Revise the epic's direction from a minimal Janet shim to ripping Janet
out entirely — Chez becomes the sole substrate. The missing spine: the
compiler pipeline itself only runs on Janet today (the analyzer executes
on the Janet host; the IR->Scheme emitter is host/chez/emit.janet). Phase
3 is re-scoped to self-host the compiler on Chez (emitter -> Clojure
jolt.backend-scheme, reader -> jolt-core, compile-from-source bootstrap
fixpoint). Phase 5 becomes a hard delete of both src/jolt/*.janet and
host/chez/*.janet. Sequencing: core parity first, then self-host, then
delete.
host.* replaces janet.* as the portable interop namespace (each host implements
it over its own FFI). Add a :native dep form so projects declare needed shared
libs (libcurl/openssl/zlib) — not git-fetchable, but surfaced to the user and
probed at load so a missing .so yields a precise error, not a raw dlopen fail.
Account for jolt's layered interop surface on Chez — the janet.* bridge, the
FFI-backed java.* shim libs (http-client TLS/gzip, router, db), jpm-module Janet
deps (spork/http) — with ../examples as the end-to-end acceptance gate. New
epic child jolt-cf1q.7, gated behind Phase 2.
Phased plan for re-hosting jolt's substrate on Chez Scheme, organized around two
north stars: minimal host shim (push everything possible into self-hosted
jolt-core, drop the tree-walking interpreter) and the spec/conformance corpus as
the host-neutral correctness contract. Closes obsolete Janet-backend/cgen beads
superseded by the native substrate.