Deploy anytime.
Release when you're ready.

A hosted dashboard for Microsoft FeatureManagement. Keep your IFeatureManager, FeatureGate, and feature tag helper code, change flags without redeploying, and skip the Azure subscription.

dotnet add package Acmi.FeatureFlags.Client

Start Free Read the Quick Start (5 minutes)

ASP.NET Core on .NET 10 or later

Why Developers Choose FeatureFlags.app

Built for Microsoft's Feature Management libraries

IFeatureManager, IFeatureManagerSnapshot, [FeatureGate], and the <feature> tag helper work as they always have.

// Program.cs
builder.AddFeatureFlags();

// controllers and views: unchanged
[FeatureGate("NewCheckout")]
public IActionResult Checkout() => View();

<feature name="NewCheckout">
    <a href="/checkout">Check out</a>
</feature>

0 network calls

per flag check

Flags are evaluated inside your app from an in-memory copy that refreshes in the background, and your app keeps using the last-known-good copy during an outage.

No Azure subscription required

Your app can run anywhere. FeatureFlags.app is a hosted service, so there is nothing to run besides the client package.

AzureAWSGCPYour servers

15 min default

Release without redeploying

Changes reach your apps within your refresh interval, which you can shorten to 1 minute.

Your users' data stays in your app

User identities and evaluation results are never sent to FeatureFlags.app. The client only downloads your flag definitions.

Gradual rollouts, targeting, and schedules

Flags use Microsoft's built-in Targeting and TimeWindow filters, so there is no new evaluation model to learn.

Percentage rolloutsUsers and groupsExclusionsTime windows

Unlimited environments, apps, and users

Pricing is by flag count only, and every plan can export flags to standard Microsoft FeatureManagement JSON.

Stop Redeploying Just to Toggle Features

Modern teams shouldn't redeploy applications just to:

Disable broken features

Turn it off in the dashboard, not the pipeline.

Release gradually

Start with a few users and raise the percentage.

Test production safely

Turn a feature on for specific users or groups first.

From a Redeploy to a Dashboard

Your flag-checking code doesn't change. Only where the flags come from does.

Before

appsettings.json

{
  "FeatureManagement": {
    "NewCheckout": true
  }
}

Changing a flag means editing the file and redeploying.

After

Program.cs

using Acmi.FeatureFlags.Client;

var builder = WebApplication.CreateBuilder(args);
builder.AddFeatureFlags();

appsettings.json

{
  "FeatureFlags": {
    "ApiBaseEndpoint": "https://featureflags.app/api/",
    "ApiKey": "[from user secrets or environment variables]"
  }
}

Change a flag in the dashboard and your apps pick it up within their refresh interval (15 minutes by default, configurable).

How It Works

1
Configure
Create feature flags and API keys through the web UI.
2
Integrate
Add the client library to your ASP.NET Core applications (.NET 10 or later).
3
Control
Toggle features on and off, or create more complex rules.

Feature Comparison

Checked against each vendor's public pricing and documentation.

	FeatureFlags.app	LaunchDarkly	Azure App Config	ConfigCat
Works with Microsoft FeatureManagement	✓	✕	✓	✕
Percentage rollouts	✓	✓	✓	✓
User targeting	✓	✓	✓	✓
Audit logs	✓	Enterprise plan	✓	✓
Price for 100 flags	$10/month (Team)	Flags are unlimited; priced per service connection ($10/month each after the first 5, billed annually), plus client-side MAU charges	Flags are not metered. About $3.65/month for a Developer store ($0.12/day, 3,000 requests/day included, no SLA), or about $36/month for Standard ($1.20/day)	$110/month (Pro)
Environments included	Unlimited	3 on the free plan; unlimited on paid	One store per environment, or labels	2 on the free plan; 3 on Pro
Apps / service connections included	Unlimited	5 on the free plan; $10/month each after that, billed annually	No app limit; request quotas apply	2 products on the free plan; 3 on Pro
Azure subscription required	✕	✕	✓	✕
Export flags as Microsoft FeatureManagement JSON	✓	✕	✓	✕
Self-hostable	✕	✕ Self-hosted Relay Proxy only	✕	✓ Proxy and private-cloud plan

Last verified: October 20, 2026, against each vendor's public pricing and documentation. Plans and prices change, so check the vendor before you decide.

Built For Modern .NET Teams

Development teams

Seeking a simple, no-frills feature flag solution.

Teams already using Microsoft FeatureManagement

That want to change flags without editing config files and redeploying.

Teams without Azure

That don't want to adopt an Azure subscription just to manage flags.

What if it goes away?

A hosted service should be easy to leave.

MIT-licensed client

See it on GitHub.

Microsoft's standard format

Flags load in plain Microsoft FeatureManagement.

Export on every plan

Export any environment to standard JSON, even while you are over your flag limit.

Public status page

Service health is on the status page.

Featured On

GitHub NuGet

Ready to Get Started?

Check out the Quick Start Guide to add it to your ASP.NET Core application.