Five ways to register your license.

The B5SecurityKit license key unlocks unrestricted access to all B5 packages. Register it once in your top-level host project. The key is white-space insensitive, so it can be broken across multiple lines.

a appsettings.json — ASP.NET Core

The easiest way for ASP.NET Core apps — add the b5secure:license setting:

{
  "b5secure": {
    "license": "{your-trial-key}"
  }
}

b Web.config / App.config — .NET Framework

For .NET Framework apps still on the migration path, add it to <appSettings/>:

<appSettings>
  <add key="b5secure:license" value="{your-trial-key}" />
</appSettings>

c Environment variable

When running multiple B5 apps, register once via B5SECURE_LICENSE (restart your host to pick it up):

# macOS / Linux
export B5SECURE_LICENSE="{your-trial-key}"

# Windows (PowerShell)
setx B5SECURE_LICENSE "{your-trial-key}"

d In code, before startup

Call B5License.Register() before the Never Trust pipeline is built — e.g. in Program.cs:

using B5SecurityKit;

var builder = WebApplication.CreateBuilder(args);
B5License.Register(builder.Configuration["b5secure:license"]);

builder.Services.AddB5Secure();   // Never Trust pipeline (B1-B5)
var app = builder.Build();
app.UseB5Secure();
app.Run();

e External license file

Keep the key out of source — register it from a plain-text file at the content root:

// B5SECURE.LICENSE.txt set to "Copy if newer"
B5License.RegisterFromFile("B5SECURE.LICENSE.txt");

Registration follows the standard .NET library licensing pattern. Exact setting and method names ship in the License Management docs.