2N Lightning Reload | Edit C# In Play Mode Without Compiling

Stop losing your game state to a recompile.

A normal C# recompile wipes out the runtime state you were working with: the player's position, the scene setup, the exact bug you spent ten minutes reproducing. 2N Lightning Reload patches the running methods instead. You save the file and the game keeps playing with your new code.

It works on the device too. The same edit goes straight into a running Android build or a standalone player over your local network. No rebuild, no reinstall.

Nothing to sign up for. No account, no license server, no compiler service to download. It compiles with the Roslyn that already ships inside your Unity install, so it works offline and behind a corporate firewall. Import the package, press Play, done.

WHAT YOU CAN CHANGE WHILE PLAYING

Brand-new classes, structs, enums and interfaces, even in a new .cs file you write mid-session.

Coroutines that are already running, and new Unity messages (Update, OnTriggerEnter and the rest) on types that did not have them before.

New MonoBehaviours, added to live objects with AddComponent.

Unity Entities systems, SystemBase and ISystem alike, and Burst-compiled jobs.

Method bodies: logic, values, loops, LINQ, lambdas, local functions, constructors, properties, generics.

async/await, iterators, and exception filters (catch ... when).

New methods, new fields, changed signatures, removed members.

Code around a network RPC reloads too, and the call still goes over the network. With Netcode for GameObjects, the optional IL post-processor weave can reload the RPC body itself.

YOUR DEBUGGER STAYS ATTACHED

Keep Visual Studio attached while you reload. Breakpoints you set after a reload hit, in the method you edited and in the ones around it.

BUILT FOR REAL SESSIONS

Undo / redo across reloads. Step your code back and forth without retyping anything.

A status window that shows what was patched, how long it took, and why something was refused.

[OnLightningReload] callbacks and a small public API, so you can hook it into your own tools.

Settings live in ProjectSettings, so updating the package never resets them.

A typical reload lands well under a second. Reload time scales with the assembly you edited, not with the size of the whole project.

TRY IT IN 30 SECONDS

Open Tools > 2N Lightning Reload > Status Window. Drop Samples/LightningReloadDemo.cs on any GameObject and press Play. Change a number in that script and save. The running scene updates without leaving Play mode.

REQUIREMENTS

Windows editor. Unity 2021.3 to 6.5. Mono scripting backend. On-device: Android (ARMv7 development builds) and standalone players on your local network. IL2CPP and iOS are not supported; live patching needs the Mono scripting backend.

A few changes still need a Play restart. When that happens the Console tells you which one and why. The full list is in the README.