Just-in-time (JIT) compilation is a technique used by interpreters to compile code on-the-fly, just before executing it, rather than compiling the entire program ahead of time like a traditional compiler. It's a way to get the best of both worlds - the flexibility of interpreted code with the performance of compiled code, kind of like having your cake and eating it too (if the cake was made of bytecode).

How to use it in a sentence

• I was trying to optimize my code, but then I remembered that the JIT compiler will probably do a better job than me anyway, so I went back to browsing Hacker News.

• The startup's new interpreter uses just-in-time compilation to make their trendy language almost as fast as C, which is great news for the dozens of developers using it.

If you actually want to learn more...

• JIT Compilation Techniques - This article dives into the nitty-gritty details of how JIT compilers work their magic, for those times when you really want to procrastinate on that feature you're supposed to be building.

• The Java HotSpot Performance Engine Architecture - A classic paper on the HotSpot JIT compiler used in Java, which is responsible for making Java's performance almost tolerable.

• Intro to JIT Compilers - A gentler introduction to just-in-time compilation that won't make your eyes glaze over quite as quickly as the other links.

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