Web & Mobile Development

Ledgerin is a personal finance mobile app built with an offline-first approach using SQLite via Drift as the primary local database. All transactions are stored locally — the app runs fully without internet. A Go + Swagger backend handles server synchronization, and Google Drive API is used for independent data backup. Released to Google Play Store and Firebase App Distribution.

📊 Impact

• Offline-first: app runs fully without internet — data always available
• SQLite via Drift as local single source of truth — high performance with no network latency
• Google Drive API for independent financial data backup & restore
• Go + Swagger backend for server sync with contract-first API design
• Built using vibe coding approach — from idea to Play Store in a short timeframe

🧩 Tech Stack

Flutter, Dart, Drift (SQLite), Go (Golang), Swagger / OpenAPI, Google Drive API, Firebase Auth, REST API, Google Play Store

⚡ Problem Statement

• Finance apps dependent on internet cannot be used with poor or no connection
• Financial data must always be instantly available without waiting for server responses
• Independent backup needed — users don't want to fully depend on a single cloud vendor
• Backend API must be documented for long-term maintainability
• Fast development needed since this is a personal project outside work hours

🧠 Solution Overview

• Drift (SQLite) as primary local database — all CRUD operations run locally without network calls
• Offline-first architecture: UI always reads from local DB, server sync happens in background when online
• Firebase Auth for authentication — only the auth layer requires connection on first login
• Google Drive API for backup & restore: users can export/import data to their own Google Drive
• Go REST API for data sync — Swagger spec defined before implementation (contract-first)
• Vibe coding: AI-assisted scaffolding and UI iteration for faster delivery

🏗️ Architecture

1. Local DB Layer: Drift (SQLite) — type-safe ORM for Flutter, single source of truth, zero network dependency
2. Auth Layer: Firebase Authentication — Google Sign-In, only required on first login
3. Sync Layer: Go REST API — syncs local data to server when connection is available
4. Backup Layer: Google Drive API — export/import SQLite data dump to user's Google Drive
5. API Contract: Swagger/OpenAPI — contract-first, spec written before Go implementation
6. Deployment: Google Play Store (production) + Firebase App Distribution (beta)

🔥 Challenges & Solutions

• Conflict resolution during sync — local data can change while offline, requiring a merge strategy when back online
• Drift schema migration — SQLite schema changes require careful migrations to avoid losing existing data
• Google Drive OAuth flow in Flutter — token handling across sessions requires careful management

Home Tracker is a household management mobile app with an offline-first architecture using SQLite via Drift as the primary local database. Data is stored locally so the app runs without internet. Firestore is used as a pull & sync layer to synchronize data across devices within a household — not as the primary database. A Go + Swagger backend handles server-side logic. Released to the Google Play Store.

📊 Impact

• Offline-first: app runs fully without internet — household data always available
• Drift (SQLite) as local source of truth — instant performance with no network latency
• Firestore as sync layer: pull & sync across devices within one household when online
• Shared household data — household members see the same updates after sync
• Built using vibe coding approach — fast delivery as a personal project

🧩 Tech Stack

Flutter, Dart, Drift (SQLite), Firebase (Auth, Firestore), Go (Golang), Swagger / OpenAPI, REST API, Google Play Store

⚡ Problem Statement

• Household management was manual — shopping lists and tasks scattered across chats and paper
• Household members need the same data but are not always connected to internet simultaneously
• App must work offline — core functions must not depend on connection
• Cross-device sync must be smooth without confusing conflicts for users

🧠 Solution Overview

• Drift (SQLite) as primary local database — all operations run locally, offline by default
• Firestore as pull & sync layer — not a real-time listener, but periodic pull when connection available
• Sync strategy: local changes are queued, pushed to Firestore when online, other devices pull on app open
• Firebase Auth for user identity — ensures data syncs to the correct household
• Go REST API for server-side business logic with Swagger documentation
• Vibe coding: AI-assisted development for rapid iteration from concept to product

🏗️ Architecture

1. Local DB Layer: Drift (SQLite) — type-safe ORM, primary data store, zero network dependency for daily operations
2. Auth Layer: Firebase Authentication — user identity for routing sync to the correct household
3. Sync Layer: Firestore (pull & sync) — not a real-time listener; data pulled on app open or manual refresh
4. Conflict Strategy: last-write-wins with timestamp — simple and effective for household use case
5. Backend Layer: Go REST API — server-side logic and orchestration with Swagger-documented endpoints
6. Deployment: Google Play Store

🔥 Challenges & Solutions

• Designing a sync strategy that isn't confusing — last-write-wins chosen for its simplicity and sufficiency for household use
• Drift schema migration — local schema updates require safe migrations to avoid corrupting existing data
• Separating concerns between local DB and Firestore sync layer — both must be loosely coupled for flexibility