Which .NET Obfuscator Supports .NET 11?

Protecting .NET 11 applications from day one

.NET 11 reached general availability on November 10, 2026, announced at .NET Conf. It is a Standard Term Support (STS) release with two years of support, so teams are now deciding whether to move production apps from .NET 10 (LTS). C# 15 is the default language version for net11.0 projects, and the runtime adds runtime-native async, which Microsoft says produces cleaner stack traces and lower overhead.

None of this changes the core reality that shipped .NET assemblies are readable. Without protection, an assembly can be decompiled to readable C# or VB.NET within seconds. Because an obfuscator rewrites compiled output, it has to be built for the runtime it protects. Opaquer was redeveloped for .NET 11 and tested extensively with several types of .NET 11 apps, so you can protect net11.0 builds from the start.

What obfuscation does to your IL

This is the “Hello World” example from the Opaquer manual: a console app with two private fields, inspected with ILDasm before and after name obfuscation.

.class private auto ansi sealed beforefieldinit Module1
{
  .field private static string str
  .field private static valuetype [mscorlib]System.DateTime today

  .method public static void Main() cil managed
  {
    .entrypoint
    IL_0001: ldsfld string ConsoleApplication1.Module1::str
    IL_0006: ldsfld valuetype [mscorlib]System.DateTime
             ConsoleApplication1.Module1::today
    IL_0015: call void [mscorlib]System.Console::WriteLine(string)
    IL_001c: ret
  }
}

.class private auto ansi sealed beforefieldinit '0AAAA'
{
  .field private static string '1AAA0'
  .field private static valuetype [mscorlib]System.DateTime '2AAAA'

  .method public static void '1AAAA'() cil managed
  {
    .entrypoint
    IL_0001: ldsfld string ConsoleApplication1.'0AAAA'::'1AAA0'
    IL_0006: ldsfld valuetype [mscorlib]System.DateTime
             ConsoleApplication1.'0AAAA'::'2AAAA'
    IL_001c: ret
  }
}

Choosing the Non-Displayable characters naming rule goes further: identifiers use characters that are invalid in IL, so the output cannot be recompiled with ILAsm.

Table 1: What a .NET 11 team needs vs. what Opaquer provides

Feature details follow the Opaquer manual and the published plan comparison; .NET 11 support comes from Rustemsoft’s own testing. Confirm current details on the pricing section.

Table 2: Threats to a .NET 11 app vs. protection technique

Obfuscation raises the cost of reverse engineering; it does not replace server-side enforcement or sound key management.

Inside Opaquer

Screenshots from the official manual. Configure once in the GUI, then save the settings for repeat runs.

Protect a net11.0 app in six steps

1. 1. Build Release. Compile your net11.0 project in Release configuration.
2. 2. Open and configure. Open the assembly in Opaquer, set naming rules, strings and control flow, and exclude members that external code references by name.
3. 3. Start light. Use Lightweight Control Flow on a small set of sensitive methods first, as the manual recommends, then expand.
4. 4. Obfuscate and inspect. Run the obfuscation, then open the output in ILSpy or dotPeek to confirm names and logic are scrambled.
5. 5. Test the protected output. Run unit and integration tests, and exercise reflection, serialization, interop and async-heavy code paths on the obfuscated build.
6. 6. Automate. Save settings to an XML file, then call the CLI from a post-build event or pipeline step. Keep an unobfuscated build for rollback.

Frequently asked questions