# Development log — Privacy: Period Tracker

```
Status: Current
Owner: _null
Last reviewed: 2026-08-18
Governs: the dated record of what happened
Review trigger: Nothing. This file is appended to, never revised.
```

## How to use this

Newest first. **One entry per work session**, written before you stop — that is
step 6 of `docs/WORK_CYCLE.md`, and the two lines it insists on are `Next
action` and `Blockers`.

Those two are not decoration. The next session starts by reading the top of this
file, and a session that ended without saying what came next hands the one after
it a re-derivation instead of a starting point — which is where drift enters.
Neither line competes with anything: the live next action is the field on the
project at privacyllc.dev and the live blockers are issues in the tracker, while
these say what both were **at this date**. A record of then never disagrees with
a record of now.

**Append-only by convention.** Correcting an old entry rewrites the record of
what was known at the time, which is the one thing this file is for. If an entry
turns out to be wrong, add a later entry saying so; do not edit the first.

Note the Review trigger above says "nothing", deliberately. A dated log cannot
rot the way a description of current state can — the entries were true when
written and stay true. It is exempt from review for the same reason a receipt is.

## Entries

### 2026-08-18 — The wordmark got its space, and #28 closed

The owner supplied a redrawn lockup, `docs/design/dist/splash.webp`. It sets the
name as **Privacy: Period Tracker** — with the space after the colon — which is
the whole of what #28 asked for.

**It was necessary and not sufficient**, which is worth writing down because the
tempting move was to look at the new artwork and close the issue. #28's `Verify`
line names the two *derived* assets, not the lockup: the wordmark in
`docs/data/img/logo.webp` and `banner.webp` had to match `app_full_name`. Both
still carried the old spaceless form, because they were generated from the
earlier source months of decisions ago. Regenerated from the new lockup, checked
by cropping the colon out of each finished webp at 1350px wide and reading it.

**The banner is composed, never cropped.** The lockup is square and the banner
is 3:1, so a crop takes the ends off the wordmark — the exact trap the first pass
at these assets hit. A 660px square card centred on a 2176×725 field, same as the
existing asset did it. No flood-fill this time either: `splash.webp` has real
transparency where the earlier sources rendered their rounded corners against
black.

**`icon.webp` was deliberately left alone.** It carries no wordmark, it is the
same visual family, and #28 is about the name. Regenerating it would have been
churn dressed as consistency.

`BRAND_GUIDE.md` §10 carried a callout saying the drawn mark disagreed with the
written name. That statement is now false, so it says what happened instead, and
names the old lockup sources as superseded rather than deleting them — they are
the owner's files.

- **Closed:** #28.
- **Next action:** Batch 06 has #34, #35 and #37 left, and Batch 08 has #31 and
  #32. #37 is the smallest and is unblocked. #34 still carries the open product
  question about a forgotten PIN.
- **Blockers:** #9, the Command Center webhook, still needs a person. TalkBack
  has still never been run and no real lock screen has been looked at — both
  cheap, both never done.

### 2026-08-18 — A logging guard, and the leak it was not looking for

#38 asked for a guard that stops health data reaching a log. Writing it found a
worse problem than the one it was written for.

**The guard.** `checkNoHealthLogging` fails the build on any logging call in a
module that can see a cycle date. Two things make it a guard rather than a grep,
and both were live in this repository already: `PeriodApplication` passes
`android.util.Log.WARN` to WorkManager as a **constant**, which is not a log
call, and `ReminderWorker`'s KDoc says *"a `Log.d` in a worker is the kind that
survives"* — the comment explaining why there isn't one. A naive grep fails the
build on the clearest possible explanation, and the obvious fix is to delete the
explanation. So it matches a call shape and strips comments first.

Proved in both directions, per GUARDS.md §1: injecting a real `Log.d` into
`CycleRepository` produced **exactly one** failure, and a comment containing both
`Log.d(` and `println(` stayed green.

It also failed its first run for a reason worth recording — it walked
`domain/*/bin/`, an IDE output directory that is gitignored and holds stale
copies of test files, and reported a `println` in one of them. A guard that
fails on untracked build output is a guard somebody switches off.

**And the thing it could never have caught.** `Prediction`'s `init` block
interpolated dates into its `require` messages:

    require(!windowStart.isAfter(windowEnd)) { "window start $windowStart is after window end $windowEnd" }

Five predicted dates across three messages, in an `IllegalArgumentException` —
the one string a crash reporter is guaranteed to collect without anybody
choosing to log it. §45 says "do not include raw cycle dates in crash reports",
and this was the app doing exactly that, with no logging statement anywhere near
it.

The same shape applies to every data class: `toString()` renders every field
into any string that touches it. `PeriodRecord`, `SpottingRecord`,
`CycleRecord`, `Prediction` and `NotYetObservation` now override it — ids and
lengths survive, dates do not, because an id identifies a row without describing
a person and a cycle length says nothing about when. `NoDatesInDiagnosticsTest`
pins all seven cases, and was itself proved to fail.

**The release build was driven, not reasoned about.** `assembleRelease` is
unsigned, so it was signed with the debug keystore and installed alongside the
debug build. Onboarding to a forecast, then logging a period: **zero ISO dates in
logcat, zero health words, and the only mentions of the package are the system's
own.** The screenshot confirms it reached a real forecast rather than failing
early, because "no logs" is trivially true of an app that did nothing.

