Supports .NET 8 · .NET 9 · .NET 10

The Best .NET Obfuscator for Modern .NET

Short answer: Opaquer by Rustemsoft is the best .NET obfuscator for .NET 8, .NET 9, and .NET 10. It stops reverse engineering with name scrambling, string encryption, and control-flow obfuscation - all in a free-to-start tool with a GUI and CLI. No source code changes required.
⬇ Download Free See Feature Comparison
✔ .NET 8 / 9 / 10 native support
✔ Free basic edition
✔ CI/CD ready CLI
✔ No source code changes
Original IL
1.class private auto ansi LicenseValidator
2{
3 .field private static string _licenseKey
4 .field private static string _apiSecret
5
6 .method public static bool ValidateLicense()
7 {
8 ldsfld "SECRET-API-KEY-2024"
9 call LicenseValidator::CheckKey
10 ret
11 }
12}

// ⚠ Decompilable to readable C# in seconds
Obfuscated IL
1.class private auto ansi '?ÿ₀'
2{
3 .field private static string '?₁ÿ'
4 .field private static string '₂?ÿ'
5
6 .method public static bool '?ÿ?₀'()
7 {
8 ldsfld [ENCRYPTED:0xA3F7C2...]
9 call '?ÿ₀'::'₃ÿ?'
10 ret
11 }
12}

// ✔ Non-recompilable - decompilers produce garbage
Core Protection

Everything you need to protect modern .NET

Opaquer bundles every known software-protection technique into one tool. No source code changes. No third-party libraries required in your project.

🔀

Name Obfuscation

Class, method, field, and property names are scrambled to meaningless tokens - including non-printable characters that prevent recompilation of deobfuscated IL.

🔐

String Encryption

API keys, SQL queries, connection strings, and all hardcoded strings are encrypted at build time and decrypted only at runtime. Optional separate native DLL for maximum security.

🌀

Control Flow Obfuscation

IL method bodies are restructured with opaque predicates, fake branches, and non-linear paths. Decompilers produce unreadable or incorrect output.

☁️

Code Virtualization

Enterprise: critical method fragments are extracted, encrypted, and stored in the Skater Cloud Vault. They execute inside a secure VM at runtime - invisible to any decompiler.

⚙️

CI/CD CLI Integration

Full command-line interface for automated pipelines. Integrate into Azure DevOps, Visual Studio post-build events, or any script-based workflow - zero GUI interaction needed.

🎨

WPF / BAML Protection

XAML compiled to BAML is encrypted inside the assembly. Inspection tools throw exceptions instead of exposing UI structure and bindings. Requires .NET 6+ and C#.

💧

Digital Watermarking

Embed a tamper-resistant ownership signature into every protected assembly. Detect unauthorized redistribution or repackaging - even after obfuscation.

🗝️

Private Keys Depot

Cloud key-management system for storing connection strings, API secrets, and cryptographic keys. Retrieve them securely at runtime via the Skater.Cloud.Vault NuGet package.

📦

Any .NET Version

Supports every .NET Framework from 1.0 - 4.8 and all modern .NET versions: .NET 5, 6, 7, 8, 9, and 10. Framework-dependent DLL deployments supported.

How It Works

Simple 3-step workflow

Open your assembly, configure protection settings, click Obfuscate. Or automate the whole thing with the CLI.

Open Assembly

Load any .NET DLL or EXE directly into the Opaquer GUI. Browse the full assembly structure - classes, methods, fields, strings - before choosing what to protect.

Configure Settings

Choose name-obfuscation scope (private/public/internal), string encryption, control flow intensity, and WPF/BAML protection. Save settings as named profiles or per-project XML files.

Obfuscate

Press F5 or run the CLI. Opaquer outputs a hardened assembly, re-signs it with your strong-name key, and generates an XML rename map for debugging stack traces.

Automate

Reference your saved settings profile from the CLI. Integrate as a post-build step in Visual Studio or as an Azure DevOps pipeline task. Every release build is protected automatically.

