17cddb2a61
Asked whether encryption at rest could be added. It can, and it should not be yet — so the reasoning goes in the document that owns the claim, before it is forgotten and re-derived from scratch. The architecture decides it. ReminderCoordinator collects Room flows at every process start, including processes started with no Activity after a reboot, and ReminderWorker reads the forecast on a schedule. The key would have to be readable with no user present, which is the availability condition the platform key already has. A key anything running as this app can reach unattended defends a file, not a process — and against every adversary this document already lists, it adds nothing. What it would genuinely add is narrow: a file copied off the device and read elsewhere, a phone with no screen lock, and crypto-shredding on delete. The cost is about +1 MB downloaded and +2 MB installed on a 2 MB app, and a new class of total loss — a Keystore key can be lost in the field, platform backup is off, and there is no telemetry that would tell us it happened. Today a database that will not open is a bug. Afterwards it would be somebody's history. The condition that reverses it is written down too: a key bound to the app lock's user secret, once export has given the user a copy they control. BRAND_GUIDE carried an artwork brief reading "explaining encrypted local data storage" — a false claim waiting for somebody to draw it, on the one subject where a padlock reads as a promise. Replaced with what is true and is a better story anyway: the data never leaves, so there is no server to breach and nothing to sell. SECURITY_CHECKLIST gains the row that would have caught it. Nothing shipped ever claimed encryption; grep over app, core and domain for strings and illustrations comes back empty. This closes the gap between that and the documents. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> |
||
|---|---|---|
| .githooks | ||
| app | ||
| core | ||
| docs | ||
| domain | ||
| gradle | ||
| scripts | ||
| .gitignore | ||
| README.md | ||
| build.gradle.kts | ||
| gradle.properties | ||
| gradlew | ||
| gradlew.bat | ||
| settings.gradle.kts | ||
README.md
Privacy: Period Tracker
Status: Draft
Owner: _null
Last reviewed: 2026-08-18
Governs: README.md as the project-facing overview for Privacy: Period Tracker
Review trigger: The first buildable feature release; any change to the stack, the
privacy promise, or how the project is built and run
A private Android period tracker that learns your cycle rather than the average person's — and never sells your data.
What it is | Status | Build and run | Repository map | Project docs | Agent notes
{ Android / Google Play | Kotlin + Jetpack Compose | Room, offline-first | Personalized prediction with an honest window | Discreet notifications | No account, no server, no data sale }
The core loop is:
Track → Learn → Predict → Remind → Learn again
What it is
A focused tracker that answers one question well: when is my next period likely to start? It records confirmed period dates, learns the individual's pattern from them, and produces a most-likely date with a window and a confidence label — never a bare date presented as fact. From that it estimates ovulation and the fertile window, and it asks discreetly whether the period started, using both yes and not yet to improve the next forecast.
Two promises hold the product up:
Your period. Better predicted. — once there is enough personal history, the app must not fall back to a generic 28-day cycle. A user recording 34, 35, 36, 34, 35 who is predicted 28 is a core product defect, not a tuning issue.
Your cycle belongs to you. We will never sell period history, fertility information, ovulation estimates, cycle predictions or personally identifiable information — to advertisers, data brokers or anyone else.
The second is held structurally rather than remembered, and the rule was written
before the code it constrains: checkModuleBoundaries in the root
build.gradle.kts already carries ":core:ads" to emptySet(), so when the ads
module arrives in Batch 07 it may declare no project dependency at all —
stricter than "nothing from the cycle database or the prediction domain". It is
not in settings.gradle.kts yet, so today the rule matches no module, which is
why the guard is proved against injected violations rather than trusted.
What it deliberately is not — no community, no pregnancy mode, no chatbot, no article feed, no symptom encyclopedia, and not contraception — is in docs/planning/PROJECT_PLAN.md.
Status
Five of the eight batches are done. Foundation, prediction engine, core UX, fertility and notifications have landed; privacy and security (Batch 06) is the next work. Every row below cites the file or test that proves it.