- **Closed:** #30, #38.
- **Next action:** Batch 06 has #34, #35 and #37 left. #37, the privacy promise
  in Settings, is the smallest and needs only the screen that now exists. #35,
  export, is the bigger one and its trap is §45 again — an export is health data
  leaving the app, so it uses the Storage Access Framework rather than writing to
  shared storage. #34, app lock, still carries the open product question: what
  happens when somebody forgets their PIN, with an irreversible delete on the
  same screen.
- **Blockers:** #9, the Command Center webhook, still needs a person. TalkBack
  has still never been run and no real lock screen has been looked at. A
  docs/design/dist/splash.png — named bare, because it no longer exists under
  that name — appeared in the tree during this session and was untracked at the
  time. It turned out to be the redrawn lockup, and is now committed as
  `splash.webp`.

### 2026-08-18 — Batch 06 starts, and two defects that only a device could show

The designed Settings screen and Delete My Data both landed. Neither is the
interesting part of the day.

**A privacy control whose label did nothing.** The delete confirmation promises
"your reminder settings are unchanged", and proving that meant changing a
setting first — so I tapped "Maximum privacy" on a device and watched nothing
happen. `PrivacyRow` and onboarding's `PrivacyOption` both put `onClick` on the
`RadioButton` and left the row inert. The option deciding what a lock screen
shows could only be changed by hitting a 20dp circle, in the two places a user
ever chooses it. Fixed with `Modifier.selectable` on the row, which also merges
the semantics so TalkBack announces one option instead of a radio and two loose
strings.

It was found by trying to verify a different claim. That is worth noting on its
own: the check that found it was not looking for it.

**And the setting does survive deletion** — set to Maximum privacy, deleted
everything, still Maximum privacy. Now demonstrated rather than argued from the
fact that `core/datastore` is a separate store.

**A design I had wrong before writing it.** My first draft of `PrivacyViewModel`
cancelled the reminder schedule on delete, which seems obviously right and is
not. `ReminderWorker` reads the forecast each run and `NoData` maps to no
decision, so the scheduled work already does nothing while there is nothing to
say — and scheduling only happens from `ReminderCoordinator` and the settings
screen, so cancelling would have left reminders silently off until the user next
toggled something, long after they had logged a new period. Checked the call
sites instead of reasoning from the name.

**Also fixed, from the font-scale pass:** the bottom navigation wrapped its
labels mid-word at scale 2.0 — *"Calenda / r"*. `maxLines = 1` and an ellipsis.
That defect predates all of today's work; the font-scale gap is simply the first
thing that looked.

**Settings shows only the sections that have something behind them.** A
greyed-out "Delete My Data" tells a user that control over their own health data
exists and that they may not have it, which is a bad first thing for this
product to say. Recorded in `docs/design/README.md` so the next person adding a
row knows it was a decision.

Round 4 recorded in `docs/qa/`. Four rounds in, the pattern has not moved: every
defect of consequence has been found by a person using the app, and none by a
test.

- **Closed:** #29, #33, #36.
- **Next action:** Continue Batch 06. #38, the release-build logging guard, is
  independent of the rest and can go next — write the guard first and prove it
  fails, per `docs/architecture/GUARDS.md`, because three guards in this project
  have been green over the exact failure they claimed to catch. #35 export and
  #37 the privacy promise both need only the Settings screen, which now exists.
  #34, app lock, still carries an open product question: what happens when
  somebody forgets their PIN, given an irreversible delete sits on the same
  screen.
- **Blockers:** #9, the Command Center webhook, still needs a person. TalkBack
  has still never been run and no real lock screen has been looked at — and
  after today's find, the TalkBack gap looks more expensive than it did: two
  screens had merged-semantics problems nobody would see without it.

### 2026-08-18 — The onboarding artwork ships, and a plan I had argued for turned out to be wrong

All eight illustrations are in the app in both themes, every onboarding step has
art for the first time, and **#29 closes**. The interesting part is that the plan
I pushed hardest for is not the one that shipped.

**I argued for vectors and was wrong.** The issue said redraw the set as Compose
vector paths taking colour from theme tokens. That is the right answer for
artwork that does not exist yet — it is exactly what §42 prescribes and what the
placeholders did. It is the wrong answer for gradient landscapes with glow and
depth: there is no honest `VectorDrawable` of one, and the attempt would either
lose the drawing or produce path soup slower than the image. §42 objects to
*unnecessary* raster, and I had been reading it as objecting to raster.

The number settled it. All sixteen files at the height they are actually drawn
at cost **130 KB**: the release APK went 1.90 MB to 2.03 MB. I had been arguing
against a cost I never measured.

**The theme swap is resource resolution, not a branch.** `drawable/` and
`drawable-night/`, so Android picks the asset and the artwork follows a device
theme change with nothing of ours running. It also means a missing night asset is
invisible in light mode, which is why `OnboardingPreviews.kt` now has one entry
per illustration rather than a representative few.

