Constant MAX_REQUEST_BODY 

pub const MAX_REQUEST_BODY: usize = _; // 2_097_152usize

The largest request body this server will hold in memory.

Two mebibytes, which is what axum bounds a buffering extractor to when nothing says otherwise. It is written down here rather than inherited silently, because it is the only thing standing between an anonymous caller and this process’s memory, and a bound that arrives from a dependency’s default is one nothing in this repository would notice changing.

It is not a bound on a blob: com.atproto.repo.uploadBlob takes the body as a stream and never buffers it, and its size limit is the blob store’s own. This is the bound on the JSON every other procedure sends.

Enforcement is streaming rather than after the fact — the body is refused as it arrives, at the first frame that carries the request past the bound, so a caller announcing or sending a gigabyte never has a gigabyte of it resident here.