAPPDATA%\Programs\OpenBL3CMM\
├── backups\       — auto-backups before each save
├── datapacks\     — place data.sql here for Object Explorer
└── mods\          — default mod directory

From Source

Requires Python 3.10+.

pip install PySide6
pip install pyyaml    # optional, for .blmod support
python main.py

Generating a Datapack

If you want to generate your own datapack instead of using the provided data.sql:

# From Grimm's extracted JSON + bl3refs
python generate_datapack.py --from-json "C:\path\to\extracted\" --merge-refs bl3refs.sqlite3 -o bl3data.sqlite3

# From 7z archive
python generate_datapack.py --from-7z "Final version.7z" --merge-refs bl3refs.sqlite3 -o bl3data.sqlite3

Get bl3refs.sqlite3 from apocalyptech's BL3 Object Refs.

Project Structure

main.py                — GUI, dialogs, tree, themes, preferences
models.py              — Data model (ModFile, Category, HotfixEntry)
parser.py              — File parser (.bl3hotfix, .blmod)
exporter.py            — File exporter
commands.py            — Simple command ↔ Spark format conversion
blimp.py               — BLIMP metadata tags
blmod.py               — .blmod YAML format
object_explorer.py     — Object Explorer window
hotfix_highlighter.py  — Syntax highlighting + validation
generate_datapack.py   — SQLite datapack generator
openbl3cmm.ico         — App icon
OpenBL3CMM.spec        — PyInstaller spec
installer.iss          — Inno Setup installer script
build.bat              — Windows build script
CHANGELOG.md           — Version history
Template_Mod.blmod     — Template mod file

Modding Resources

• BL3 Hotfix Modding Guide
• BL3 Hotfix Format
• BL3 Item and Weapon Parts
• Make Every Gun an Alien Barrel
• BL3 Mod Authors Guide
• Community Mods
• OpenHotfixLoader

Credits

• Ty-Gone — OpenBL3CMM development
• apple1417 — OpenHotfixLoader, BLIMP spec, .blmod format
• LightChaosman — Original BLCMM (inspiration)
• Apocalyptech — BL3 modding resources, Object Refs, OpenBLCMM
• BLCM Community — Borderlands modding community

License

OpenBL3CMM is licensed under the GNU General Public License v3. A copy can be found at License.txt.