**What only a device showed.** Each drawing is composed as a card with its own
rounded corner painted in, so the pixels outside that curve are the card's own
backdrop — near-black in the dark set. Rendered unclipped, every illustration had
four visible notches against the app background. Nothing in the build says so,
the previews are small, and it was obvious within a second of looking at a phone.
`Illustration` now clips just inside the painted curve.

**Two vectors stayed vectors**, and the line is worth keeping: the calendar
markers and `CycleProgressMark` are drawn *from data* — a marker's shape is what
a day is, and the progress arc is where the user actually stands in their cycle.
Good artwork does not make those into images. `CycleProgressMark` moved from
`Illustrations.kt` to `CycleMarkers.kt` to put that boundary in the file layout.

**Sizing is by height, not a square box.** The set does not share one aspect
ratio and a square would letterbox some and crop others. Height is also the
dimension that decides whether the primary button stays on screen, so steps 3 and
6 — three buttons and three option cards respectively — take 104 dp where the
others take 120–128 dp. Checked by driving all seven steps rather than by
reasoning about it.

Driven end to end on `PeriodMinSdk26` in both themes, no crash.

- **Closed:** #29.
- **Next action:** Batch 06 — Privacy and Security. File its issues first; the
  milestone is still empty. Biometric and PIN lock, export, irreversible delete,
  the privacy promise in Settings, and making §45's logging rules true in a
  release build.
- **Blockers:** #9, the Command Center webhook, still needs a person. The QA gaps
  are unchanged: no real lock screen has been looked at, TalkBack has never been
  run, and text has never been scaled — the last one now matters more, because
  every onboarding step has an illustration above its heading and nobody has seen
  that layout at the largest font scale.

### 2026-08-18 — The app ran at `minSdk` for the first time

A second emulator exists — `PeriodMinSdk26`, API 26, Pixel 6 — and the app was
built, installed and driven on it start to finish. Everything before today ran on
API 36, which the standing gaps list has said since Batch 01.

**It works.** Onboarding from *Get Started* to a first forecast, the Material 3
date picker, Today, Calendar, Insights and Settings, all rendering correctly on
Android 8.0. The forecast was right — 4 August plus 28 days is 1 September, an
11-day window, confidence honestly **Low** on one cycle of history — and
fertility declined to estimate rather than inventing one. No crash, and no
`NoSuchMethodError`, `VerifyError` or `NoClassDefFoundError` attributable to the
app. The one `NoClassDefFoundError` in logcat is
`com.google.android.googlequicksearchbox` failing to resolve `TracingController`,
an API 28 class, in its own process.

That is a genuinely useful negative result: the two `NewApi` bugs found in Batch
01 were exactly this shape and would have crashed here.

**Three mechanical traps, all now in the QA playbook** rather than in somebody's
memory:

1. **A windowed emulator dies with the session's X server.** The first one was
   killed by `XIO: fatal IO error on X server ":0"` mid-flow. `-no-window` has no
   such dependency and screenshots still work through `adb exec-out screencap`.
2. **`adb` regularly has three devices attached here**, because other projects
   keep their own emulators running, and a bare `adb shell` then fails with *more
   than one device/emulator*. The serial has to be resolved from the AVD name;
   assuming `emulator-5554` targets somebody else's work.
3. **The debug build's application id carries a `.debug` suffix**, so
   `monkey -p dev.privacyllc.period` aborts with *No activities found to run*
   after a successful install — which reads as a broken app rather than a wrong
   package name.

**And a free persistence result.** The emulator was killed and cold-booted with
onboarding half finished. The install survived, and the app restarted at the
beginning of onboarding with nothing partial committed — which is correct, and is
the first reboot evidence pass D has ever had.

**A guard failure of my own, from the entry above.** That entry named the bad
`forgejo-issue.py` path in backticks, and `doc-claims.sh` reads a backticked path
as a claim the file exists — so commit `ad085fb` shipped with the guard failing.
I had run it before writing the log entry and not after. The path is named bare
now, which is the convention `DOC_TRUST_MAP.md` already documents for
deliberately-absent files, and the guard reports 251 claimed paths all present.

- **Closed:** nothing. This closes no issue; it partly closes a standing QA gap,
  which lives in `docs/qa/ClaudeQACoverage.md` rather than the tracker.
- **Next action:** Batch 06 — Privacy and Security, unchanged. File its issues
  first; the milestone is empty. Biometric and PIN lock, export, irreversible
  delete, the privacy promise in Settings, and making §45's logging rules true in
  a release build.
- **Blockers:** #9, the Command Center webhook, still needs a person. Three of the
  four QA gaps are unchanged and remain the cheaper spend: nobody has looked at a
  real lock screen, TalkBack has never been run, and text has never been scaled.
  The fourth — nothing has run at `minSdk` — is now partly answered, though
  notifications, the instrumented suites and any multi-cycle history are still
  unreached at API 26.

### 2026-08-18 — A doc audit against the code: 57 wrong claims in eighteen files

No code changed. Every document in the tree was checked against the source, the
tracker and git history, and each finding was then handed to a second reader
whose job was to refute it — 74 raised, 12 refuted, 57 applied after dedup.

