Supported Features

  • Editing functions in monobehaviours, normal classes or static classes

    • You can edit the body of the function in any way that is valid C#. We recompile the whole function, so it works the same as you’re already used to.
  • Editing lambda methods

    • If you modify a lambda, we hot-reload the existing lambda. So for example, store a lambda in a static field during startup, and then edit the lambda without running startup code, your change to the lambda will still apply immediately.
  • Editing lambda methods with closures

    • If you use an outside variable inside your lambda, your lambda will work as usual. If you use a new outside variable, then your lambda will be hot-reloaded only when you create it again. for example the lambda in Array.Sort(() => …) is recreated every time you run the code, so it will always work as expected.
  • Editing async/await methods

  • Editing properties (get/set)

  • Editing events (add/remove)

  • Editing indexers (square bracket access such as dictionaries)

  • Editing operators methods (explicit and implicit operators)

  • Editing conversion operators methods such as == and +=

  • Adding/Editing/Removing constructors of classes

  • Adding/Editing/Removing local functions

  • Changing a method from async to sync, or from sync to async

  • Deleting any methods, properties, fields, class

  • Adding/editing/removing using directives. E.g. Using UnityEngine

  • Adding/Editing variable initializers. E.g. private int x = 1 in a class

    • E.g. int myField = 10. Do note that variables are only initialized when you create a new class instance. We don’t re-run variable initializers for already instantiated classes, as it could break existing code.
  • Use of newer C# syntax. Switch expressions, using statements, pattern matching, null coalescing statements, etc. By default, we support all syntax supported by the C# compiler.

  • Adding/removing attributes. Note that your code will compile, but System.Reflection won’t pick up on the attribute changes.

  • Use of nullable anywhere

  • Adding new methods

  • Adding, editing, deleting parameters in methods

  • Changing the return type of any method. Includes instance, static, properties, events, indexers, generics, etc.

  • Changing accessibility, E.g. changing a method from private to public

  • Static keyword changes, eg making a method static

  • Renaming methods

  • Editing generic methods just like normal methods

  • Adding/editing/deleting generic parameters

  • Adding/editing/deleting the constraint clause of a generic method (E.g. where T : class, new())

  • Adding/replacing/deleting ref, out, in modifiers on arguments

  • Editing code marked with [BurstCompile]

  • Attaching a debugger to modified code in the Unity Editor, including burst compiled code

  • Attaching a debugger to a Unity Player (On-Device). Supports all code edits just like in the Unity Editor

  • Partial coroutine support - changes do apply to newly created coroutines, but ongoing ones won't update yet

Features on the Roadmap

If you’re using or considering a Business license, and one of these is very important to you, let us know and we’ll prioritize it.

  • Adding, editing, removing fields
  • Adding new classes/structs
  • Adding, editing, removing constructors of structs
  • Adding/editing enums
  • Editing generic class methods
  • Editing variable initializers in partial types
  • Editing a method with return type dynamic, or one of the arguments using dynamic
  • Editing a method body with anonymous types
  • Adding or removing one of the following method keywords: partial, abstract, virtual, override, extern
  • Deleting the constructor of a class doesn't remove the constructor logic. As a workaround, consider leaving an empty constructor instead of deleting it, and maybe delete the constructor on the next full recompile.
  • Async method that are already executing are not patched - only new invocations will use the updated logic
  • Supporting editing code dynamically generated by libraries like Unity Multiplayer hl-api, Photon, Bolt, Mirror
  • Adding C# files
  • Applying changes to ongoing coroutines

Always Requires a Full Recompile

  • Adding, modifying, deleting .asmdef files. Note that scripts inside assembly definitions are supported as you’d expect, only modifications to the .asmdef file itself require a full recompile
  • Modifying define symbols, or other things in .csproj or .sln files

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