Build log: the TS/JS Lens

July 18, 2026 · Milestone M9 Lens scope

The JavaScript/TypeScript adapter now emits concept annotations while it owns the syntax tree. Each annotation includes the owning graph node, language, concept ID, exact line span, and source snippet. No UI heuristic and no model call decides that a concept exists.

The first JS/TS concept set covers async/await, arrow functions, destructuring, optional chaining, nullish coalescing, import/export module syntax, TypeScript annotations, interfaces, generics, and JSX. The deterministic Lens translates only those IDs into teaching copy and adds the real file:line citation in the Study module.

Graph schema 4 makes the annotation language explicit. The star chart keys rows by language plus concept, so Python and TypeScript async/await evidence cannot merge accidentally. The same distinction flows through encountered, studied, and check-derived understood counts.

Error recovery stays conservative: a broken module receives no module-level Lens claims, while a valid sibling function may keep annotations proven inside its own error-free tree. Tests compare Study notes exactly to serialized parser annotations and exercise every concept family against the mixed fixture.

M10 is next: an accessible language-focus control, real mixed-project browser QA, documentation/install updates, and the Phase 1 tester release.