**The README described a skeleton.** Its Status table — the one place in this
repository a claim about what is built is allowed to live — still said "there is
no usable app yet", with `Not built` against Room, the four core screens,
fertility and notifications, and `No round run` against QA. Five batches had
shipped and three QA rounds had run. The rename commit touched the file and left
the table alone, which is the whole failure mode in one line: a document gets
opened, edited for one reason, and its stale half is not what the editor was
looking at.

**Two guards were silently never firing.** `docs/architecture/README.md` and
`docs/design/README.md` both wrote their `Governs:` field as prose —
`the Gradle module graph`, `the design tokens in core/designsystem`. Neither
contains a path token, so `doc-triggers.py` reduced them to globs that match
nothing, and because each file had one real glob it was classed as
path-governing rather than subject-governing — the one state the script's own
header calls invisible. Editing a Room entity never fired the document that owns
the migration table; editing the palette never fired the document that owns
colour. Both now fire, checked by running the script rather than by reading it.

**`SECURITY.md` claimed four things the app does not do.** App lock listed among
what works offline, biometric/PIN gating described as protecting app launch, the
incognito launcher as existing, and Google Play Billing sitting in the third
parties table without the *not yet integrated* marker its two neighbours carry.
All four are Batch 06 and 07 work. A security document that describes unbuilt
protections as shipped is worse than one that omits them, because it is the
document somebody checks *instead of* the code.

**The advertising boundary was overstated in the same way, in two files.** Both
`SECURITY.md` and the README said the ads module declares no dependency on the
cycle database and a guard proves it. There is no ads module. What exists is
better than the prose and had to be described accurately: `":core:ads" to
emptySet()` is pre-declared in the root build script, stricter than the sentence
it replaced, and matching no module until Batch 07 — which is exactly why the
guard is proved by injection rather than trusted.

**Smaller, and each a real trap.** `WORK_CYCLE.md` told the reader to run a
`forgejo-issue.py` under docs/architecture/scripts/ — a template path that does
not exist here, named bare above because `doc-claims.sh` reads a backticked path
as a claim the file is present and this sentence says the opposite. The guard
missed it in `WORK_CYCLE.md` for the neighbouring reason: it reads backticked
prose, not fenced code blocks. `ClaudeReport.md`'s Round notes said "No rounds
yet" after three rounds, because `ClaudeQAPlan.md`'s after-a-round list never mentioned that
section; both are fixed, the playbook first. The instrumented-test count was
eight in three places and is four. `HISTORY.md` said the repository had no code
and that nothing had been tried and dropped, when three approaches had. The
brand guide's wordmark callout had been rewritten by the rename into saying the
artwork has "no space" while printing the spaced form — destroying the only
counter-example in the repository.

**What was deliberately left alone.** `ClaudeReport.md`'s last verified build
SHA stays at `0451fbe`: no QA round has run since, and moving it to `HEAD` would
claim a verification nobody performed. Every `DEVELOPMENT_LOG.md` entry stays as
written. `PRODUCT_PLAN.md` §39's teal palette stays superseded rather than
rewritten — the routing table now says so at the point a reader would go looking.

- **Closed:** nothing — these were doc defects, not tracker deliverables.
- **Next action:** Batch 06 — Privacy and Security, unchanged. File its issues
  first; the milestone is empty. Biometric and PIN lock, export, irreversible
  delete, the privacy promise in Settings, and making §45's logging rules true in
  a release build. `SECURITY.md` now describes that surface as unbuilt, so the
  batch has an accurate starting description for the first time.
- **Blockers:** #9, the Command Center webhook, still needs a person. The four QA
  gaps are unchanged and still the better spend: no real lock screen has been
  looked at, TalkBack has never been run, text has never been scaled, and nothing
  has run at `minSdk` 26.

### 2026-08-18 — Renamed to Privacy: Period Tracker

"Period" was always a working name — `PRODUCT_PLAN.md` §55 said so — and the real
identity arrived with the brand guide. Everything that called the project Period
now calls it **Privacy: Period Tracker**.

**The rename was mostly about deciding what NOT to touch.** "Period" is the
product name and the central domain word at the same time. `PeriodRecord`,
`PeriodWriteResult`, `confirmPeriodStart`, the `period_records` table and the
button reading "Started period" all describe a menstrual period rather than a
product — 239 references, every one of them left alone. A find-and-replace would
have turned the data model into nonsense. Sixteen files changed in total.

Also deliberately unmoved, and written down so the absence reads as a decision:

- **The package `dev.privacyllc.period` and `applicationId`.** They already read
  correctly under the new name — `privacyllc` is the company, `period` the app —
  and changing them would rewrite 68 files, rename the Room schema directory and
  break the hardcoded path in `schema-guard.sh`.
- **`period.db`.** Renaming a database file orphans the data on every device
  that already has it. The emulator's existing install opened fine afterwards,
  which is the proof.

**The repository was renamed in place**, not recreated: `null/Period` →
`null/Privacy-Period-Tracker`, keeping all 30 commits, 27 issues, 8 milestones
and 4 labels. Counted on both sides rather than assumed, because "a rename is
lossless" is exactly the sort of thing that is true until it is not.

**Three names have to agree**, and only two of them are obvious: the Forgejo
repository, the git remote, and the Command Center's `forgejoRepo` mapping. The
third is the silent one — a stale mapping degrades to *"pointing at a repository
that does not exist"* on the next reconcile and the site quietly stops counting.
All three verified, and the reconcile afterwards reported `0 pointing at a
repository that does not exist`.

