Low Code Tool Opinions

Hello,

I'm looking for opinions on low code tools that people may have used, such as Appian, Mendix, Pega etc.

I have a project I've been working in my evenings on since lock down started (see link) and I'm after opinions on where existing tools fall down when it comes to supporting developers who work with them - or developers who have to integrate with solutions built using these tools.

I've made quite a few assumptions in my project so I'd like to make sure that these align with other developers opinions.

Personally, I've been working with Appian for a year or so on a client project and these are my major misgivings:

1. They rolled their own programming language, and its not nice

2. Their integrations to things like databases are very poor, and the integrations don't give you much in terms of automatic code provisioning

3. APIs defined within Appian cannot be made to follow any existing API design patterns

4. The interfaces are not accessible and are very heavy in terms of JS

5. Automated testing is nearly impossible due to the DOM generated by their UI rendering engine

Many thanks to anybody who takes the time to reply!