Some feedback: • you don't have to repeat :require, use just one (https://github.com/bbatsov/clojure-style-guide#sort-requirements-and-imports) • strange indentation (for example in make-url - function body belongs right under the argument vector, but you have there some additional space) (https://github.com/bbatsov/clojure-style-guide#optional-new-line-after-fn-name) • in data->singular, you could use -> to avoid nesting and destructuring instead of let • you could rewrite is-value? with and:

(defn is-value?
  "Returns true when :value starts with a digit in maps `m` from [[map-rows]]."
  [{:keys [value]}]
  (and (string? value)
       (Character/isDigit ^char (first value))))

@U0596F9G4DT check out the (quiet) #C064BA6G2 and (casual) #CBJ5CGE0G channels.

Thank you both! 😄 @U01RL1YV4P7 @U04V70XH6