**The Command Center slug could not be renamed.** `PATCH` accepted a `slug` field
and ignored it; `period` still resolves and `privacy-period-tracker` returns 422.
It is an internal key, invisible on the card, and recreating the project to
change it would throw away its history — so it stays, recorded here rather than
retried later by somebody who assumes it was missed.

**One inconsistency created on purpose.** The canonical name has a space after
the colon; the supplied wordmark does not. `BRAND_GUIDE.md` §10 now says the
space form and says plainly that the drawn mark disagrees. Filed as #28 rather
than papered over, because redrawing a lockup needs an artist.

- **Closed:** nothing — this is a rename, not a deliverable. #28 filed.
- **Next action:** Batch 06 — Privacy and Security, unchanged by the rename. File
  its issues first; the milestone is empty. Biometric and PIN lock, export,
  irreversible delete, the privacy promise in Settings, and making §45's logging
  rules true in a release build.
- **Blockers:** #9, the Command Center webhook, still needs a person. Its body
  named the old repository path and has been corrected in the tracker, so
  whoever picks it up gets a command that works. The four QA gaps are unchanged
  and still the better spend: nobody has looked at a real lock screen, TalkBack has never been run,
  text has never been scaled, and nothing has run at `minSdk` 26.

### 2026-08-18 — Batch 05 shipped, and the app got its real brand

Reminders landed and the milestone closed. **Five of eight batches are done, and
exactly one issue is open in the whole tracker** — #9, the webhook, which needs a
person.

**Notifications, and the two Android behaviours that leak if you trust the
docs.** `NotificationCopy` is a pure function, so every kind × every mode is
tested exhaustively without an emulator — including the action labels, which §31
points out are visible text too. A perfectly discreet body under a button
reading "Started my period" leaks anyway.

Then the device found what the unit tests could not:

1. **A private notification with no public version does not blank the lock
   screen — it shows the private text.** `NotificationText` therefore has no
   nullable title, and an instrumented test asserts every kind attaches one.
2. **A notification channel is immutable after creation.** Importance and
   lock-screen visibility cannot be changed, so one shared channel would have
   kept whatever the user's first privacy mode set, forever. Switching from
   Direct to Maximum privacy would have *appeared* to work and changed nothing.
   One channel per mode now.

**A third guard failed its first proof.** `checkPermissions` — new, and worth
having, because adding WorkManager silently brought four permissions that appear
in the Play listing — read a stale merged manifest because it did not depend on
the task that writes one. An injected `SCHEDULE_EXACT_ALARM` went unnoticed.
That is the schema guard, the boundary guard and now the permission guard: three
for three. **Assume a new guard is broken until it has been watched failing.**

**And a mistake of mine worth keeping.** While proving the pre-commit fix I
committed a throwaway and ran `git reset --hard HEAD~1`, which did not undo the
push the post-commit hook had already made and silently discarded the
uncommitted fix I was mid-proof on. Reconciled forward rather than rewriting
published history. Commit the work before proving the guard.

**The brand arrived mid-session.** The owner supplied a full visual guide and
artwork, which answers #8 — the three marks an agent must not fake now exist
because a person made them. Converted to the required webp with two things
handled rather than blindly transcoded: the sources render their rounded corners
against black, and the lockup is square so a 3:1 crop would have cut the wordmark
in half.

The guide **supersedes §39's colour direction**, and one conflict is real: §39
wants a muted teal fertile window and the guide is plum-and-rose throughout with
a pink for fertility. The guide wins, and it is safe for it to win *because the
calendar's states differ in shape rather than colour* — which is what §43
actually requires. Written down in `docs/design/README.md` rather than left to be
found.

- **Closed:** #8, #24, #25, #26, #27 — and the `Batch 05 — Notifications`
  milestone.
- **Next action:** Batch 06 — Privacy and Security. File its issues first; the
  milestone is empty. The work is biometric and PIN lock, export, irreversible
  delete, the privacy promise in Settings, and making §45's logging rules true in
  a release build. Much of the groundwork exists — `deleteAllHealthData` is
  written and tested, backup is already excluded in the manifest — so this batch
  is largely surfacing what the data layer can already do, plus the designed
  Settings screen the Batch 05 working surface is standing in for.
- **Blockers:** One issue, and it needs a person: #9, the Command Center webhook.
  Until it is registered an opened `P0` raises no alert at all. The QA gaps are
  now the more pressing thing: **nobody has looked at an actual lock screen**,
  TalkBack has never been run, text has never been scaled, and nothing has run
  at `minSdk` 26. All four are cheap and none has ever been done.

### 2026-08-18 — Batch 04 shipped: fertility that declines, and a hook that refused every deletion

Three issues closed and the milestone with them. Four of the eight batches are
now done.

**Fertility, and the decision that made it worth shipping.** Ovulation is
estimated a luteal phase before the *predicted* next period — §17 asks for that
direction because the luteal phase is the stable half of the cycle — and the
window opens five days before it and closes one after. The uncertainty is
inherited from the forecast rather than invented.

