OpenStonks

Real-time stock price ingestion into a TimescaleDB time-series database. Fetches live prices from multiple market data sources and keeps both a current snapshot and full price history per symbol.

Architecture

YFinance Service ─┐
Polygon API       ├──► Go Ingester ──► PostgreSQL + TimescaleDB
Alpaca API        │
Finnhub API      ─┘

The Go ingester polls all configured sources on a set interval, upserts the latest price per symbol into live_prices, and appends to price_history only when the price actually changes.

Stack

Component	Technology
Ingestion service	Go 1.25
Time-series database	PostgreSQL 16 + TimescaleDB
YFinance adapter	Python (FastAPI)
Containerization	Docker + Docker Compose

Prerequisites

• Docker and Docker Compose
• (Optional) API keys for Polygon, Alpaca, or Finnhub

Quickstart

# Production
make build

# Development (with live reload)
make dev

Both commands start the full stack: TimescaleDB, the YFinance microservice, and the Go ingester.

Configuration

Set environment variables in your shell or a .env file before running. Only SYMBOLS and UPDATE_INTERVAL are required — API keys are optional and enable additional data sources.

Variable	Default	Description
SYMBOLS	69 major stocks	Comma-separated list of ticker symbols to track
UPDATE_INTERVAL	1s	How often to fetch prices (Go duration string)
POLYGON_API_KEY	—	Enables Polygon.io source
ALPACA_API_KEY	—	Enables Alpaca source
ALPACA_API_SECRET	—	Required with ALPACA_API_KEY
FINNHUB_API_KEY	—	Enables Finnhub source

Connecting to the Database

The database is exposed on localhost:5432 with these credentials:

Field	Value
Host	localhost
Port	5432
Database	openstonks
Username	openstonks
Password	openstonks

Connection string:

postgres://openstonks:openstonks@localhost:5432/openstonks?sslmode=disable

Database Schema

live_prices — latest price per symbol (upserted on each fetch)

Column	Type	Notes
symbol	text	PRIMARY KEY
price	numeric
updated_at	timestamptz	Only updated when timestamp is newer
source	text	Which data source provided the price

price_history — full audit trail (TimescaleDB hypertable, partitioned by time)

Column	Type	Notes
time	timestamptz	Partition key
symbol	text
price	numeric	Only recorded when price actually changes
source	text