How to use Synergy for free

Sunday, August 7, 2022
Nick Bolton
Nick Bolton
Founder CEO & Interim-CTO of Symless (Synergy team)

Synergy is actually open source software. But what is open source software? Doesn't open source mean you don't have to pay? Well, the answer is: no, not always.

The word 'free' is often used in open source software to mean "free to modify and distribute". That's why you may have heard the phrase "free software", and there's a famous saying that goes with this: "Think free as in free speech, not free beer."

Free software is not necessarily meant to be free (as in free beer). It's meant to be freely modified and redistributed. The code for Synergy is licensed under the GNU GPLv2 (General Public License v2.0). Oh by the way, people in the know pronounce GNU as "guh-noo" (weird, eh?)

The GNU GPL covers the issue of selling free software. "You can charge people a fee to get a copy from you. The right to sell copies is part of the definition of free software."

So, there you have it. Companies can charge for open source and free software.

How to get Synergy for free

Ok, isn't this all just semantics? Probably, the reason why you're reading this blog post is because you want to get Synergy for free (as in free beer). Maybe free speech isn't the first thing that came to mind.

Well, if you don't want to pay, you need a little technical knowhow (but not much). So don't be scared, it's really not that hard.

Here are the steps you need to follow...

  1. Download the source code for Synergy (clone the repo or download the .zip).
  2. Install the required dependencies required to compile Synergy.
  3. Finally, compile Synergy to create the binary which you can run.

That's it really, three easy steps. Now you're a software developer! 😉

Hint: You don't need to use the IDE that we advise (you could use whatever IDE you like).

What does 'compile' mean?

As odd as it sounds, computers (well, CPUs, actually) don't understand the code that Synergy is written in (which is C++ by the way). Compiling is what turns code into a 'binary', which is a file containing instructions that your CPU can run (known as 'machine code').

So, it's really that simple. Compiling code is not complicated... sometimes what makes it a bit complicated are 'dependencies'.

What are dependencies?

Dependencies are what let us developers "stand on the shoulders of giants" to achieve great work much faster and easier than we could do otherwise. One type of dependency are sometimes 'libraries', which is code meant to be shared between many applications. A dependency library is usually some code that someone else has written (such as the TLS library).

Dependencies can also be the tools that you'll need in order to compile. These usually include an IDE (integrated development environment), and a compiler (oddly enough, the thing that does the actual compiling). Often, the IDE will include the compiler that you need. You'll sometimes also need something called an SDK (software development kit) which is mostly just standard libraries that are commonly used on a particular OS (operating system).

Why are you telling people this?

Doesn't Symless want keep this secret? What's in it for the business? Aren't businesses just interested in profit?

The main purpose of Symless (the company behind Synergy) is to improve Synergy and make it even better. Quite often, people who compile Synergy from source are also curious about how it works. Sometimes that curiosity leads to smart people coming up with their own bug fix. Maybe you're a smart person? Many fixes in Synergy come from people like you fixing problems for themselves. They just want to share the solution so maybe someone else can benefit... even if it's only a quick 'hack' (which is when you solve a problem quickly without much thought about the consequences). Disclaimer: I'm a bit of an expert at these, certainly not something to be proud of!

But, there's usually a catch. These fixes are often just for one OS, like Windows. But, since Synergy is supported on other platforms (such as macOS and Linux), that's where Symless comes in. We take the rough and ready fixes from volunteers and turn them into polished and well tested fixes that work on every OS.

And, what if I want to report a bug?

You can report bugs via our GitHub issue tracker. We also welcome enhancement and feature requests too. We can't promise to fix every bug, but we'll try our best!

I managed to fix a bug, what now?

Wow, well done! That's not easy. Next stop: Create a PR (pull request) and share your genius with the world. Also, want a job?

Can't you just give us the binaries?

We charge for access to our download page so that we can fund future development of Synergy. It's kind of our thing.

So, can people copy your code and put you out of business?

Many people have thought that.

Synergy has been copied and cloned in various ways over the last two decades. And, we're still here. Some simply people fork our GitHub repo, rename it to something silly, muck about with the logo and then don't really do much else. Ok, I know that sounds churlish, but I'm just having fun... I don't like to live in the past. I think forks are really cool! When they actually contribute something useful, we go ahead and implement it. And all forks aside, other companies outright copy the code and release it as proprietary software (probably... obviously it's hard to tell). We're still here though, and none of that has affected our ability to keep improving Synergy.

Over the last ten years, we've built up an incredible amount of trust with our customers who truly believe in what we're doing. They understand that to improve a product like Synergy, it takes more than well meaning people saying hopeful things. It takes money to pay hard working talented software engineers who devote full work days to improving Synergy's code. That trust translates into word of mouth, which is the main source of revenue used to improve the product. Worldwide, we have the trust of regular people and businesses alike who depend on us every day to keep making Synergy better.

People who don't understand this just don't get how branding and businesses work, and probably never will.

Ok, maybe I'll pay, but how is the money spent?

Synergy is a bit unusual. It's not like other open source software.

Because Synergy is very difficult to work on and also quite niche, there aren't many volunteers lining up to work on it for free. A massive amount of the original work was done by Chris Schoeneman over five years, between 2001 and 2006. Chris worked on Synergy out of pure passion. After Chris moved on to other projects, a number of people began working hard on fixing bugs and adding new features...

Many of them were paid, by Symless.

Our core mission at Symless is to continuously improve Synergy, and make sure it remains the most popular keyboard and mouse sharing app on Earth, ever.

Kudos, Chris. Your dream lives on.

Want to be a part of something great? Purchase Synergy today

August 7, 2022
Nick Bolton
 (revised on 

Get started with Synergy

Learn about Synergy

If you have any further questions, please contact us.