The first version was arithmetically correct and useless. A user one cycle into
the app was shown a fertile window of **8 Aug – 24 Aug**: seventeen days, over
half a cycle, dressed up as a feature. So the estimate now returns null past a
usable uncertainty and the screen says *"Not enough history to estimate"* with a
reason to keep logging. Three stable cycles later the same user gets 12 Aug – 20
Aug, which is worth reading. Both states were checked on a device.

That is the third instance of one pattern, so it is now written into
`docs/architecture/README.md` as a rule rather than a coincidence: **the app
declines rather than stretches.** Accuracy figures wait for three scored
forecasts; averages wait for two intervals; fertility waits for a forecast tight
enough to hang off.

**§18's prohibition is a type.** `FertilityLikelihood` has LOWER, HIGHER and
UNKNOWN and no fourth value, and a test asserts no label contains a permission
word — so adding "safe" is a deliberate act with a failing test rather than a
slip in a string.

**Another greyscale collision.** The ovulation star was centred and sat directly
behind the numeral; in greyscale the "18" and the mark merged. Ovulation is now
the fertile ring plus a small star low in the cell, which is also the more honest
picture — that day *is* inside the window.

**The hook refused every deletion-only commit.** `secrets.sh` exits 2 for
"nothing was scanned", which is the correct answer for a commit that only
deletes files. The hook treated any non-zero as a refusal and printed *"possible
credential in the staged changes"* over a plain `git rm`. Found while removing a
`bin/` directory Buildship had been writing — a directory full of `.kt` files,
which is the one kind of build output that does not look like build output in a
`git status`. It only got committed at all because a `.gitignore` edit was
staged alongside, which gave the scanner something to read.

**And a mistake worth recording rather than tidying away.** While proving the
fix, I committed a throwaway, then ran `git reset --hard HEAD~1` — which did not
undo the push the post-commit hook had already made, and silently discarded the
uncommitted hook fix I was in the middle of proving. The second proof then
failed for a reason that had nothing to do with the guard. Reconciled forward
rather than force-pushed. **Commit the work before proving the guard, not after.**

- **Closed:** #21, #22, #23 — and the `Batch 04 — Fertility` milestone.
- **Next action:** Batch 05 — Notifications. File its issues first; the milestone
  is empty. The work is WorkManager-scheduled reminders (§29, §30) with the three
  privacy modes from §28 — and the mode that matters is Discreet, already the
  stored default and already chosen in onboarding, so this batch is about the
  lock screen actually honouring it. **Pass F cannot be run until this lands**,
  and it is the pass that checks the most likely real privacy breach in this
  product.
- **Blockers:** Unchanged, both needing a person: the three branding marks (#8)
  and the Command Center webhook (#9). The three standing QA gaps are also still
  open and are getting more expensive the more UI exists — TalkBack has never
  been run, text has never been scaled, and nothing has run at `minSdk` 26.

### 2026-08-18 — Batch 03 shipped: every screen the app has, and three defects only looking could find

All six Batch 03 issues closed and the milestone with them. Period stopped being
a data layer with a debug surface and became something you can actually use:
onboarding that ends in a forecast, a Today screen whose six states each say
something different and true, two-tap logging, a calendar, and Insights.

**Placeholder artwork, as §42 asks for it.** Every illustration and calendar
marker is a Compose vector path behind a replaceable name — no raster anywhere
under `src/`. The visual language is overlapping circular forms and nothing
else, because §42's forbidden list is a product decision: this app gets opened
in public and a glance over a shoulder should learn nothing. Note the deliberate
contrast with `docs/data/img/`, where a placeholder is still forbidden and #8
stays open; `docs/design/README.md` now explains why the two differ rather than
leaving it looking inconsistent.

**Three defects, none findable by reading:**

1. **Dark mode was broken for the whole of Batch 01.** `PeriodTheme` never
   wrapped its content in a `Surface`, so any `Text` without an explicit colour
   inherited Material's default — black — and the app's background never
   painted. Light mode looked right by accident, because dark-on-cream is what
   was wanted anyway. 129 tests were green throughout.
2. **"Period ended" appeared to do nothing.** The logic was correct: a period
   that ends today still includes today, so the state genuinely does not change.
   The screen was identical afterwards and the button read as broken, which is
   worse than being broken somewhere visible.
3. **The today-underline collided with the spotting dot** on the one day that
   was both. Invisible in the colour screenshot and obvious the moment it was
   converted to greyscale — which is how §43 says to check, and why the check is
   written that way rather than trusting that shapes differ because they were
   designed to.

Two more came from tests doing their job: the typical-range quartiles were
indexed off `size` rather than `size - 1`, so a regular cycle with one long gap
was reported as "typical range 29–61 days" on the screen whose only job is to
say what has been learned; and Room's own executor meant a test's virtual clock
returned before the writes landed, which read as an empty database rather than
as a timing bug.

**The habit is now five pieces of work old and worth writing down as a rule: the
defects in this project are found by running it.** Three guards were green over
exactly what they claimed to check, dark mode was broken for a whole batch, and
a button looked broken while behaving correctly. None of it was visible in the
source.

