[ANN] e3 - major architectural update

[Anders Lindh Olsson via Tech-talk <tech-talk at aps.anl.gov>]

Hi all,

It is my pleasure and privilege to announce the next generation of e3 (https://e3.pages.ess.eu), the EPICS environment used at ESS.

A major architectural change is that e3 now uses conda as its package and environment manager, modelled on conda-forge. This gives us distro-agnostic deployment, full reproducibility via stored build artifacts, and fully resolved dependencies across build/run/test. It also moves us away from the traditional model of shared installations distributed over NFS. As before, e3 supports isolated environments - meaning multiple IOCs with different module versions, or different EPICS base versions, can coexist on the same host. This, together with distribution agnosticism, allows us to migrate away from the EOL CentOS 7.

Alongside this, we have released require 6.0.0, which sheds a lot of its former complexity now that a proper package manager is in the picture. Notably, module loading is now delegated to the dynamic linker (ld) rather than handled internally. Features that are now the package manager's job - multi-version handling, dependency resolution - have been removed. We have also switched to PVXS as the IOC PVA stack (softIocPVX).

Questions and discussion welcome here or in the "EPICS e3" room on EPICS Chat.

Cheers,

Anders on behalf of the e3 team