| Surface | Status | Evidence |
|---|---|---|
| Documentation tree and tracker convention | Adopted | this tree; milestones and issues in the tracker |
| Gradle / Kotlin / Compose project | Builds | ./gradlew assembleDebug and assembleRelease both pass |
| Material 3 theme and tokens | Built | core/designsystem |
| Four-tab navigation shell | Built | app/src/main/kotlin/dev/privacyllc/period/navigation/PeriodApp.kt — Today, Calendar, Insights, Settings, each wired to its real screen |
| Cycle model and interval derivation | Built | domain/cycle (13 tests); domain/prediction/src/main/kotlin/dev/privacyllc/period/domain/prediction/IntervalAnalysis.kt (12 tests) |
| Prediction engine | Built — personalized | PersonalPredictionEngine, wired in app/src/main/kotlin/dev/privacyllc/period/di/DataModule.kt; the 12 acceptance tests from PRODUCT_PLAN §51 run against both engines (PersonalAcceptanceTest, BaselineAcceptanceTest), and EngineComparisonTest scores the personal engine against the retained baseline every build |
| Room persistence, DataStore | Built | core/database (schema v1 exported, SchemaTest + scripts/schema-guard.sh), core/datastore, core/data |
| Onboarding, Today, Calendar, Insights | Built | app/src/main/kotlin/dev/privacyllc/period/feature/ — onboarding, today, calendar, insights; OnboardingViewModelTest, TodayViewModelTest, TodayUiStateTest |
| Fertility window and ovulation estimate | Built | domain/prediction/src/main/kotlin/dev/privacyllc/period/domain/prediction/FertilityEstimate.kt, 11 tests; shown on Today and Calendar |
| Discreet notifications | Built | core/notifications (24 JVM tests), instrumented NotificationPrivacyTest |
| App lock, export, irreversible delete, monetization | Not built | Batches 06–07 |
| QA | Round 3 run, partial | docs/qa/ClaudeReport.md — partial at 0451fbe; TalkBack, text scaling, minSdk and a real locked screen still unreached |
BaselinePredictionEngine is still in the tree, but it stopped being the
product in Batch 02. DataModule provides PersonalPredictionEngine — the
recency-weighted, trend-aware, "not yet"-conditioned engine PRODUCT_PLAN §12
specifies — and the baseline is now the control: EngineComparisonTest scores
both over the §51 fixtures every build, so "the new engine is better" is a number
rather than an opinion.
Build and run
Prerequisites: a JDK 21 and the Android SDK with platform 37 and
build-tools 37.0.0 installed, ANDROID_HOME set.
git config core.hooksPath .githooks # per clone, every clone — see below
./gradlew test # JVM suites, no emulator, ~1s
./gradlew assembleDebug # app/build/outputs/apk/debug/
./gradlew assembleRelease # minified, unsigned
compileSdk is 37 because the current AndroidX libraries require it;
targetSdk is 36, Google Play's floor for new apps from 2026-08-31. They are
deliberately different — raising targetSdk opts the app into runtime behaviour
changes and is a tested decision, not a build fix.
git config core.hooksPath .githooks is per clone. Without it the hooks are
not installed and fail silently, which is the failure mode they exist to
prevent. post-commit pushes; see
docs/architecture/githooks/README.md.
Repository map
app/ application module, MainActivity, navigation shell, DI
core/designsystem/ Material 3 theme and colour tokens
core/database/ Room entities, DAOs, converters, the exported schema
core/datastore/ user preferences that are not health history
core/data/ CycleRepository — the only module that touches a DAO
core/notifications/ reminder copy, privacy modes, WorkManager scheduling
domain/cycle/ pure Kotlin — period records, cycle derivation
domain/prediction/ pure Kotlin — the forecast, window and confidence
scripts/ six from the template, plus schema-guard.sh, our own
.githooks/ pre-commit, commit-msg, post-commit
docs/ product, architecture, design, brand, QA, security, history
domain/* are kotlin("jvm") modules and cannot see the Android SDK. That is
on purpose: the prediction engine is the product, so it needs the most tests,
and tests that need an emulator are tests that do not get run.
Project docs
Detailed procedures belong in docs; open work belongs in the tracker, not in this README.
| Doc | Purpose |
|---|---|
| docs/DOC_TRUST_MAP.md | Which document owns which answer, and which source wins when records disagree. Read this first. |
| docs/planning/PRODUCT_PLAN.md | The full V1 specification — prediction requirements, screens, copy, compliance |
| docs/planning/PROJECT_PLAN.md | The short vision, the stack and its reasons, and what this is deliberately not |
| docs/WORK_CYCLE.md | What happens at the end of a piece of work |
| docs/architecture/README.md | Modules, boundaries, data shapes, migrations |
| docs/design/README.md | Tone, and the four rules that settle design arguments |
| docs/security/SECURITY.md | Threat model, the advertising boundary, logging rules |
| docs/TOOLS.md | Which script to run, and which ones can stop you |
Where the tracker is
Milestones are batches, issues are deliverables, and severity labels are exactly
P0, P1, P2 and release-blocker. Credentials come from the environment,
never from this repository:
set -a; . ~/.openclaw/docker-registry.env; set +a
python3 scripts/forgejo-issue.py list
Two traps that cost an hour each otherwise: Cloudflare 1010-blocks clients that
do not look like a browser or curl, so every request needs
User-Agent: curl/8.5.0 — forgejo-issue.py sends it and anything new must
too. And /issues returns pull requests unless type=issues is passed.
Agent notes
- Product truth comes from the code and the tracker before prose.
- Do not keep a work list in this README or anywhere else in
docs/. - Finish with docs/WORK_CYCLE.md, every time: close what you finished with the evidence, close the milestone if the batch landed, update the documents the change triggered in the same commit, push, log the entry, then reconcile and write the summary and next action.
- Nothing on privacyllc.dev writes itself except the tracker counts and the pushed docs.
- Do not claim a feature is built unless you can cite the file, test or screenshot that proves it. The status table above is the standard.
- Verify current stable versions before changing the toolchain. The ones in
gradle/libs.versions.tomlwere checked against the official sources on 2026-08-18; PRODUCT_PLAN.md asks for that check rather than for its own numbers to be trusted. - Never put a cycle date, a prediction or a fertility state into a log, an analytics event, or an ad request.