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What metrics library are people using with Clojure?
A quick Google search returned metrics and micrometer for Java/the JVM.
Anybody using these and can recommend them, or something else?
I like io.pedestal/pedestal.log
It is a bit undocumented.
I've been using riemann-clojure-client , which ships everything to Riemann , for several years. Not extensive like other libraries, but gives you a better control and with a few custom "with-timed-something" macros, it can measure practically anything. Also, don't forget that JVM (and other Java libraries, like Jetty) already comes with ready JMX metrics; you'd just need to pull them from the application. I use collectd  for that.