If you want to try the "normal" CLJS standard library in a playground, I now also updated the #cherry playground: (parse-long isn't added so it's part of the playground example, but I will add it in the next release) https://squint-cljs.github.io/cherry/?boilerplate=https%3A%2F%2Fgist.githubusercontent.com%2Fborkdude%2Fcf94b492d948f7f418aa81ba54f428ff%2Fraw%2Fa64b304b4025cceb1fefc0acd2812692a2dcdb9c%2Faoc_ui.cljs&src=OzsgSGVscGVyIGZ1bmN0aW9uczoKOzsgKGZldGNoLWlucHV0IHllYXIgZGF5KSAtIGdldCBBT0MgaW5wdXQKOzsgKGFwcGVuZCBzdHIpIC0gYXBwZW5kIHN0ciB0byBET00KOzsgKHNweSB4KSAtIGxvZyB4IHRvIGNvbnNvbGUgYW5kIHJldHVybiB4CgooZGVmIGlucHV0ICgtPj4gKGpzLWF3YWl0IChmZXRjaC1pbnB1dCAyMDIyIDEpKQogICAgICAgICAgICAgI19zcHkKICAgICAgICAgICAgIHN0ci9zcGxpdC1saW5lcwogICAgICAgICAgICAgKG1hcHYgcGFyc2UtbG9uZykpKQoKKGRlZm4gcGFydC0xCiAgW10KICAoLT4%2BIGlucHV0CiAgICAocGFydGl0aW9uLWJ5IG5pbD8pCiAgICAodGFrZS1udGggMikKICAgIChtYXAgIyhhcHBseSArICUpKQogICAgKGFwcGx5IG1heCkpKQoKKGRlZm4gcGFydC0yCiAgW10KICAoLT4%2BIGlucHV0CiAgICAocGFydGl0aW9uLWJ5IG5pbD8pCiAgICAodGFrZS1udGggMikKICAgIChtYXAgIyhhcHBseSArICUpKQogICAgKHNvcnQtYnkgLSkKICAgICh0YWtlIDMpCiAgICAoYXBwbHkgKykpKQoKKHRpbWUgKHBhcnQtMSkpCiNfKHRpbWUgKHBhcnQtMikp&repl=true You can easily switch between cherry and squint by renaming the /cherry/ to /squint/ part in the URL and vice versa!

^ Now also added parse-long and other 1.11 goodies to cherry, the above link should work and automatically use the newest version. Have a good Advent of Code!