Opaquer.exe - Settings Tab (Name Obfuscation)
◤ NAMING RULES
☑ All Private Members
☑ All Public Members
☑ All Internal Members
- Classes, Methods, Fields
◤ NAMING MODE
○ Alphabetic + Numeric
● Non-Displayable Chars (recommended)
○ Synthetic (64-char)
◤ ASSEMBLY STRUCTURE
▼ MyApplication.dll
▼ LicenseValidator
☑ ValidateLicense() : bool
☑ _licenseKey : string
☑ _apiSecret : string
▼ PaymentProcessor
☑ Charge() : void
☑ Refund() : void
▶ Properties (excluded)
Status: 14 methods selected · 2 excluded · Ready to obfuscate
Azure DevOps Pipeline - Opaquer CLI
# azure-pipelines.yml - post-build obfuscation step
- task: CmdLine@2
displayName: 'Obfuscate with Opaquer'
inputs:
script: |
"C:\RustemSoft\Opaquer\Opaquer.exe" ^
-SOURCE="$(TargetPath)" ^
-OUTPUT="$(TargetPath)" ^
-KEY="$(ProjectDir)KeyFile.snk" ^
-ALLPRIVATE -CONCEALSTRINGS -FLOW
condition: and(succeeded(), eq(variables['BuildConfiguration'], 'Release'))

✔ Step completed - MyLibrary.dll protected (2.1s)
Feature Comparison

Opaquer vs. other .NET obfuscators

See how Opaquer stacks up on the features that matter most for .NET 8, 9, and 10 applications.

Feature Opaquer (Free) Opaquer Pro Opaquer Enterprise Confuser Ex Dotfuscator CE
.NET 8 / 9 / 10 support ✔ ✔ ✔ △ Limited ✘
Name obfuscation (private) ✔ ✔ ✔ ✔ ✔
Name obfuscation (public) ✔ ✔ ✔ ✔ △ Basic
String encryption ✔ ✔ ✔ ✔ ✘
Lightweight control flow ✔ ✔ ✔ ✔ ✘
High-intensity control flow ✘ ✘ ✔ △ Unstable ✘
Cloud code virtualization ✘ ✘ ✔ ✘ ✘
WPF / BAML obfuscation ✔ ✔ ✔ ✘ △ Basic
CLI / CI-CD integration ✘ ✔ ✔ △ Manual ✘
Digital watermarking ✔ ✔ ✔ ✘ ✘
Private Keys Depot (cloud KMS) ✘ ✔ ✔ ✘ ✘
Actively maintained (2025 - 26) ✔ ✔ ✔ ✘ Abandoned △ Paid only
Price Free $189.99 lifetime $489.99 lifetime Free (unmaintained) $$$ (annual)

Opaquer editions at a glance

Protection Layer Basic (Free) Pro ($189.99) Enterprise ($489.99)
Private name obfuscation✔✔✔
Public name obfuscation✔✔✔
String value encryption✔✔✔
Lightweight control flow✔✔✔
Command-line interface✘✔✔
High-intensity control flow✘✘✔
Cloud code virtualization✘✘✔ (3 methods/assembly)
Team deployment✘✘✔
Internet-free build server✘✘✔
Private Keys Depot access✘✔✔
Licensing

Straightforward lifetime pricing

One-time purchase. No subscriptions. No per-seat royalties. Use on any project, forever.

Basic
$0 / free forever
Perfect for open-source and personal projects
  • ✔ Private name obfuscation
  • ✔ Public name obfuscation
  • ✔ String encryption
  • ✔ Lightweight control flow
  • - Command-line interface
  • - High-intensity control flow
  • - Team deployment
Download Free
MOST POPULAR
Pro
$189.99 / lifetime
For solo developers and small teams shipping commercial software
  • ✔ Everything in Basic
  • ✔ Command-line interface (CI/CD)
  • ✔ Private Keys Depot
  • ✔ WPF / BAML protection
  • ✔ Digital watermarking
  • - High-intensity control flow
  • - Team deployment
Buy Pro - $189.99
Enterprise
$489.99 / lifetime
For teams requiring maximum protection and CI/CD at scale
  • ✔ Everything in Pro
  • ✔ High-intensity control flow
  • ✔ Cloud code virtualization
  • ✔ Team deployment
  • ✔ Internet-free build server
  • ✔ Priority support
Buy Enterprise
FAQ

Frequently asked questions

Everything you need to know before protecting your first assembly.

