The best alternatives to Composé are Flinto, AppStarter, and Rawson kit. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of Composé?
Tanka— Tanka = Slack + Glean, built for fast-growing startups.
BlueLibs is a collection of open source products designed to create the best possible experience for starting new projects, by offering rapid prototyping tools and a set of modules to fit the most demanding projects.