> ## Documentation Index
> Fetch the complete documentation index at: https://sportsindex.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Tech Stack

> Technologies powering the Sports Index platform

## Backend

| Technology             | Purpose                                    |
| ---------------------- | ------------------------------------------ |
| **Python 3.13**        | Primary language                           |
| **FastAPI**            | Web framework and API routing              |
| **SQLAlchemy**         | ORM and database models                    |
| **PostgreSQL**         | Primary database                           |
| **pgvector**           | Semantic embeddings and similarity search  |
| **SendGrid**           | Transactional email delivery               |
| **OpenAI**             | Text embeddings (`text-embedding-3-small`) |
| **S3 / Cloudflare R2** | Media file storage                         |
| **Pillow**             | Image optimization and processing          |
| **FFmpeg**             | GIF-to-video conversion                    |

## Frontend

| Technology                | Purpose                                  |
| ------------------------- | ---------------------------------------- |
| **Vanilla JavaScript**    | No framework — lightweight, fast loading |
| **Jinja2**                | Server-side HTML templating              |
| **CSS Custom Properties** | Theming and dark mode                    |
| **ES6 Modules**           | Component architecture for editors       |

## Infrastructure

| Technology   | Purpose                |
| ------------ | ---------------------- |
| **Railway**  | Hosting and deployment |
| **Docker**   | Containerization       |
| **Mintlify** | Documentation site     |

## Architecture Overview

Sports Index follows a layered architecture:

```
Frontend (Vanilla JS + Jinja2 Templates)
    ↓ HTTP/JSON
Routes / API Layer (FastAPI, ~120 endpoints)
    ↓ Function calls
Service Layer (8 services + 7 post type handlers)
    ↓ Function calls
Data Access Layer (28 repository singletons)
    ↓ ORM/SQL
PostgreSQL + pgvector
```

### Key Patterns

* **Post Type Handlers**: Abstract base class pattern for 7 content types (external\_media, chart, data\_table, uploaded\_media, timeline, page, collection)
* **Canonical Deduplication**: External URLs stored once globally, users link via relationships
* **Dual Tagging**: Owned posts use `content_post_tags`, canonical posts use `topic_post_index`
* **Denormalized Caches**: `TopicPostIndex`, `TopicTimelineCache`, `UserLibraryCache` for fast reads
* **Feature-Flagged Embeddings**: Semantic search gated behind `EMBEDDING_ENABLED`