I drove 12,000 miles on an open-source FSD alternative.

What I drive

My car is a 2020 Tesla Model Y equipped with AI3 hardware. The device on the windshield is a comma four, and the software in that clip is sunnypilot, a community fork of @comma_ai's open-source openpilot. So far my setup has covered over 12,000 miles, 897 drives, and 310 hours of drive time.

In comma's own words, openpilot is adaptive cruise control plus lane centering, and it needs an alert driver. Instead of nagging you to tug the wheel, it uses a camera to check that I'm watching the road. I'm still the one driving. NHTSA's guidance for this whole category, Level 2, is four words long: You Drive, You Monitor.

Why I went this way

Honestly, it started with subscription fatigue. I already pay monthly for a pile of software. When I installed my comma four in February, the newest FSD versions were built for Tesla's newer AI4 (HW4) hardware … Even now, Tesla's newest FSD build for AI3 is a lighter version it calls v14 Lite, distilled from the v14 that AI4 cars run. That's what pushed me to look for an alternative.

… comma does have an optional subscription called comma prime. It … adds cellular connectivity, keeps drive videos accessible for a year instead of the three days included free, and gives you up to an extra year of warranty if you subscribe within 30 days of getting your device. I don't pay for it.

That comparison is why I use the phrase FSD alternative, and it's the same phrase X's Today's News used in its headline about my clip.

I mean it as a cost and convenience comparison, not a claim about capability or safety. They're different products from different companies taking different approaches, and I'm not ranking them.

The other reason is that the code is open. openpilot has been public since @realGeorgeHotz and comma open-sourced it in 2016, so nearly 10 years, and comma says cars with its devices have driven over 400 million miles. I can read the code my car runs, see what changed between releases, and follow the people building it. comma's docs list 335 supported cars, so this isn't really a Tesla thing. My Model Y just happens to be the car it's in.

What the clip shows

The clip is one of my drives with sunnypilot running on the comma four. It's the same setup behind those 12,000+ miles, and driver monitoring, which comma requires forks to keep, is stock and untouched.

The modification question

Some people saw the clip and called this a mod. That's a fair thing to raise, so here's the straight answer.

sunnypilot is a fork, and comma doesn't certify it. comma does publish rules for forks, and the one that matters most is simple: don't disable or weaken driver monitoring. comma backs that up in writing: forks that don't follow its safety rules can get their developers and users banned from comma's servers.

comma also says a fork that changes the safety code, the part that limits what the software can make the car do, has to keep comma's full safety test suite passing. That safety code runs on a separate chip inside the comma device, but a fork ships its own version of it, and sunnypilot does. It modifies the safety code for a feature called MADS, which keeps lane keeping active in more situations. It runs comma's safety tests in its public code checks and says it follows comma's safety rules as closely as possible, though comma doesn't verify that.

What I can speak for is my own setup. I haven't touched driver monitoring, so it watches me the way it was designed to.

Who's responsible

The responsibility is mine. comma's terms say you use it at your own risk, and I take that literally. When it's engaged, I'm still the driver, and it's my job to catch what it misses. Anyone who installs one of these should go in with that understanding.

If you found me through the viral clip and you're interested in a setup like this, feel free to ask me more, look through my past posts, and read comma's docs. And if the part about staying responsible doesn't sit right with you, this probably isn't the setup for you, which is fine.

Where I land

I use open-source software as an FSD alternative because it costs me less, gives me more room to customize it, and lets me see how it works. It's driver assistance. I watch the road while the car helps with speed and lane keeping, and every mile is still my responsibility.

A big part of why I've stuck with this is the comma community of developers. The people building openpilot and the forks like sunnypilot, and sharing their work in the open, have taught me most of what I know about this setup.

I'll keep posting what I learn, including the boring parts and the parts that don't work. If you have questions about the setup, ask. I'd rather give you the real answer than the clip version.