These are Lua modules, not plugins. Most aren’t specifically related to Vera; but useful to any Lua programmer. There are (so far) string, time, XPath and JSON modules.
I suppose it rather depends on what you want to do… what you consider ‘useful’.
I have a bunch of functions loaded at startup for doing ‘utility’-like Luup things such as walking the luup.devices structure to look for (and exclude) certain classes of device. But herein lies the problem of reusable software… what I consider useful, you may not… what I like in a module, you may not… my data structures are not your data structures…
Sorry! Obviously hit a pessimistic streak just then.
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