UEFN Verse Logs
Stream Verse logs from Unreal Editor for Fortnite directly into VS Code, with per-category and per-level filtering.
Tail the UEFN log file live, parse out the Verse-related categories, and watch your Print() output stream into a VS Code output channel — colored by log level, filtered by category, and synced with the project you have open.
Install
From the VS Code Marketplace:
code --install-extension simnjs.uefn-verse-logs
Or search UEFN Verse Logs in the Extensions sidebar (Ctrl+Shift+X).
Quick start
- Open your UEFN project folder in VS Code (the one containing
<Project>.uefnproject).
- Launch UEFN on the same project.
- The extension auto-starts the tail. Open the UEFN Verse output channel (
View > Output, pick "UEFN Verse" in the dropdown).
- Run
Print("Hello, world!") in your Verse code — it shows up live.
If autostart didn't kick in, click the Verse: stopped indicator in the status bar, or run UEFN Verse: Watch latest log from the command palette.
Features
- Auto-detect the UEFN project in your workspace via
.uefnproject (walks up parent folders from each workspace folder).
- Live tail of
%LOCALAPPDATA%\UnrealEditorFortnite\Saved\Logs\UnrealEditorFortnite.log with rotation handling.
- Filter tree in the Explorer sidebar — checkbox per category. State persists across sessions. Use VS Code's built-in log-level filter (funnel icon on the output panel) for per-level filtering.
- Quick filter picker (
UEFN Verse: Toggle filters…) — fast multi-select for power users.
- "Print() only" preset — one click, only
LogVerse lines remain.
- Restart command to reset stats and re-detect the project without leaving the keyboard.
- Status bar with live error and warning counts, click to reveal output.
- LogOutputChannel with native level coloring (Debug / Info / Warning / Error).
- Polling-based (not
fs.watch) — reliable on Windows where UEFN keeps the .log file open in shared-read.
Filters
Open the UEFN Verse view in the Explorer sidebar. Each entry from uefnVerseLogs.categories appears as a checkbox you can toggle at runtime:
| Category |
Default |
What it carries |
LogVerse |
on |
Print() output from your Verse code |
VerseBuild |
on |
Compile errors, hot reload events |
VerseProfile |
on |
Profiling output |
VerseTest |
on |
Test framework output |
LogVerseInterop |
off |
VNI module loading (chatty at startup) |
LogVerseMessageServer |
off |
Verse message server lifecycle |
LogVersePredicts |
off |
Prediction context registration (chatty) |
LogVerseUObjectGenerator |
off |
Generated UObject events |
For per-level filtering, use the VS Code log channel's own controls: the funnel icon at the top of the UEFN Verse output panel (Filter Output by Log Level for show/hide, Set Log Level for the threshold). UEFN levels are mapped to VS Code levels as Fatal/Error → Error, Warning → Warning, Display/Log → Info, Verbose/VeryVerbose → Debug.
Adding custom categories
UEFN has hundreds of log categories — anything that shows up in the Output Log filter inside UEFN can be added here. Examples: Cmd, LogValkyrieBeacon, LogFortMatchmakingV2. Settings:
{
"uefnVerseLogs.categories": [
"LogVerse",
"VerseBuild",
"LogValkyrieBeacon",
"Cmd"
]
}
Save the file — the filter tree updates live.
Commands
All keybindings use a Ctrl+Alt+V chord (Cmd+Alt+V on macOS) followed by a second key. They're rebindable in Preferences: Open Keyboard Shortcuts.
| Command |
Keybinding |
Description |
UEFN Verse: Watch latest log |
Ctrl+Alt+V Ctrl+W |
Start tailing UnrealEditorFortnite.log. |
UEFN Verse: Start watching log… |
— |
Pick any .log file in the UEFN logs folder. |
UEFN Verse: Restart tail |
Ctrl+Alt+V Ctrl+R |
Stop and re-start the tail on the same log. Resets stats and re-detects the project. |
UEFN Verse: Stop watching |
Ctrl+Alt+V Ctrl+S |
Stop the tail. |
UEFN Verse: Toggle filters… |
Ctrl+Alt+V Ctrl+F |
Multi-select picker for categories. |
UEFN Verse: Show Print() output only |
Ctrl+Alt+V Ctrl+P |
Preset: keep only LogVerse. |
UEFN Verse: Reset filters |
— |
Restore default checkbox state. |
UEFN Verse: Clear output |
Ctrl+Alt+V Ctrl+L |
Empty the output channel. |
UEFN Verse: Open output panel |
Ctrl+Alt+V Ctrl+O |
Reveal the UEFN Verse output. |
UEFN Verse: Open settings |
— |
Jump to the extension's settings UI. |
All commands are also available as toolbar buttons in the UEFN Verse view title.
Settings
| Setting |
Default |
Description |
uefnVerseLogs.autoStart |
true |
Auto-start the tail when a workspace with a .uefnproject opens. |
uefnVerseLogs.logDirectory |
"" (= %LOCALAPPDATA%\UnrealEditorFortnite\Saved\Logs) |
Override the directory containing .log files. |
uefnVerseLogs.logFileName |
UnrealEditorFortnite.log |
Active log file name in that directory. |
uefnVerseLogs.categories |
6 Verse categories |
Categories displayed in the filter tree. |
uefnVerseLogs.pollIntervalMs |
500 |
Poll interval in ms. Minimum 100. |
uefnVerseLogs.showTimestamp |
true |
Prefix each emitted line with the UEFN timestamp. |
uefnVerseLogs.showCategory |
true |
Prefix each emitted line with the log category. |
uefnVerseLogs.showProjectHeader |
true |
Print the detected project at the top of the output. |
uefnVerseLogs.revealOnError |
false |
Reveal the output panel automatically when an Error/Fatal line is emitted. |
Per-project overrides go in .vscode/settings.json.
How it works
UEFN writes every log entry — including Verse Print() output — to a single file: %LOCALAPPDATA%\UnrealEditorFortnite\Saved\Logs\UnrealEditorFortnite.log.
The extension:
- Detects the UEFN project in your workspace by walking up the workspace folders to find a
.uefnproject.
- Polls
stat() on the log file every 500 ms (configurable), reads new bytes since the previous position, reassembles partial lines across reads.
- Parses each line with a regex matching the Unreal log format
[timestamp][frame]Category: [Level: ]message.
- Filters by category prefix and by level using your TreeView checkboxes.
- Emits matching lines to a
LogOutputChannel, dispatched to debug/info/warn/error based on the parsed level.
Polling rather than fs.watch because UEFN keeps the log file open in shared-read mode while running, which makes fs.watch miss size changes until UEFN closes the file.
Limitations
- The UEFN log is global — it contains entries from every running UEFN instance. In practice UEFN runs one project at a time, so the output is effectively per-project.
- Only Windows is supported for autostart (UEFN runs on Windows only). The code path itself is platform-agnostic; on macOS / Linux you'd point
logDirectory at whatever you have.
Development
git clone https://github.com/simnjs/uefn-verse-logs.git
cd uefn-verse-logs
npm install
npm run compile
Open the folder in VS Code, press F5. A debug Extension Development Host opens. From there, open a UEFN workspace to test against a live .log.
To package a .vsix:
npx @vscode/vsce package
Contributing
Issues and pull requests welcome at https://github.com/simnjs/uefn-verse-logs.
Useful starting points:
- Bug reports — include the offending line from
UnrealEditorFortnite.log (raw, not from the output channel).
- New category — open an issue with the category name and an example line. The default list errs on the side of "useful for
Print() debugging".
License
MIT
