Integration Connectors
OpenInt
Open-source embeddable product integrations.  
Vessel
Developer-first, native integration platform for GTM tools
YepCode
All-in-one platform to connect APIs and services in a serverless environment. It brings all the agility and benefits of NoCode tools but with all the power of using programming languages. The free tier includes 1.000 yeps
Apideck
Integration marketplace builder, one-API with 3rd parties for quick development
Sequin
Interface with third-party services using SQL. 
Nango
Hundreds of pre-built product integrations with 250+ APIs, customizable in code. 
Revert
Open-source unified API to build B2B product integrations. 
Panora
Easy, flexible API to add customer-facing integrations to your SaaS product. 