Captapi

API-as-a-Service that extracts transcripts, AI summaries, comments, engagement metrics, and channel analytics from YouTube, TikTok, Instagram, and Facebook videos.

Architecture

Backend: FastAPI (Python 3.12) — Apify scraping + OpenAI summarization
Frontend: Next.js 15 + Tailwind + shadcn/ui — landing, dashboard, billing
DB / Auth: Supabase (Postgres + Auth + Storage)
Cache / Rate limit: Upstash Redis
Scraping: Apify Actors
AI: OpenAI (gpt-4o-mini + Whisper)
Billing: Stripe (subscriptions + top-up credits)

Quick Start

Prerequisites

Python 3.12+
Node.js 20+
Supabase project (free tier)
Apify account + API token
OpenAI API key
Stripe account (test mode)
Upstash Redis (free tier)

1. Supabase Setup

# Install Supabase CLI
npm i -g supabase

# Login and link your project
supabase login
supabase link --project-ref YOUR_PROJECT_REF

# Push schema
supabase db push

2. Backend Setup

cd backend
cp .env.example .env
# Fill in env vars

# Install dependencies (using uv)
pip install uv
uv pip install -e .

# Run dev server
uvicorn app.main:app --reload --port 8000

3. Frontend Setup

cd frontend
cp .env.example .env.local
# Fill in env vars

npm install
npm run dev

Open http://localhost:3000.

Project Structure

socialkit-clone/
├── backend/                FastAPI service
│   ├── app/
│   │   ├── main.py         App entry
│   │   ├── core/           Config, auth, credits, security
│   │   ├── routers/        Endpoint handlers per platform
│   │   ├── services/       Apify, OpenAI, Supabase, Cache, Stripe
│   │   ├── schemas/        Pydantic models
│   │   └── utils/          Helpers
│   ├── pyproject.toml
│   └── Dockerfile
├── frontend/               Next.js 15 app
│   ├── app/                App Router
│   ├── components/         UI components
│   └── lib/                Supabase + API client
└── supabase/
    └── migrations/         SQL schema

API Endpoints

All endpoints require Authorization: Bearer capt_live_... header.

YouTube

GET /v1/youtube/transcript?url=...
GET /v1/youtube/summarize?url=...
GET /v1/youtube/video-details?url=...
GET /v1/youtube/comments?url=...&limit=...
GET /v1/youtube/channel-details?url=...
GET /v1/youtube/channel-videos?url=...&limit=...
GET /v1/youtube/playlist-videos?url=...&limit=...
GET /v1/youtube/search?q=...&limit=...
GET /v1/youtube/video-download?url=...

TikTok

GET /v1/tiktok/transcript|summarize|video-details|comments|channel-details|search|video-download

Instagram

GET /v1/instagram/transcript|summarize|details|comments|channel-details|channel-posts|channel-reels|reels-search|video-download

Facebook

GET /v1/facebook/transcript|summarize|details|comments|page-details

Video Files

POST /v1/video/transcript — multipart upload, Whisper transcription
POST /v1/video/summarize — transcription + AI summary

Account

GET /v1/account/usage — credit balance + recent requests
GET /v1/account/limits — plan + remaining quota

Pricing

| Plan | Price/mo | Credits/mo | $/Credit | |-----------|----------|-----------:|---------:| | Free | $0 | 100 lifetime | — | | Starter | $9 | 1,500 | $0.006 | | Pro | $29 | 6,000 | $0.0048 | | Business | $99 | 25,000 | $0.0039 | | Top-up | $5 | 500 | $0.01 |

License

MIT

captapi