Code from Zenika session for Clojure beginners ("NightClazz" session, 2013/12/05). This is just a backup, see repo https://github.com/nicokosi/clojure-nightclazz.

clojure-nightclazz.clj

(ns nightclazz.gameOfLife
  (:require [quil.core :as q]))

;; generation:
(def world (atom 
  #{[0 1] [1 2] [1 1] [1 3]}))

(defn setup []
  (q/smooth)
  (q/background 30))

(defn draw []
  (q/background (q/color 0 0 255))
  (q/stroke-weight 0)
  (q/fill (q/color 255 255 0))
  
  (doseq [[x y] (deref world)]
    (let [diam 20           
        x    (+ 100 (* x 20))
        y    (+ 100 (* y 20))]
    (q/ellipse x y diam diam))))

(q/defsketch example                  ;;Define a new sketch named example
  :title "game of life"  ;;Set the title of the sketch
  :setup setup                      ;;Specify the setup fn
  :draw draw                        ;;Specify the draw fn
  :size [323 200])                  ;;You struggle to beat the golden ratio

(swap! world step)

(defn neighbours 
  "calcule les 8 voisines" ; doc
  [[x y]]  
  {:post [(= (count %) 8)]} ; assertion sur le résultat
  (for [i (range (dec x) (+ x 2)) ;; for => produit cartésien
        j (range (dec y) (+ y 2))
        :when (not (and (= x i) (= y j)))] ; filtre la cellule courante
    [i j])
 )

(defn step [cells] ; fonction pure qu'on peut appeller en "explorant" dans le REPL
  ; ou pour connaitre la 1000 ème génération 
  (let [freqs (frequencies
                (mapcat neighbours @world) ; flatmap
                )]
    (set (keys (filter (fn [[cell n]]
           (if (contains? cells cell
                                 (<= 2 n 3)
                                 (= n 3))
                         
    )
 ) freqs)))))

(while true?(swap! world step)
  (Thread/sleep 100))

project.clj

(defproject clojure-nightclazz "0.1.0-SNAPSHOT"
  :description "Code from Zenika session for Clojure beginners (\"NightClazz\" session, 2013/12/05)."
  :url "https://github.com/nicokosi/clojure-nightclazz"
  :dependencies [
                 [org.clojure/clojure "1.5.1"]
                 [quil "1.6.0"]
                 
                 ;; deuxième session
                 [ring "1.2.1"]])

web.clj

(ns web
  (:require [ring.adapter.jetty :as jetty]
    [ring.middleware.params :as params]
    [clojure.edn :as edn]
    [core :as core]))

;;(defonce lineages (atom []))
(defonce lineages (atom [[0 0] [1 1] [0 1] [1 0]]))

(def create-gen 
  (params/wrap-params
    (fn [req]
      (let [cells (-> req :params (get "cells") edn/read-string)
            lineage (iterate core/step cells)
            lineages (swap! lineages conj lineage)
            n (dec (count lineages))]
        {:status 201
         :headers {"Location" (str "/" n "/0")}}))))

(defn app [req]
  (let [uri (:uri req)]
    (if (= "/create" uri)
      (create-gen req)
      (or 
        (when-let [[_ id n] (re-matches #"/(\d+)/(\d+)" uri)]
          (let [id (Long/parseLong id)
                n (Long/parseLong n)]
            (when-let [cells (some-> @lineages (nth id) (nth n))]
              {:status 200
               :headers {"Content-Type" "text/plain"}
               :body (str (pr-str {:cells cells :next (str "/" id "/" (inc n))}))})))
        {:status 404
         :headers {"Content-Type" "text/plain"}
         :body "Pas trouvé"}))))

(defonce server (jetty/run-jetty #'app
                  {:port 8080
                   :join? false}))