Dataset Search - Making it easier to discover datasets. Made by Google.
Supabase - An open source Firebase alternative
Gigadata - Gigadata makes large datasets like total stock market prices, crypto, news, financials, reddit posts, government stats, the weather available via a simple API.
Unbounded - Serverless NoSQL database you query with JavaScript
Commons Marketplace - A marketplace to find and publish open data sets.
pREST - A fully RESTful API from any existing PostgreSQL database written in Go