memory spy by b0rk (Julia Evans): visualise how C how variables are represented in memory
Posted by jpluimers on 2026/08/06
It is universal for most other programming languages too as explained in [Wayback/Archive] New playground: memory spy
why is it useful to look at C?
You might be wondering – I don’t write C! Why should I care how C programs represent variables in memory?In this playground I’m mostly interested in showing people how integers and floats are represented. And low-level languages generally all represent integers and floats in the same way – a 32-bit unsigned int is going to be the same in C, C++, Rust, Go, Swift, etc. The exact name of the type is different, but the representation is the same.In higher-level languages like Python it’s a little different, but under the hood afloatin Python contains a Cdouble, so the C representation is still pretty relevant.
Via
- [Wayback/A] Julia Evans on Twitter: “We built a new playground called Memory Spy where you can spy on a program’s memory! It’s at memory-
spy.wizardzines.com. I made this with @omarieclaire, and there’s a blog post about how and why we built it here https://t.co/M44K6odiii. Here’s a gif: …” - [Wayback/Archive] Julia Evans: “We built a new playground call…” – Mastodon
–jeroen
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