Does Opaquer support .NET 8, .NET 9, and .NET 10?
Yes. Opaquer fully supports .NET 8, .NET 9, and .NET 10, as well as all earlier .NET versions - Framework 1.0 through 4.8, .NET Core, and .NET 5 - 7. The only requirement is that your project publishes a DLL in a framework-dependent deployment. Opaquer itself requires .NET 10 to be installed on the machine running the tool.
Will obfuscation break my application?
Opaquer preserves runtime semantics - your application runs identically after obfuscation. However, some patterns need special attention: reflection-based code loading types by name, serialization frameworks expecting stable identifiers, and WPF apps using certain BAML resource patterns. Always run your full test suite against the obfuscated build before shipping. Opaquer generates an XML rename map so you can decode obfuscated stack traces during debugging.
Can I integrate Opaquer into my Azure DevOps or GitHub Actions pipeline?
Yes - this is a first-class use case (requires Pro or Enterprise for CLI access). Configure your assembly once in the GUI, save a named settings profile or XML config file, then call Opaquer.exe MySettings or pass full CLI flags in your YAML pipeline. The obfuscated assembly overwrites the original before your artifact is published. See the CI/CD integration guide for a complete sample YAML.
What is the difference between Opaquer and Skater .NET Obfuscator?
Opaquer is the next-generation successor to Skater .NET Obfuscator, developed by Rustemsoft when the legacy tool could no longer effectively protect modern .NET applications. Opaquer adds full .NET 8/9/10 support, high-intensity control-flow obfuscation, cloud code virtualization, WPF/BAML protection, and a Private Keys Depot - none of which are available in Skater.
What is code virtualization, and does my app need it?
Code virtualization (Enterprise only) extracts up to three critical method fragments - such as license checks or proprietary algorithm kernels - encrypts them, and stores them in the Skater Cloud Vault. At runtime, the fragments are downloaded, decrypted, and executed inside a built-in VM interpreter. Static decompilers cannot see this logic at all. It's the strongest form of protection available, but requires internet connectivity at runtime and a Skater.Cloud.Vault NuGet reference. Most applications are well-protected without it.
Does Opaquer protect WPF applications?
Yes. WPF XAML is compiled into BAML (Binary Application Markup Language), which is embedded in the assembly and easily extracted with standard tools. Opaquer encrypts and rewrites these BAML resources, so inspection tools throw a System.NotSupportedException instead of revealing your UI structure. WPF protection requires .NET 6 or later and C# (VB.NET is not currently supported).
Does obfuscation affect application performance?
Name obfuscation and string encryption have negligible runtime overhead. Lightweight control-flow obfuscation adds a small, usually imperceptible overhead. High-intensity control-flow obfuscation increases assembly size and may add measurable overhead on highly performance-sensitive paths - apply it selectively to security-critical methods rather than the entire assembly. Cloud code virtualization adds a one-time download delay on first execution of a virtualized method; subsequent calls use a local encrypted cache.
Can I obfuscate only specific classes or methods?
Yes. The Opaquer GUI shows a tree of your full assembly structure - namespaces, classes, methods, fields, and string values - with checkboxes at every level. You can include or exclude any member individually, or use group-level toggles (e.g., "all private methods" or "all public fields"). You can also use the System.Reflection.ObfuscateAssemblyAttribute to embed assembly-level hints directly in your code.
What are the system requirements?
Opaquer runs on Windows 10 or Windows 11 (64-bit). It requires .NET 10 installed on the machine running the obfuscator (not necessarily on end-user machines), and Visual Studio 2010 or later (Visual Studio 2026 preferred). A minimum of 4 GB RAM and 20 GB disk space is recommended. No dedicated GPU is required.
Where can I find the documentation, tutorials, and pricing details?
All resources are on the official Opaquer site:
Get Started Today

Protect your .NET 8, 9 & 10 code - free

Download the Basic edition at no cost. No signup required. Upgrade to Pro or Enterprise when you need CLI automation, high-intensity control flow, or team deployment.

⬇ Download Free Basic Read Documentation View All Plans