diff --git a/.gitignore b/.gitignore
index c7535bc..b10f8ad 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,3 +14,5 @@ pom.xml.asc
 /.idea
 .hgignore
 .hg/
+/.lsp/
+/.clj-kondo/
diff --git a/src/main/shadow/css.clj b/src/main/shadow/css.clj
index 3c611ab..5a984b6 100644
--- a/src/main/shadow/css.clj
+++ b/src/main/shadow/css.clj
@@ -37,7 +37,7 @@
         ;; but may end up emitting invalid references in code
         ;; which again is fine in JS since it'll just be undefined
         css-id
-        (s/generate-id ns-str line column)
+        (s/generate-id (vec body))
 
         passthrough
         (->> body
diff --git a/src/main/shadow/css/build.cljc b/src/main/shadow/css/build.cljc
index 1f0b108..75f5052 100644
--- a/src/main/shadow/css/build.cljc
+++ b/src/main/shadow/css/build.cljc
@@ -91,11 +91,18 @@
       (emitln w "  " (name prop) ": " (get group-rules prop) ";"))
     (emitln w "}")))
 
-(defn emit-def [w {:keys [sel rules at-rules ns line column rules] :as def}]
-  ;; (emitln w (str "/* " ns " " line ":" column " */"))
+(defn emit-meta-comments
+  "Within a single comment, output a list of namespaces, line and column numbers
+  for a given set of rules."
+  [w rules]
+  (emitln w (str "/*\n"
+                 (str/join "\n"
+                           (for [{:keys [ns line column]} rules]
+                             (str ns " " line ":" column )))
+                 "\n*/")))
 
+(defn emit-def [w {:keys [sel rules at-rules ns line column rules] :as def}]
   (emit-rule w sel rules)
-
   (doseq [[media-query rules] at-rules]
     (emitln w media-query "{")
     (emit-rule w sel rules)
@@ -114,8 +121,12 @@
               [(doseq [inc classpath-includes]
                  (emitln sw (slurp (io/resource inc))))])
 
-          (doseq [def rules]
-            (emit-def sw def))
+          (doseq [[_ def-rules] (group-by :css-id rules)]
+            ;; emit comments for all of the rules
+            (emit-meta-comments sw def-rules)
+            ;; but we only need to emit the first actual def
+            (emit-def sw (first def-rules)))
+
           (.toString sw))))))
 
 (defn collect-namespaces-for-chunk
@@ -187,8 +198,8 @@
       (let [all-rules
             (->> (for [ns (:chunk-namespaces chunk)
                        :let [{:keys [ns css] :as ns-info} (get namespaces ns)]
-                       {:keys [line column] :as form-info} css
-                       :let [css-id (s/generate-id ns line column)]]
+                       {:keys [form] :as form-info} css
+                       :let [css-id (s/generate-id form)]]
                    (-> (ana/process-form build-state form-info)
                        (assoc
                          :ns ns
@@ -499,4 +510,4 @@
               (load-colors-from-classpath)
               (load-indexes-from-classpath)
               (generate-color-aliases)
-              (generate-spacing-aliases))))))
\ No newline at end of file
+              (generate-spacing-aliases))))))
diff --git a/src/main/shadow/css/specs.cljc b/src/main/shadow/css/specs.cljc
index 520ef5f..fa1c5c1 100644
--- a/src/main/shadow/css/specs.cljc
+++ b/src/main/shadow/css/specs.cljc
@@ -1,6 +1,7 @@
 (ns shadow.css.specs
   (:require [clojure.spec.alpha :as s]
-            [clojure.string :as str]))
+            [clojure.string :as str]
+            [clojure.walk :refer [postwalk]]))
 
 (s/def ::alias keyword?)
 
@@ -94,11 +95,21 @@
       {:parts [] :invalid true :body body :spec (s/explain-data ::class-def body)}
       conformed)))
 
-(defn generate-id [ns line column]
-  (str (-> (str ns)
-           (str/replace #"\." "_")
-           (munge))
-       "__"
-       "L" line
-       "_"
-       "C" column))
\ No newline at end of file
+(defn generate-id
+  "Generates a class name which is unique given the contents. Will account for
+  different ordering within the subqueries."
+  [rules]
+  (str "sc-" (postwalk
+              (fn [rule]
+                (cond
+                  ;; postwalk will give you a vector pair for a map before it
+                  ;; gives you the actual map
+                  (map-entry? rule)
+                  rule
+
+                  (vector? rule)
+                  (hash (sort rule))
+
+                  :else
+                  (hash rule)))
+              rules)))
diff --git a/src/test/shadow/css/specs_test.cljc b/src/test/shadow/css/specs_test.cljc
new file mode 100644
index 0000000..68d601d
--- /dev/null
+++ b/src/test/shadow/css/specs_test.cljc
@@ -0,0 +1,33 @@
+(ns shadow.css.specs-test
+  (:require
+   [clojure.test :refer [deftest is testing]]
+   [shadow.css.specs :as specs]))
+
+(deftest generate-id-test
+  (testing "Complex ID"
+    (is (= "sc--1789522625"
+           (specs/generate-id [:px-4 :my-2
+                               "pass"
+                               :c-text-1
+                               [:&hover :py-10]
+                               [:md+ :px-6
+                                ["@media print" :px-2]]
+                               [:lg+ :px-8
+                                [:&hover :py-12]]]))))
+
+  (testing "Order of rules"
+    (testing "doesn't matter within selectors/main list"
+      (is (= (specs/generate-id [:px-4 :my-2
+                                 [:&hover :m-4 :py-10 :px-4]
+                                 [:lg+ :px-8
+                                  [:&hover :p-4 :py-12]]])
+             (specs/generate-id [:px-4 :my-2
+                                 [:&hover :py-10 :m-4 :px-4]
+                                 [:lg+ :px-8
+                                  [:&hover :py-12 :p-4]]]))))
+
+    (testing "does matter for the whole structure"
+      (is (not= (specs/generate-id [:m-4
+                                    [:&hover :px-4]])
+                (specs/generate-id [:px-4
+                                    [:&hover :m-4]]))))))