Streamlit makes it easy for you to visualize, mutate, and share data. The API reference is organized by activity type, like displaying data or optimizing performance. Each section includes methods associated with the activity type, including examples.
Protocol buffers are Google's language-neutral, platform-neutral, extensible mechanism for serializing structured data
Java Client SDK for Alpaca V2. Look at the section StockMarketDataWebsocket for Websocket API.
Client SDKs to connect to Alpaca V2 realtime (and historical?) stock trades
Alpaca v2 API - describes difference between SIP (2.5% of market volume) source and IEX (100%) source
API for real-time data. Historical data aPI is separate.