.NET SDK

Flipswitch works with .NET applications through the OpenFeature SDK and its native OFREP provider — no custom Flipswitch package needed.

GitHub: open-feature/dotnet-sdk · open-feature/dotnet-sdk-contrib

This integration uses the OpenFeature Remote Evaluation Protocol (OFREP), which evaluates flags via polling. Real-time SSE streaming is available in official Flipswitch SDKs.

Requirements

.NET 8.0+
OpenFeature SDK

Installation

dotnet add package OpenFeature.Providers.Ofrep

Quick Start

using OpenFeature;
using OpenFeature.Contrib.Providers.Ofrep;

var provider = new OFREPProvider(new OFREPProviderOptions
{
    BaseUrl = "https://api.flipswitch.io",
    Headers = new Dictionary<string, string>
    {
        ["X-API-Key"] = "YOUR_API_KEY"
    }
});

await Api.Instance.SetProviderAsync(provider);
var client = Api.Instance.GetClient();

var darkMode = await client.GetBooleanValueAsync("dark-mode", false);

Evaluation Context

Pass user attributes for targeting:

var context = EvaluationContext.Builder()
    .SetTargetingKey("user-123")
    .Set("email", "user@example.com")
    .Set("plan", "premium")
    .Set("country", "SE")
    .Build();

var showFeature = await client.GetBooleanValueAsync("new-feature", false, context);

Detailed Evaluation

Get full evaluation details including variant and reason:

var details = await client.GetBooleanDetailsAsync("feature-flag", false, context);

Console.WriteLine($"Value: {details.Value}");
Console.WriteLine($"Variant: {details.Variant}");
Console.WriteLine($"Reason: {details.Reason}");

ASP.NET Core Integration

var builder = WebApplication.CreateBuilder(args);

var provider = new OFREPProvider(new OFREPProviderOptions
{
    BaseUrl = "https://api.flipswitch.io",
    Headers = new Dictionary<string, string>
    {
        ["X-API-Key"] = builder.Configuration["Flipswitch:ApiKey"]!
    }
});

await Api.Instance.SetProviderAsync(provider);

var app = builder.Build();

app.MapGet("/feature", async (HttpContext http) =>
{
    var client = Api.Instance.GetClient();
    var context = EvaluationContext.Builder()
        .SetTargetingKey(http.User.FindFirst("sub")?.Value ?? "anonymous")
        .Build();

    var enabled = await client.GetBooleanValueAsync("new-feature", false, context);
    return Results.Ok(new { feature_enabled = enabled });
});

app.Run();

Direct OFREP API

You can also call the OFREP endpoints directly via HTTP — see the OFREP protocol reference for details.