I just wish we had some stability. Ever tried writing for the browser in 2017? The toolchain keeps changing. We had jQuery, then React, then Angular. Building it required Grunt, then Gulp, SystemJS then Webpack. Modules went from AMD to UMD to CommonJS to something else. Package management moved from Bower to NPM to Yarn and back to NPM again.
Examples and quickstart projects which compiled perfectly six months ago no longer work because somewhere a package was upgraded. Answers on StackOverflow are irrelevant because they applied to version 1.3.5, and you're using version 2.7.1 now. Bugs on Github are left open, with not even a WONTFIX comment from the developers.
Not so long ago I remember a world where major tools were upgraded every 2-3 years. Windows XP was standard for over a decade. VB6 even longer. We had years to learn the quirks of IE6's "quirks mode". Nowadays if your Github project isn't on a six-week release cycle, it's abandonware.
I'd take a sabbatical if I could, but my skills would be worthless by the time I return.
All of the above problems are magnified on a CI system, because half the tools don't log to stderr or set the error code correctly.