Tests are validation-first programs. Unlike the examples, they are written to assert edge cases, error propagation, cancellation behavior, backpressure, and module integration boundaries. They should fail when a regression is introduced.

The tests are deliberately local and synthetic. They verify that x.async composes cleanly with selected V modules without modifying those modules and without depending on public network services, fixed ports, filesystem paths, or fragile server shutdown behavior.

Current subfolders:

net_http/: in-memory net.http request/response work through Pool.
net_websocket/: in-memory websocket.Message processing and callback-style error propagation through Task and Group.
mcp/: in-memory MCP JSON-RPC request/response dispatch through Task.
veb/: in-memory veb.Context response lifecycle through with_timeout().

Run through the guarded validation path:

sh vlib/x/async/tools/validate.sh

The validation script uses isolated VTMP and VCACHE and runs serially.