Databases and runtimes,
taught from the bytes up.
Eight modules that open the box. Not summaries of how a database behaves, but what happens inside a 16KB page when a row no longer fits, and why that determines the shape of every schema you write. Each one ends with you building a working version of the thing.
Modules
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Every chapter ends with something you run against a real server. You check the claim yourself rather than trusting the page.
Motion where motion is the point
Diagrams animate when the movement carries the explanation: a page splitting, an LRU list shuffling, a replica applying a log.
Byte level where it matters
Page headers, row formats and wire protocols appear as the actual bytes, with the offsets, not as labelled rectangles.
You build one
Each module closes with a capstone: a storage engine, a SQL interpreter, an ORM, a runtime. Knowing and having built differ.