takes the same arguments as spec/keys and returns a regex op that matches sequences of key/values, converts them into a map, and conforms that map with a corresponding spec/keys call: user=> (s/conform (s/keys :req-un [::a ::c]) {:a 1 :c 2}) {:a 1, :c 2} user=> (s/conform (s/keys* :req-un [::a ::c]) [:a 1 :c 2]) {:a 1, :c 2} the resulting regex op can be composed into a larger regex: user=> (s/conform (s/cat :i1 integer? :m (s/keys* :req-un [::a ::c]) :i2 integer?) [42 :a 1 :c 2 :d 4 99]) {:i1 42, :m {:a 1, :c 2, :d 4}, :i2 99}