Network I/O should be modelled as an algebraic effect (e.g., <Http> or <Net>) with operations like get, post, etc. Functions performing network access declare effects(<Http>). Handlers provide the implementation — real HTTP in production, mocks in tests.

This fits naturally with Vera's algebraic effect system and makes network I/O explicit and testable. Almost all practical programs need network access; this should be a first-class part of the standard library (Chapter 9).

Spec reference: spec/00-introduction.md § 0.8 "Network Access as an Effect"