solidtime is an open-source time tracking application designed for freelancers and agencies. It provides a full-stack solution with a PHP backend (using a custom Laravel-like framework with strict typing) and a Vue 3 frontend served via Inertia.js. The system supports multi-tenant organizations with role-based permissions (Owner, Admin, Employee, Placeholder), project and task management, client and tag tracking, billable rates, goals, and detailed reporting with export to CSV, PDF, ODS, and XLSX. It also includes importers for Toggl, Clockify, Harvest, and generic CSV formats, as well as a native solidtime format. The architecture is a monolith with a RESTful API (versioned under /api/v1) and web controllers driven by Inertia.js. The backend uses a custom PHP framework that resembles Laravel but employs non-standard syntax (declare strict_types, use traits, fn closures). Key entry points include API controllers for time entries, projects, clients, tags, goals, reports, and import/export; console commands for administrative tasks, telemetry, and database consistency checks; and a Filament admin panel for CRUD operations. The frontend is built with Vue 3, Pinia stores, TanStack Query for caching, and a shared UI component library (packages/ui) that provides reusable primitives like dialogs, selects, calendars, and context menus. Data flows center around time entries, which are created via a timer or manual entry, associated with projects, tasks, clients, and tags, and aggregated for reporting and goal tracking. The system uses PostgreSQL as its primary database, with Redis for caching and queueing. External dependencies include a mail driver (Mailpit in dev), storage drivers (local/S3), and optional services like Gotenberg for PDF rendering and Paddle for subscriptions. The codebase is extensively tested with PHPUnit (unit/feature), Vitest (JS unit), and Playwright (E2E), and includes CI/CD pipelines for building, linting, and testing.