diff --git a/src/main/lemondronor/advisorycircular.cljs b/src/main/lemondronor/advisorycircular.cljs
index 464a839..00c253b 100644
--- a/src/main/lemondronor/advisorycircular.cljs
+++ b/src/main/lemondronor/advisorycircular.cljs
@@ -267,21 +267,46 @@
       v)))
 
 
+(defn nearby-airports
+  ([config lat lon]
+   (nearby-airports config lat lon {}))
+  ([config lat lon options]
+   (p/let [radius (or (:radius options) 7)
+           results (pelias/nearby (:pelias config)
+                                  lat lon
+                                  {:categories "transport:air:aerodrome"
+                                   :boundary.circle.radius radius})
+           blocklist (get-in config [:airport :blocklist] [])
+           blocklist-patterns (map #(re-pattern (str "(?i)" %)) blocklist)]
+     (->> (:features results)
+          (remove (fn [airport] (some #(re-find % (get-in airport [:properties :label]))
+                                      blocklist-patterns)))))))
+
+
 (defn closest-airport [config lat lon]
-  (p/let [results (pelias/nearby (:pelias config)
-                                 lat lon
-                                 {:categories "transport:air:aerodrome"
-                                  :boundary.circle.radius 7})
-          blocklist (get-in config [:airport :blocklist] [])
-          blocklist-patterns (map #(re-pattern (str "(?i)" %)) blocklist)
-          _ (println blocklist-patterns)]
-    (->> (:features results)
-         (remove (fn [airport] (some #(re-find % (get-in airport [:properties :label]))
-                                     blocklist-patterns)))
+  (p/let [airports (nearby-airports config lat lon)]
+    (->> airports
          (sort-by #(get-in % [:properties :distance]))
          first)))
 
 
+(defn airport-geojson [config]
+  (p/let [airport->feature (fn [a]
+                             (let [props (:properties a)]
+                               {:type "Feature"
+                                :properties {:shape "Circle"
+                                             :radius (* 1000 (:minimum-airport-distance-km config))
+                                             :name (:label props)}
+                                :geometry {:type "Point"
+                                           :coordinates (-> a :geometry :coordinates)}}))
+          lat (:lat config)
+          lon (:lon config)
+          airports (nearby-airports config lat lon {:radius (+ (:radius-km config)
+                                                               (:minimum-airport-distance-km config))})]
+    {:type "FeatureCollection"
+     :features (map airport->feature airports)}))
+
+
 (defn log-table [table keys]
   (let [s (with-out-str (pprint/print-table keys table))
         lines (string/split-lines s)]
@@ -638,12 +663,11 @@
       (.option "--secrets <path>" "Path to the secrets yaml file" "secrets.yaml")
       (.option "--history <path>" "Path to history/state file" "advisorycircular.json")
       (.option "--log-prefix <prefix>" "Log prefix to use")
+      (.option "--airport-geojson" "Generate airport GEOJSON and exit")
       (.parse (.-argv js/process)))
   (logging/set-log-prefix! (or (.-logPrefix commander) ""))
   (reset! log-prefix (or (.-logPrefix commander) ""))
-  (let [start-time (current-time)]
-    ;; If --config-path is specified, definitely try to read that
-    ;; file. Otherwise, only read config.yaml if it exists.
+  (if (.-airportGeojson commander)
     (p/try
       (p/let [base-config (if-let [config-path (.-config commander)]
                             (util/read-config config-path)
@@ -651,45 +675,63 @@
                               (util/read-config default-config-path)
                               {}))
               cli-config (build-config-from-commander commander)
-              secrets (util/read-config (.-secrets commander))
-              config (build-config base-config cli-config secrets)
-              _ (validate-config config)
-              history-db-path (:history-db-path config)
-              _ (when (not (fs/existsSync history-db-path))
-                  (log-info "%s does not exist; creating empty one." history-db-path)
-                  (write-history-db {} history-db-path))
-              db (read-history-db history-db-path)
-              data (get-adsbexchange-live-data
-                    (merge (:adsbx config)
-                     {:lat (:lat config)
-                      :lon (:lon config)
-                      :radius-nm (* (:radius-km config) 0.539957)}))
-              now (current-time)
-              [new-db potential-circles] (-> db
-                                             (update-history-db (:aircraft data) now config)
-                                             (detect-circles now config))]
-        (p/do
-          (when potential-circles
-            (doseq [ac potential-circles]
-              (log-warn "%s: New circle detected: %s" (:icao ac) (ac-desc ac)))
-            (process-potential-circles potential-circles config now))
-          (write-history-db new-db (:history-db-path config))
-          (let [end-time (current-time)]
-            (log-info
-             "Finished in %f s: %s aircraft; %s circles; top curvinesses: %s"
-             (/ (- end-time start-time) 1000)
-             (count new-db)
-             (count potential-circles)
-             (->> (vals new-db)
-                  (sort-by :curviness)
-                  reverse
-                  (take 3)
-                  (map #(str (:icao %) ":" (.toFixed (:curviness %) 0)))
-                  (string/join " "))))))
+              config (build-config base-config cli-config {})
+              geojson (airport-geojson config)]
+        (println (.stringify js/JSON (clj->js geojson) nil "  ")))
       (p/catch :default e
         (log-error "%s" e)
         (log-error "%s" (.-stack e))
-        (.exit js/process 1)))))
+        (.exit js/process 1)))
+    (let [start-time (current-time)]
+      ;; If --config-path is specified, definitely try to read that
+      ;; file. Otherwise, only read config.yaml if it exists.
+      (p/try
+        (println "OMG DOING THIS")
+        (p/let [base-config (if-let [config-path (.-config commander)]
+                              (util/read-config config-path)
+                              (if (fs/existsSync default-config-path)
+                                (util/read-config default-config-path)
+                                {}))
+                cli-config (build-config-from-commander commander)
+                secrets (util/read-config (.-secrets commander))
+                config (build-config base-config cli-config secrets)
+                _ (validate-config config)
+                history-db-path (:history-db-path config)
+                _ (when (not (fs/existsSync history-db-path))
+                    (log-info "%s does not exist; creating empty one." history-db-path)
+                    (write-history-db {} history-db-path))
+                db (read-history-db history-db-path)
+                data (get-adsbexchange-live-data
+                      (merge (:adsbx config)
+                             {:lat (:lat config)
+                              :lon (:lon config)
+                              :radius-nm (* (:radius-km config) 0.539957)}))
+                now (current-time)
+                [new-db potential-circles] (-> db
+                                               (update-history-db (:aircraft data) now config)
+                                               (detect-circles now config))]
+          (p/do
+            (when potential-circles
+              (doseq [ac potential-circles]
+                (log-warn "%s: New circle detected: %s" (:icao ac) (ac-desc ac)))
+              (process-potential-circles potential-circles config now))
+            (write-history-db new-db (:history-db-path config))
+            (let [end-time (current-time)]
+              (log-info
+               "Finished in %f s: %s aircraft; %s circles; top curvinesses: %s"
+               (/ (- end-time start-time) 1000)
+               (count new-db)
+               (count potential-circles)
+               (->> (vals new-db)
+                    (sort-by :curviness)
+                    reverse
+                    (take 3)
+                    (map #(str (:icao %) ":" (.toFixed (:curviness %) 0)))
+                    (string/join " "))))))
+        (p/catch :default e
+          (log-error "%s" e)
+          (log-error "%s" (.-stack e))
+          (.exit js/process 1))))))
 
 
 ;; (.on js/process "unhandledRejection"