The Apollo 11 Source Code is on GitHub and It's a Time Capsule for Developers

If you've ever wondered what it took to land humans on the moon, look no further than your terminal. The original Apollo 11 Guidance Computer (AGC) source code isn't locked away in a museum archive—it's on GitHub, and it's a fascinating piece of developer history that's completely open to explore.

This isn't a re-imagining or a modern recreation. It's a transcription of the actual assembly code that ran on the hardware aboard the command module (Columbia) and the lunar module (Eagle) in 1969. For developers, it's a unique opportunity to read the code that literally took humanity to another world.

What It Is

The repository contains the source code for the AGC assembly language, often referred to as "Comanche" for the command module and "Luminary" for the lunar module. These are the raw source files that were scanned from the original printed listings and meticulously transcribed by a community of enthusiasts and experts. It’s the real deal.

Why It's Incredibly Cool

The cool factor here is off the charts, and it’s not just because it’s about space. For developers, it’s a masterclass in problem-solving under extreme constraints.

• Incredible Constraints: The AGC had a whopping 64 KB of memory and ran at a blistering 0.043 MHz. The entire system had to be fault-tolerant and real-time, handling everything from navigation to engine control without crashing. Reading the code shows you the kind of optimization and ingenuity required when every byte and every cycle counts.
• Human-Readable Comments: The code is filled with detailed comments, some serious and some wonderfully human. You’ll find explanations of complex guidance equations right next to poetic phrases and inside jokes from the MIT team that wrote it. It’s a reminder that even the most critical code was written by people.
• A Living History Project: This isn't a static dump. The GitHub repo is active, with recent commits showing ongoing efforts to fix transcription errors and improve documentation. It’s a community-preserved artifact, which is pretty much the most GitHub thing ever.

How to Dive In

You don't need to install anything to start exploring. This is a read-and-learn experience.

1. Head over to the repository: github.com/chrislgarry/Apollo-11
2. Click into the Comanche055 (Command Module) or Luminary099 (Lunar Module) directories.
3. Start browsing the .agc files. The comments are often the best part.

For a deeper dive, you can clone the repo and browse it locally:

git clone https://github.com/chrislgarry/Apollo-11.git

Final Thoughts

Browsing this code is less about running it and more about appreciating the craft. It’s a humbling reminder of what can be built with a clear goal, deep expertise, and meticulous attention to detail—even with what we’d now consider laughably limited hardware.

For modern developers, it’s a historical reference, an inspiration, and a fun rabbit hole to fall into. Next time you’re complaining about your container taking a few extra milliseconds to spin up, remember this code helped land on the moon. Check it out.

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