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2026-05-15 | 🗺️ Word Meter Slice Nine — Plan Refinement 🪓

🧭 Why The Plan Needed Refining

🎯 The Word Meter PureScript port has shipped eight slices in a row, and every one of those slices fit comfortably inside a single pull request. 🪜 The port’s guiding rule is that every slice must deliver end-to-end, user-visible behavior in the smallest coherent shape, and that horizontal layers like capabilities or foreign-import modules are never their own slices. 🧱 The next item on the slice table read simply as on-device pre-flight plus cloud fallback, and at first glance that sounded like one slice. 🪓 A closer look at the legacy JavaScript bundle, however, revealed three distinct features hiding inside that one heading, and shipping all three at once would have produced a pull request large enough to be difficult to review with care. 🧪 So before any PureScript code changes, the responsible next step was to refine the plan itself.

🪞 What The Legacy Bundle Actually Does

📜 Reading the legacy word-meter.js from top to bottom, the recognition layer turns out to have three almost-independent jobs. 🪪 The first job is wiring up a real SpeechRecognition instance — choosing between the standard window.SpeechRecognition constructor and the prefixed webkit variant, setting continuous mode and interim results, picking the locale, attaching three event handlers, calling start, and re-arming the recognizer with a brief delay after each automatic stop. 🛰️ The second job, layered on top, is asking the static SpeechRecognition.available and SpeechRecognition.install methods whether the device has a local language pack and silently kicking off a download if it can. 🪂 The third job is the small but critical safety net: when an on-device recognizer ignores the pre-flight result and rejects start at runtime with a language-not-supported error, the meter tears it down and tries the cloud path one more time, never showing the user that anything went wrong.

🪓 Three Features Become Three Slices

🪜 Each of those three jobs is independently user-visible, and that is the project’s working definition of a slice. 🎯 Slice nine-a is going to wire up a real SpeechRecognition instance using only the cloud path — no processLocally hint, no static-API pre-flight, no fallback orchestration. 🎤 When that slice lands, the meter will count real speech in any browser that already exposes the Web Speech API, which is the single largest behavior change the port can make. 🛰️ Slice nine-b will then teach the orchestrator to prefer the on-device language pack when the static API is present, falling through to the cloud path transparently whenever the pre-flight says the pack is unavailable, the download fails, or the static API is missing altogether. 🪂 Slice nine-c will close the small but real gap where a successful pre-flight is followed by a runtime rejection from start, by retrying on the cloud path exactly once per counting session and recording the whole story in the diagnostics drawer. 🧭 After those three slices, the original slice ten — pointing the published tool at the PureScript bundle and retiring the legacy build — becomes safe to take on.

🧬 The Pure Dedup Logic Belongs With Nine-A

🤝 One detail worth calling out is that the Android Chrome cumulative-transcript bug from issue six-eight-nine-seven needs to be handled the moment any real SpeechRecognition instance is in play. 🪞 Continuous mode with interim results on that browser emits each refinement of a single utterance as a fresh finalized result that contains the cumulative transcript so far, and a naïve index-based deduplication would over-count dramatically. 🧮 The refined plan therefore folds that dedup logic into slice nine-a as a new pure module called WordMeter.Recognition.Delta, with a typed classification that maps the previous and incoming transcript pair into one of four named outcomes: ignore the duplicate, extend the existing utterance with a word delta, ignore an earlier snapshot of the same utterance, or start a new utterance. 🪪 That keeps the correctness fix inseparable from the slice that introduces real transcripts, which is the right relationship.

🪪 The Capability Pattern Holds

🧰 The port has already proven the capability pattern works at scale: clock, clipboard, environment snapshot, DOM mount, session state, storage, and wake lock each live behind a typeclass with a production AppM instance and at least one deterministic test newtype. 🪨 Slice nine-a will introduce one more capability, called Recognition, with the same shape. 🪞 Its AppM instance will own the lifetime of the currently active recognizer through a new field on the application environment, exactly parallel to the wake-lock sentinel reference that slice seven introduced. 🧪 Its test newtype, RecordingRecognitionM, will capture every start and stop call as a value in a list so the reducer wiring is unit-testable without ever touching the browser. 🔇 The thin foreign-import shim will follow the same never-silently-swallow-errors rule the rest of the foreign code obeys, surfacing every synchronous throw and every promise rejection through a typed error continuation rather than a Boolean or a default value.

🪜 What This Pull Request Contains

📝 This pull request contains exactly two changes. 📋 The first is a refinement of the slice table inside the Word Meter PureScript port specification, replacing the single pending row for slice nine with three pending rows for slices nine-a, nine-b, and nine-c. 🪡 The second is a new narrative section in the same specification that describes the scope, the new modules, and the user-visible difference of each sub-slice in enough detail for a future session to pick up cleanly without re-deriving the decomposition. 🧊 No PureScript code is touched, no tests are added, and no behavior changes for users yet. 🧱 The point of this pull request is to make the next three pull requests easier to land safely, one user-visible slice at a time.

🪞 The Underlying Principle

🪨 It is tempting to read a slice heading literally and then ship whatever code happens to satisfy the heading. 🧭 The discipline that makes this port pleasant to work on is the opposite: every slice has to be the smallest end-to-end feature that genuinely changes what the user can see or do. 🪜 When a slice heading silently contains more than one such feature, the right move is to refine the heading before writing any code, because the alternative — a huge pull request with three loosely coupled features — is much harder to review, much harder to roll back, and much harder to teach the next contributor about. 🪪 This pull request is a small but real instance of that principle in practice.

📚 Book Recommendations

📖 Similar

• The Pragmatic Programmer by Andrew Hunt and David Thomas is relevant because it argues at length for incremental delivery, ruthless decomposition, and the idea that the smallest thing that could possibly work is almost always the right next move.
• Working Effectively with Legacy Code by Michael Feathers is relevant because it teaches the art of carving a real codebase into manageable seams before adding new behavior, which is exactly what this plan refinement is doing to the legacy recognition layer.

↔️ Contrasting

• Worse Is Better by Richard Gabriel offers the opposite worldview, one in which shipping a slightly wrong thing today is preferable to shipping a beautifully decomposed thing tomorrow, and reading it is a useful corrective whenever the urge to over-plan threatens to slow real progress.

🔗 Related

• Domain-Driven Design by Eric Evans is relevant because the typed sub-features that slice nine-a introduces — recognizer lifetime, the typed transcript-integration outcome, the typed recognition error code from slice eight — are textbook ubiquitous-language modeling at the boundary between a messy browser API and a clean reducer.