Sibling: Rebuilding Clojure from behavior — the method-shaped initiative asking which of Clojure's own abstractions survived its own churn (survival inward). This essay is the diffusion-outward half; its F7 argues the two are one property at two scales.

Placeholder. The question: separate Clojure the language (its adoption curve, hiring pool, library tail) from Clojure the ideas — immutable-by-default data, the REPL as the unit of work, data-as-interface (EDN/Transit), spec-style runtime contracts, managed identity/state — and ask which of the ideas the wider industry absorbed regardless of whether it wrote any Clojure. To be written.

• Frame against endurance, not advocacy: what outlived the hype, and what the ecosystem quietly adopted without the parentheses.
• Live 2026 data points from the Clojure/Conj program (ClojureDart in production, jank on LLVM, Clara Rules in mortgage underwriting since 2021) — evidence the ideas ship even where the runtime is unusual.
• Candidate spine: one durable idea per section, each with a where-it-shows-up outside Clojure and a where-it-failed-to-travel.

• Clojure/Conj 2026 — Brendan Foote's What tipped the scales for Clojure, jank, and Clara Rules in Applied Logic Programming.