DevVault

A developer identity layer — project memory, GitHub signal, and stack evolution in one local-first app.

Why

GitHub shows commits. Nothing shows what you decided, why you chose a stack, what you shipped versus abandoned, or how your technical identity evolved over time. DevVault fills that gap. Your data never leaves your device.

Screens

Screen	What it does
Home	Auto-generated developer type string ("KMP developer. Shipping actively. 2 shipped."), active project cards, GitHub pulse line
Projects	Full project list with filter tabs (All / Building / Shipped / Paused / Abandoned), status badges, tech stack chips, add/edit bottom sheet
GitHub	Consistency score (0-100), language breakdown bar chart, active repos, pull-to-refresh, offline cache banner
Stack	Timeline view of technologies grouped by year, filterable by status (Comfortable / Learning / Shipped With / Dropped)
Settings	Placeholder — wired into navigation, not yet implemented

Project Detail is also a placeholder (navigated to from project cards, shows ID only).

Three Pillars

Project Memory — Every project you've ever touched. Name, status, platforms, tech stack, decision notes, GitHub/live links. CRUD through a bottom sheet form. Local SQLDelight database.

GitHub Signal — Connect a username. Fetches public repos, per-repo language bytes, and weekly commit activity via the GitHub API. Calculates a consistency score from the last 12 weeks. Aggregates language usage across your top 10 most-recently-pushed repos. Caches results for 1 hour with stale fallback on network failure.

Stack Evolution — Manually tag technologies with a status and date range. Grouped into a visual timeline by year. Filterable.

The full product and technical document is in DevVault.md.

Tech Stack

Tool	Purpose
Kotlin Multiplatform	Shared business logic across Android and Desktop
Compose Multiplatform	Shared UI
Ktor Client	GitHub REST API calls
SQLDelight	Typesafe local database (multiplatform)
kotlinx.serialization	JSON parsing for API responses and cache
kotlinx.coroutines	Structured concurrency + Flow
DataStore Preferences	Key-value storage (username, display name)
Koin	Dependency injection
kotlinx-datetime	Epoch/time parsing for GitHub timestamps

Architecture

Three Gradle modules:

androidApp/    — Android entry point (MainActivity, MainApplication, Koin bootstrap)
desktopApp/    — Desktop JVM entry point (Window + Koin, post-MVP)
shared/        — All shared code
  commonMain/  — Data, domain, presentation, DI (all platform-agnostic)
  androidMain/ — AndroidSqliteDriver, DataStore context, platform Koin module
  jvmMain/     — JdbcSqliteDriver, JVM DataStore path, platform Koin module

Within shared/commonMain:

data/
  local/       — SQLDelight schema (.sq files), DatabaseDriverFactory (expect/actual),
                  DataStore factory (expect/actual), entity-to-domain mappers
  remote/      — Ktor GitHubApiClient, DTOs (RepoDto, UserDto, CommitActivityDto)
  repository/  — GitHubRepository (cache-first), ProjectRepository, StackRepository
domain/
  model/       — Project, GitHubSignal, TechEntry data classes
  util/        — ConsistencyCalculator
presentation/
  home/        — HomeScreen + HomeViewModel (developer type generation lives here)
  projects/    — ProjectsScreen, AddEditProjectSheet, ProjectDetailScreen (placeholder),
                  ProjectsViewModel
  github/      — GitHubScreen + GitHubViewModel (error/empty/loading/success states)
  stack/       — StackScreen, AddTechSheet, timeline components, StackViewModel
  settings/    — SettingsScreen (placeholder)
  navigation/  — Screen sealed class (lightweight, no nav library)
  theme        — DevVaultTheme (Material3 light), status colors, spacing constants
di/            — AppModule (Ktor, repositories, ViewModels), platform modules

Navigation is a simple sealed class with mutableStateOf<Screen> — no Compose Navigation library. Bottom nav bar pushes detail screens (ProjectDetail, Settings) on top with back handling.

Setup

Prerequisites

• Android Studio (Ladybug or later)
• JDK 11+

Run on Android

./gradlew :androidApp:assembleDebug

Or use the Android Studio run configuration on an emulator/device (API 26+).

Run on Desktop

./gradlew :desktopApp:run

Tests

./gradlew :shared:jvmTest
./gradlew :shared:testAndroidHostTest

GitHub API (optional)

DevVault works without a GitHub token — it uses the public API which allows 60 requests/hour. For higher limits, add a Personal Access Token in local.properties:

github.pat=ghp_your_token_here

This gets read into BuildConfig.GITHUB_PAT and injected into the Ktor client via KOIN.

Tech Stack Detail

The GitHub API layer fetches four things:

1. Public repos — sorted by pushed_at, top 50
2. Per-repo languages — fetched for the 10 most recently pushed repos (byte counts aggregated into percentages)
3. Commit activity — weekly commit counts from /stats/commit_activity for those same 10 repos (handles the GitHub 202 "computing" response with retries)
4. Consistency score — calculated from the last 12 weeks of aggregated commit data: 70% weight on active weeks ratio, 30% weight on average commits per active week

The caching strategy: check SQLDelight cache on load, serve if < 1 hour old, fetch fresh otherwise. On network error, serve stale cache with a banner. On no cache + no network, show an empty state with retry.

Status

Code-complete for the Android MVP. Home, Projects, GitHub, and Stack screens are fully functional. Settings and Project Detail screens are navigation-wired placeholders. Desktop module compiles and shares the same codebase but is treated as post-MVP.

Play Store submission is pending developer registration — not an engineering gap.

Project Doc

DevVault.md contains the full product spec, data models, API design, SQLDelight schema, caching strategy, build plan, and Play Store checklist.