- **Closed:** #15, #16, #17, #18, #19, #20 — and the `Batch 03 — Core UX`
  milestone.
- **Next action:** Batch 04 — Fertility. File its issues first; the milestone is
  empty. The work is estimated ovulation and the fertile window from the
  forecast and a configurable luteal-phase assumption (§17, §18), the calendar
  and Today states that already have their shapes and their `null` placeholders
  waiting, and the not-contraception disclaimer everywhere fertility appears.
  `CycleStatus` and `CalendarMarks` both already take fertility parameters and
  currently receive null — Batch 04 is largely filling those in rather than
  adding surfaces.
- **Blockers:** Unchanged. #8 needs the three branding marks drawn by a person.
  #9 needs the Command Center webhook URL and secret, which are not readable
  from this machine. Neither blocks Batch 04. Worth doing before much more UI:
  run TalkBack once, scale the font to maximum once, and run the app once on a
  device at `minSdk` 26 — all three are recorded as standing gaps and none has
  ever been done.

### 2026-08-18 — Batch 02 shipped: the prediction engine, and three bugs the tests found

All five Batch 02 issues closed and the milestone closed with them. The app now
ships the engine PRODUCT_PLAN.md §12 specifies rather than the prototype it was
explicitly labelled as.

**The shape is the design.** `PersonalPredictionEngine` keeps a discrete
probability distribution over candidate start dates, not a date with a margin.
The mode is the forecast, the window is the narrowest span holding 80% of the
mass, and a "Not yet" is the distribution conditioned on what the user said.
§13's requirement — that a "Not yet" updates the date, the window *and* the
confidence rather than shifting a fixed prediction by a day — is not extra work
in that design; it is the only thing that structure can do.

**It is better, as a number.** `EngineComparisonTest` scores both engines over
the §51 fixtures on every build: mean absolute error 0.67 against 1.00, and the
window contained the actual start 9 times out of 9 against 7.

**Coverage is the measure, not width — and measuring taught that.** The first
version of the comparison asserted the new windows must not be wider. It failed,
and it was the assertion that was wrong: where the personal engine is wider, it
is right to be, and the baseline answers a history with a suspected missing
period using a two-day window and misses. A window that misses is a broken
promise rather than a tight forecast.

**Three modelling bugs, each found by a test failing rather than by reading:**

1. Median absolute deviation alone reads a user alternating 25 and 37 days as
   perfectly consistent — half her deviations are zero. Twenty disagreeing
   cycles came back High, which is exactly the §15 rule about volume not buying
   confidence. Spread is now the larger of MAD and mean absolute deviation.
2. Recency weighting assumes the recent past predicts the near future. For a
   variable user that is false, and weighting it equally cost three days on the
   §51 variable fixture. Recency is now trusted in proportion to how much her
   cycles agree — which is a better statement of what recency weighting is
   actually for.
3. A fixed one-day floor on trend detection fired on a 42-day-cycle history
   whose medians differed by one day. One day is a real trend at 28 and rounding
   error at 42, so the floor is relative to the user's own spread.

That is now three consecutive pieces of work — the schema guard, the boundary
guard, and the engine — where the thing that found the defect was **running it,
not reading it**. Worth stating as a habit rather than a coincidence.

**Wired through, not just tested.** `PredictionInput` carries recent absolute
errors and the repository feeds scored errors back in. Without that the app
would store every error it makes and never read one back — measuring accuracy
rather than learning from it, with §12 step 5's widening happening only in a
unit test.

- **Closed:** #10, #11, #12, #13, #14 — and the `Batch 02 — Prediction Engine`
  milestone, which closing the last issue does not do.
- **Next action:** Batch 03 — Core UX. The onboarding flow in §19, the designed
  Today screen and its six dynamic states in §21–§22, period start and end
  logging in §23–§24, the calendar in §26 and Insights in §27. The working
  surface built in Batch 01 is deliberately ugly and says so on screen; it is
  the thing Batch 03 replaces. Before starting, file the Batch 03 issues — the
  milestone exists and is empty.
- **Blockers:** Unchanged and both need a person. #8, the three branding marks,
  which an agent must not fake. #9, the webhook, whose URL and secret are not
  readable from this machine — until it is registered an opened `P0` raises no
  alert at all. Neither blocks Batch 03.

### 2026-08-18 — Batch 01 foundation: seven of nine issues, and three guards that were wrong

Room, DataStore, the repository layer, period CRUD end to end on a device, and
the module boundary guard. #3 to #7 closed; #8 (branding) and #9 (webhook) are
the two that need a person rather than an agent.

**What was built.** `core/database` with the four entities from §10, DAOs
returning `Flow`, and the schema exported and committed. `core/datastore` for
settings, deliberately separate from the cycle database so Delete My Data cannot
reset a privacy choice the user made. `core/data` as the seam: domain types out,
cycles derived rather than stored, the forecast a function of the data instead
of a field somebody has to refresh. Hilt wiring and a working Today surface that
says "Batch 01 · working surface" so nobody mistakes it for the designed screen.

