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WTFPL is harmful to software developers

Occasionally, I run into a piece of software that utilizes an inappropriate license with a crude title. Today I want to talk about one of those licenses. It is called the WTFPL and it is harmful to any software developer that uses it.

I don't use foul language even among impolite company, so I'm not going to copy the license text here. You can read it if you want but it isn't necessary. There are about 300,000 words in the English language at any given time. Of those, about 200 words are considered to be rude, crude, foul, and generally inappropriate to use in most settings. The words a person chooses to use in casual conversation says a lot about them.

Language issues aside, the basic gist of the WTFPL license says that you can do whatever you want with the software that the license is associated with. If you look at a traditional software license (aka EULA) with its many pages of text and the various "license wars" out there, the idea behind the WTFPL begins to sound fairly wonderful. The software developer who chooses the WTFPL picks it because it sounds cool and are tired of software licenses, but they have completely missed the primary purpose of a software license in the first place: Protection against spurious lawsuits. The WTFPL does NOT protect the software developer. In fact, it does the exact opposite and spells out, in no uncertain terms, that the person using the software (even just downloading it constitutes use) can do whatever they want to the author of the software.

Let's look at a legitimate example of how that could play out: If I download a piece of software that uses the WTFPL license and then have a heart attack, I or my insurance provider can sue the author of that software for damages to cover the cost of the hospital visit and whatever my medical needs are later on. That's at least $100,000 (USD) right there out of pocket. And I'll most likely win. Even the most flimsy causality association is all that has to take place and I win. Showing causality is as easy as: I downloaded your software and shortly afterward I had a heart attack. Your software didn't prevent it from happening.

Now you might say, "Wait, hold on. That can't possibly be how it works." Sorry. That's how it works. A fully uppercase paragraph like the following is seen in most license agreements that pass legal muster:

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Broadly, that's legalese for "You agree to not sue me for use of this software". Without a clearly defined paragraph like that, you, as a software developer, open yourself up to ugly (and really stupid) lawsuits that are easily defended against by simply using a suitable software license. Also, unless you are extremely confident that you understand what you are doing, you should never alter a vetted license except to fill in blanks (e.g. your name and the current year) nor should you use an unvetted license.

The WTFPL is, of course, missing that crucial paragraph and is an unvetted license. However, the WTFPL is actually much worse than that. The wording of the WTFPL really invites people to sue the software developer. I recall reading about a case years ago where one party in a lawsuit put a friendly "Welcome to our admin interface" type of message on their login screen. Sounds great! However, they ended up trying to prosecute someone who illicitly gained access to their systems and actually lost the case because of the login screen's welcome message, which is what made it newsworthy. "Welcome"/"Do whatever you want" style messaging seems nice but is a legal minefield not worth walking into. The WTFPL can easily be read as I just described. The lesson to learn here is to not invite/welcome people to do things to you that you don't want them to actually do. Instead, take your time and select a suitable software license that properly protects you from harmful, damaging lawsuits.

If you were considering the WTFPL or have already used it, I understand the sentiment that you may not like software licenses and just want to flaunt it. Courts of law aren't impressed by that though. I highly recommend using the MIT license instead of WTFPL or another unvetted "public" license that hasn't gone through multiple layers of legal analysis (e.g. "The Unlicense" or even my own). The MIT license has everything you need to protect you from a legal perspective, it is short, it is the most permissive popular software license out there that I've found, it has been vetted by real lawyers, and it is Open Source Initiative (OSI) approved. You can use it with confidence and avoid embarrassing legal situations. Don't take on legal risks that you don't need to take.

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