What's inside:

Variables — batch correction of 5 .jbeam parameters across a whole folder: nodeWeight, beamDeform, beamSpring, beamDamp, beamStrength. Each one is a 0–200% dial (100% = no change), so the new value is current x percent/100. It runs recursively over every .jbeam, skips commented and non-numeric values, and makes a backup before writing.

Engine — full engine tuning: a live power/torque graph, an editable torque curve, all mainEngine parameters (idle/max/rev-limiter RPM, inertia, friction, damage thresholds), tuning stages (intake/exhaust/ECU curves) and an interactive "pit-stop" dyno.

Constructor — generates a complete, valid engine .jbeam from scratch (nodes/beams, torque curve, all parameters) with a live two-way code editor.

Code editor — a full Monaco (VS Code) editor embedded offline: file tree, tabs, search, syntax highlighting for .jbeam/.lua/.json, and image preview. Opens on its own URL at /editor.

3D viewer — a wireframe view of the nodes/beams of any .jbeam, with per-node and per-beam parameter labels.

Offline documentation (new): a complete offline copy of the official BeamNG modding documentation is built right into the app, so you can read it without internet, right next to your files. All 232 pages from documentation.beamng.com/modding are included with the same structure — navigation tree on the left, article in the center. Two languages: English is the original, Russian is a full machine translation of every page (each translated page notes that it's automatic and links to the original). Everything is embedded — text, tables, code blocks with syntax highlighting, and all 578 screenshots/diagrams/GIFs — so it all works offline. Every page has its own bookmarkable URL (e.g. /docs/vehicle/intro_jbeam/jbeamsyntax). There's also a mod template generator: a button at the bottom of the tree creates a ready starter skeleton of a car mod (folder structure, base .jbeam, engine, info.json, .pc) with comments in the chosen language.

Bilingual and offline: the whole UI switches between Russian and English with one click, and the choice is remembered. Everything — including the 12 MB Monaco editor and the 55 MB documentation — is embedded via go:embed, so the program is a single self-contained file that never needs the network.

Requirements: Go 1.21+ installed (on macOS: brew install go).

Running in development (macOS): ./build.sh — runs go run ., starts the server and opens the browser.

Building: ./build.sh win builds WidthCorrector.exe (Windows, cross-compiled from Mac); ./build.sh mac builds the macOS binary. zenity on Windows works without cgo, so the .exe builds straight from a Mac. The -H windowsgui flag removes the black console window (remove it in build.sh if you want the server log).

Address: after startup the server listens on http://127.0.0.1:8723 and opens the browser automatically. Main routes: / (app), /editor (code editor), /docs (documentation).