I want to run a subprocess, and handle stdout and stderr differently. I came up with:

(defn run-handling-lines
  "Runs the command, passing each stdout/stderr line to the relevant handler.
   Returns the process exit code."
  [command handle-stdout handle-stderr]

  (let [proc (p/process command {:shutdown p/destroy-tree})
        reader->channel (fn [r]
                          (let [c (chan)]
                            (start-thread #(binding [*in* r]
                                             (loop [line (read-line)]
                                               (when (not (nil? line))
                                                 (>!! c line)
                                                 (recur (read-line))))
                                             (>!! c :exit)))
                            c))]

    (with-open [reader-stdout (io/reader (:out proc))
                reader-stderr (io/reader (:err proc))]
       (let [stdout-chan (reader->channel reader-stdout)
             stderr-chan (reader->channel reader-stderr)]
         (loop []
           (let [[line c] (alts!! [stdout-chan stderr-chan])
                 handler (condp = c
                           stdout-chan handle-stdout
                           stderr-chan handle-stderr)]
             (when (not= line :exit)
               (spy line)
               (handler line)
               (recur))))))
    (:exit @proc)))

Perhaps a naive question, but say I want to manage my static blog with netlify, using babashka. How does that work? Do I setup a script that downloads babashka from somewhere? Run the script locally and commit the results directly to git, letting Netlify just publish a pre-built site?