I started using Perl again. It is a well-defined language with a good library system that's also been around long enough to have stabilized. The fact that it is so integrated into many system things help ensure that it remains stable. It's flexible, but you can still write readable code with it.
The only thing I couldn't find at first was a good editor for it. I would up with ... IntelliJ. The only minor thing that Community Edition doesn't have is editing CSS, and I can live without it. There's a Perl plugin that does good completion and navigation (Find Uses / Find Definition, semi-intelligent completion).
I tried the IntelliJ plugin and unfortunately just couldn't make it work. Past a certain point of metaprogramming (e.g. using complicated-but-not-objectively-that-weird Moose constructions with multiple levels of subclassing and mixin-based inheritance), it just couldn't keep up and started providing autocomplete suggestions that were completely off-base.
The only thing I couldn't find at first was a good editor for it. I would up with ... IntelliJ. The only minor thing that Community Edition doesn't have is editing CSS, and I can live without it. There's a Perl plugin that does good completion and navigation (Find Uses / Find Definition, semi-intelligent completion).
And that's what I am using now for prototyping.