It requires a lot of skill to write TeX, but the key is declaring it feature frozen for almost 40 years. I like Knuth's approach to open source: "Here is the co

It requires a lot of skill to write TeX, but the key is declaring it feature frozen for almost 40 years. I like Knuth's approach to open source: "Here is the code, I wrote it because I needed it, I hope you find it useful. Now, if you don't mind I have things to do. I no longer use email but I read snail mail every six months"