How to use Synergy for free

Note: This article has been updated to mention Deskflow which did not exist in 2022.

Related: Open Source and Synergy

Is Synergy Really Open Source?

You might’ve heard that Synergy is open source. That’s true, but there’s a little more to the story. Let’s break it down.

Isn’t Open Source Software Supposed to Be Free?

Not necessarily.

In the open source world, "free" usually means freedom — the freedom to view, modify, and share the source code — not always “free of cost.” That’s why you sometimes hear:

“Think free as in free speech, not free beer.”

In other words, open source software can be free to modify and redistribute, but developers and companies are still allowed to charge for the product, services, or support.

How Synergy, Deskflow, and Open Source Fit Together

• Synergy 1 is the original open source project and it's still actively maintained today. Since Synergy 1 forms the core engine of Synergy 3, it has to continue evolving to stay secure, stable, and compatible with modern systems.
• Synergy 3 is the latest version built on top of Synergy 1’s open source core. It adds a modern user interface, new features, and is easier to use. Synergy 3 is not free, but it uses the free and open source Core from Synergy 1.
• Deskflow is the upstream project where the open source core is developed. If you want to get hands-on with the code, tweak it yourself, or build it from scratch, Deskflow is where you start.

Can You Use Synergy for Free?

Yes, if you’re comfortable compiling it yourself.

The source code for Deskflow (the core engine used by Synergy 1) is free to download. To run it, you’ll need to build it manually, using a tool like CMake.

“Building” (or compiling) simply means turning human-readable code into a program your computer can run.

Building from source isn’t hard, but it does require some setup, mostly gathering the right tools and libraries, known as dependencies.

Quick Primer: What Are Dependencies?

Dependencies are the pieces of software your project relies on. Think of them as building blocks; libraries, tools, and SDKs that save developers from reinventing the wheel.

When compiling Deskflow, you'll typically need:

• An IDE (Integrated Development Environment) like Visual Studio or Xcode
• A compiler (the tool that turns code into a runnable app)
• Some libraries (shared pieces of code like networking or encryption support)
• Occasionally, an SDK (Software Development Kit) for your operating system

Your IDE usually bundles a compiler, and CMake will guide you through most of the setup.

Why Give Away the Source Code?

Because open source drives innovation.

By sharing the core code, Synergy benefits from a wider community of developers who spot bugs, suggest improvements, and even submit their own fixes. Many important improvements start as community contributions.

Deskflow acts as the living foundation and Synergy builds on it to deliver a polished, stable, multi-platform experience which has gone through QA (quality assurance) making it more suitable for non-developers.

Why Charge for Synergy 3 Then?

Developing a product like Synergy 3 — with its modern design, continuous updates, cross-platform support, and professional reliability — requires full-time effort.

There aren’t enough volunteers to keep up with everything, especially for a complex and niche application like Synergy. That’s why Synergy 3 is a paid product: to fund the engineers and resources needed to maintain and improve it.

Charging for Synergy 3 supports the future of both the upstream project (Deskflow) and the wider Synergy ecosystem.

Can Someone Just Fork Deskflow and Compete?

Technically, yes, that’s how open source works.

But what users pay for when they choose Synergy 3 is trust, professionalism, and a great experience. Over the years, Synergy has earned the loyalty of individuals, businesses, and organizations who depend on it daily. That trust is a big part of Synergy’s real value.

Want to Get Involved?

• If you want to tinker, build, or contribute, check out Deskflow on GitHub.
• If you want the polished, ready-to-go experience with ongoing support, you can purchase Synergy 3.

Thank you to everyone who’s helped Synergy grow, and a special thanks to Chris Schoeneman, who started it all back in 2001. We’re proud to continue building on the foundation you laid.

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