References — Execution Model, Scheduling & Rendering

Primary sources first. Where a secondary source is listed it is because it is unusually good, not because it is convenient.

Specifications (normative)

• WHATWG HTML Standard — §8.1.7 Event loops — task queues, "perform a microtask checkpoint", "update the rendering". The authoritative source; the update-the-rendering steps are shorter than expected and worth reading once in full.
• WHATWG HTML — Processing model — how a task queue is chosen. This is where "there is no global FIFO" is normative.
• WHATWG HTML — Queuing tasks — task sources.
• W3C Long Animation Frames API — LoAF, blockingDuration, script attribution.
• W3C Event Timing API — PerformanceEventTiming, interactionId, the 16 ms durationThreshold floor.
• WICG Scheduling APIs — scheduler.postTask, scheduler.yield, priority semantics.
• CSSOM View — offsetWidth etc. — why geometric reads force layout.

Explanatory (high quality)

• Jake Archibald, In The Loop (JSConf.Asia 2018) — still the best single explanation of tasks vs microtasks, and the origin of the listener-checkpoint example used in Step 1.
• Jake Archibald, Tasks, microtasks, queues and schedules.
• web.dev — Optimize INP
• web.dev — Optimize long tasks — the source of the "yield every ~5 ms" guidance.
• web.dev — Long animation frames API
• Chrome for Developers — Scheduler API
• Chrome for Developers — Avoid large, complex layouts and layout thrashing
• Paul Irish, What forces layout / reflow — the definitive list of layout-forcing properties.

Implementation / source

• Chromium: docs/ on the renderer main-thread scheduler; blink::scheduler::MainThreadSchedulerImpl — task queue priorities and policy transitions. Guided path in browser-framework-internals.md §16.
• React: packages/scheduler/src/forks/Scheduler.js — schedulePerformWorkUntilDeadline; why MessageChannel over microtasks and setTimeout.
• web-vitals library — src/onINP.ts is the reference implementation of interaction grouping. Read it if you intend to compute INP yourself; the grouping subtlety in docs/analysis.md is handled there.

Security-adjacent (why measurement is constrained)

• MDN — SharedArrayBuffer and cross-origin isolation
• web.dev — Why you need cross-origin isolation — COOP/COEP, Spectre, timer coarsening.

Deliberately excluded

Generic "JavaScript Event Loop Explained" posts. They are overwhelmingly derived from one another and a substantial fraction still assert the pre-2019 three-tick await behaviour, which Checkpoint 3 in docs/verification.md disproves in about four seconds.