* Retool - https://retool.com (not OSS)
* OpenBlocks - https://github.com/openblocks-dev/openblocks
* Saltcorn - https://saltcorn.com/
* Interval - https://interval.com/
* Bracket - https://www.usebracket.com/
* Windmill - https://docs.windmill.dev/
* Budibase - https://budibase.com/
* AppSmith - https://www.appsmith.com/
* ToolJet - https://www.tooljet.com/
I only have direct experience with AppSmith.