$ mvn clean install -Dmaven.repo.local=/home/jeremy/.m2/repository1 -DskipTests=true -P maximum

Am I wrong in thinking that resulting TP in my "repository1" is to be used when building & testing my components with the mvn clean install command and specifying -Dmaven.repo.local=/home/jeremy/.m2/repository1 ?

Further builds won't use the Target Platfrom in repository1. I don't think you gain anything with this approach compared to the default one which is to consume it from Nexus.

A target-platform contains reference to some site. Those site are used *at build-time* by your components build to resolve the dependencies.
The caching in Tycho does not work the same way as caching in Maven. Building the target-platform locally is not enough to save some time. Moreover, Tycho adds dependencies to its cache when you run a "normal" build of your component. Trying to pre-fill cache won't make you save time, it will even take more time as it will try to fetch stuff that may not be useful to you.

In a nutshell, running a local build of TP as you describe here is useless.

If you want to save some time, then you can have a look in the jbosstools/multiple/multiple.target.repo folder. Here is a mirror site of the target platfrom. You can then define it as a mirror of the unified site in your settings.xml: http://wiki.eclipse.org/Tycho/Target_Platform/Authentication_and_Mirrors . But this will require you to maintain the mapping between TP version and local site in your settings.xml. That can be a source of errors.

How much time does it take to make a build on your machine?
I'm expected that setting up Akamai ( https://issues.jboss.org/browse/JBIDE-13283 ) will speed up most downloads from download.jboss.org/tools so you won't have to deal with some much error-prone workflows to save some build time.

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Mickael Istria
Eclipse developer at JBoss, by Red Hat
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