Hi. First, which starter are you referring to and how are you building it (what command) ? What type of system or CI server is it ? Is the second run as slow ? That is indeed insanely very slow and I would like to get more details so I might better figure out what is going on.
We are currently working on two issues related to build time:
- Whitelisting packages to scan in Spring Boot apps triggers an extra
npm install: https://github.com/vaadin/spring/issues/489 - running Maven
cleancauses unnecessary deletion ofpackage.jsonhttps://github.com/vaadin/flow/issues/6151
Both of these are unfortunately hindering the build time, which is unbearably slow for some Spring Boot projects at the moment.
This is why we have recommended whitelisting the application packages for all Spring Boot apps: https://vaadin.com/docs/v14/flow/spring/tutorial-spring-configuration.html#special-configuration-parameters
But we have acknowledged that it is still not good enough, and thus we are currently planning further actions to improve the situation. We are looking at two things: the amount of things that are downloaded and making sure the frontend build (or any related scanning) is not triggered when it is not really needed. It should not take several minutes to start the application. There will be further details about these actions later on in our blog.