**Three guards were written, and all three were wrong at first.** This is the
day's real lesson and it is worth carrying forward:

1. `SchemaTest` looked like a Room schema-drift guard. Room regenerates the
   schema export during compilation, so both sides of every comparison agreed by
   construction — adding a column without bumping the version left it green.
   `scripts/schema-guard.sh` asks git instead, which Room cannot overwrite.
2. `checkModuleBoundaries` reported "7 modules checked, no violations" while
   checking nothing: the root project is configured before its subprojects, so
   every configuration read as empty. Caught by `prove-guard.sh` on its first
   run. Collection moved to `afterEvaluate`, and the task now throws rather than
   passing when it examined nothing.
3. The repository let `SQLiteConstraintException` escape into
   `viewModelScope.launch`, so **tapping the primary button twice killed the
   app** — found by hand on an emulator, with 70 unit tests green.

Each was caught by actually trying to break it. None would have been caught by
reading the code, and two of them would have been trusted for months.

**Two more bugs came from wiring the guard into `./gradlew check`**, which ran
Android lint for the first time: `LocalDate.ofInstant` and `LocalDate.EPOCH` are
API 34 and `minSdk` is 26. Both sit on the recalculation path — a crash on every
device below Android 14, invisible to the unit tests and to an API 36 emulator.

**QA.** Round 1 recorded as partial in `docs/qa/`. Passes A and B green, C and D
and H partial, the rest not run and each saying why.

- **Closed:** #3, #4, #5, #6, #7
- **Next action:** Batch 02 — replace `BaselinePredictionEngine` with the engine
  §12 specifies: recency weighting, a robust centre, variability-driven windows,
  trend detection, and "not yet" as a real conditioning step rather than a floor
  on the window. The §51 acceptance tests already exist and must keep passing
  against the new engine, which is what makes the replacement demonstrably
  better rather than merely different. Before that, one cheap thing worth doing:
  run the app once on a device at `minSdk` 26, because nothing here ever has.
- **Blockers:** None for code. #8 needs the three branding marks drawn — an
  agent must not fake them, so the project card shows an initials tile until
  somebody does. #9 needs the Command Center's webhook URL and secret, which are
  not readable from this machine; until it is registered an opened `P0` raises
  no alert at all.

### 2026-08-18 — Template adopted; Kotlin/Compose skeleton builds

Period went from a bare directory holding one specification file to a git
repository with the standard documentation tree, a tracker, and a project that
compiles. Adoption followed `Projects/Template/START-HERE-New-Project.md`.

**Documents.** `scaffold.sh` created 19 paths, 0 skipped. The specification moved
from `Docs/period_tracker_product_plan.md` to `docs/planning/PRODUCT_PLAN.md`
unchanged in substance, with a status header added; the capitalised `Docs/` is
gone, since every script and the Command Center expect the lowercase tree. Every
scaffolded document was filled in for Period rather than left with placeholders.
docs/OPERATIONS.md was deleted — an offline app is not a deployed service.
`docs/DOC_TRUST_MAP.md` was written last and describes what is actually here,
including a section naming what this project deliberately does **not** have.

**Code.** Four Gradle modules: `app`, `core/designsystem`, and `domain/cycle`
and `domain/prediction` as `kotlin("jvm")` so the engine is testable without an
emulator. 17 tests pass, 12 of them the acceptance cases from `PRODUCT_PLAN.md`
§51. `BaselinePredictionEngine` is a robust-median prototype and is explicitly
not the product — it exists so Batch 02's replacement can be shown to be better
rather than merely different.

**Three things that cost time and are worth knowing next session:**

- **AGP 9 ships Kotlin built in.** Applying `org.jetbrains.kotlin.android` is now
  a hard error, not a redundancy. The Compose compiler plugin is still separate.
- **Current AndroidX requires `compileSdk 37`.** Only up to 36 was installed;
  `platforms;android-37.0` and `build-tools;37.0.0` were installed into
  `~/Android/Sdk`. `targetSdk` stays at 36 — Play's floor from 2026-08-31 — and
  the two being different is deliberate, not an oversight to tidy up.
- **Versions were verified, not inherited.** Kotlin 2.4.10, AGP 9.3.1, Gradle
  9.7.0, Compose BOM 2026.08.00, Room 2.8.4, Hilt 2.60.1 — each checked against
  its official source today, which `PRODUCT_PLAN.md` asks for rather than
  trusting its own numbers.

**Tracker.** Eight milestones opened, `Batch 01 — Foundation` through
`Batch 08 — Polish`, and nine issues filed under Batch 01 only. Seven milestones
are deliberately empty: the roadmap is genuinely known and worth being visible,
but the work items under it are not, and inventing them would make every tracker
percentage permanently wrong. `forgejo-issue.py check` warns about this, and the
warning is correct about the mechanism and expected here.

- **Closed:** #1, #2
- **Next action:** Start issue #3 — core/database with Room entities for
  `PeriodRecord`, `SpottingRecord`, `PredictionRecord` and `NotYetObservation`,
  DAOs returning `Flow`, schema export committed, and a version-1 migration test
  that proves the harness works before there is a migration that matters. Its row
  goes in `docs/architecture/README.md`'s migration table in the same commit.
- **Blockers:** None for the code. Two things need a person rather than an agent:
  the three branding marks (#8), which cannot be drawn here and must not be
  faked, and the Command Center webhook (#9), whose URL and secret are not in any
  credential file readable from this machine. Without the webhook an opened `P0`
  raises no alert at all — it waits for the next reconcile.