Indeed . . . as someone who works with an in-house language, I can affirm that the ratio of time we've spent on the initial parse/compile steps to the time spent on things like error reporting and optimization is probably approaching 1:100 at this point.

I find the error reporting the hardest thing. And a lot of "tips and techniques" kind of neglect that you actually may have syntax errors and need to report them to the user in a helpful way.

I think the post is pointing out that there's less magic involved in writing a compiler than one may initially think.

> writing a good compiler is somewhat more difficult

Also depends on how you define what's good.

You might want a compiler to give good CPU performance, memory, code size, debugging information, robustness, start-up speed, etc.

Some of these can be difficult - any combination is even more difficult again.