AutoMapper and MediatR Transition to Commercial Licensing Under Lucky Penny Software

In a notable shift for the .NET progress community, automapper and MediatR, two widely-used libraries, have officially transitioned to a commercial licensing model under the ownership of Lucky Penny Software, effective July 2, 2025. This move introduces tiered subscription options while maintaining a free Community edition for eligible users.

New Licensing Structure for AutoMapper and MediatR

The libraries now operate under a dual-licensing system, offering both the free RPL license and a commercial license. This model is similar to those adopted by othre open-source companies like MongoDB, balancing community access with enduring development funding.

Did You No? AutoMapper has amassed over 1.1 billion downloads, showcasing its widespread adoption in the .NET ecosystem.

Tier-Based Pricing

The commercial license features a tier-based pricing structure tailored to team size, eliminating individual per-seat licenses. The tiers include:

• Standard: 1-10 developers
• Professional: 11-50 developers
• Enterprise: Unlimited developers

Subscriptions are available on a monthly or annual basis, with discounts offered for annual commitments and bundled purchases of both libraries.

Community Edition Details

A Community edition is available at no cost for:

• Companies and individuals with gross annual revenue under $5,000,000
• Non-profit organizations with annual budgets under $5,000,000
• Educational and classroom purposes
• Non-production environments

Registration for a license key is required for auditing purposes, even for the Community edition.

Accessing the Commercial Versions

The latest major versions of AutoMapper and MediatR on NuGet are released under the new dual license. Upon installation, users will be prompted to accept the license agreement and provide a license key. The license key can be configured within your services, as shown in the exmaple below:

services.AddAutoMapper(cfg => /* or AddMediatR */
    cfg.LicenseKey = "<license key here>";
});

While the libraries will function without a valid license key, messages will appear in the logs prompting users to supply one.

Pro Tip: Consider bundling AutoMapper and MediatR subscriptions for a discounted rate.

What about existing Versions?

Archived versions of the final releases of AutoMapper and MediatR remain available under their original license agreements.Existing users can continue using these versions without any required changes.

The Story Behind Lucky Penny Software

Lucky Penny Software is named in honor of the owner’s first dog, Penny. The company logo also pays tribute to her memory.