Faultsense/faultsense-agent

Faultsense skips the usual E2E setup entirely by putting the assertion next to the element it checks, so it travels with your app instead of living in a separate test suite that rots. Running against live traffic rather than synthetic test runs means it catches the weird real world interactions that scripted tests never think to simulate. At under 18KB with support for React, Vue, Svelte and Rails Turbo, it is aimed at teams who want continuous production confidence without maintaining a parallel testing codebase. Still a two star repo, but the concept of inline, environment agnostic assertions is a fresh angle on an old problem.