diff --git a/test/monger/test/querying.clj b/test/monger/test/querying.clj
index ec431e0..143c6c9 100644
--- a/test/monger/test/querying.clj
+++ b/test/monger/test/querying.clj
@@ -22,9 +22,11 @@
 
 
 ;;
-;; by ObjectId
+;; monger.collection/* finders ("low-level API")
 ;;
 
+;; by ObjectId
+
 (deftest query-full-document-by-object-id
   (let [coll "docs"
         oid  (ObjectId.)
@@ -34,11 +36,9 @@
     (is (= doc (mgcol/find-one-as-map coll { :_id oid })))))
 
 
-;;
 ;; exact match over string field
-;;
 
-(deftest query-full-document-using-exact-matching-over-string-field
+(deftest query-full-document-with-find-maps-using-exact-matching-over-string-field
   (let [coll "docs"
         doc  { :title "monger" :language "Clojure" :_id (ObjectId.) }]
     (mgcol/insert coll doc)
@@ -46,11 +46,9 @@
     (is (= doc (from-db-object (first (mgcol/find coll { :title "monger" })) true)))))
 
 
-;;
 ;; exact match over string field with limit
-;;
 
-(deftest query-full-document-using-exact-matching-over-string-field-with-limit
+(deftest query-full-document-with-find-maps-using-exact-matching-over-string-with-field-with-limit
   (let [coll "docs"
         doc1  { :title "monger"  :language "Clojure" :_id (ObjectId.) }
         doc2  { :title "langohr" :language "Clojure" :_id (ObjectId.) }
@@ -61,7 +59,7 @@
     (is (= [doc1] result))))
 
 
-(deftest query-full-document-using-exact-matching-over-string-field-with-limit-and-offset
+(deftest query-full-document-with-find-maps-using-exact-matching-over-string-field-with-limit-and-offset
   (let [coll "docs"
         doc1  { :title "lucene"    :language "Java" :_id (ObjectId.) }
         doc2  { :title "joda-time" :language "Java" :_id (ObjectId.) }
@@ -73,4 +71,79 @@
                                            (to-db-object { :title 1 })))
                                true)]
     (is (= 2 (count result)))
-    (is (= [doc1 doc3] result))))
\ No newline at end of file
+    (is (= [doc1 doc3] result))))
+
+
+;; < ($lt), <= ($lte), > ($gt), >= ($gte)
+
+(deftest query-with-find-maps-using-$lt-operator
+  (let [coll "docs"
+        doc1 { :language "Clojure" :_id (ObjectId.) :inception_year 2006 }
+        doc2 { :language "Java"    :_id (ObjectId.) :inception_year 1992 }
+        doc3 { :language "Scala"   :_id (ObjectId.) :inception_year 2003 }
+        _      (mgcol/insert-batch coll [doc1 doc2])
+        lt-result  (mgcol/find-maps coll { :inception_year { "$lt"  2000 } })
+        lte-result (mgcol/find-maps coll { :inception_year { "$lte" 1992 } })
+        gt-result  (mgcol/find-maps coll { :inception_year { "$gt"  2005 } })
+        gte-result (mgcol/find-maps coll { :inception_year { "$gte" 2006 } })]
+    (is (= [doc2] lt-result))
+    (is (= [doc2] lte-result))
+    (is (= [doc1] gt-result))
+    (is (= [doc1] gte-result))))
+
+
+;; $all
+
+(deftest query-with-find-maps-using-$all
+  (let [coll "docs"
+        doc1 { :_id (ObjectId.) :title "Clojure" :tags ["functional" "homoiconic" "syntax-oriented" "dsls" "concurrency features" "jvm"] }
+        doc2 { :_id (ObjectId.) :title "Java"    :tags ["object-oriented" "jvm"] }
+        doc3 { :_id (ObjectId.) :title "Scala"   :tags ["functional" "object-oriented" "dsls" "concurrency features" "jvm"] }
+        -    (mgcol/insert-batch coll [doc1 doc2 doc3])
+        result1 (mgcol/find-maps coll { :tags { "$all" ["functional" "jvm" "homoiconic"] } })
+        result2 (mgcol/find-maps coll { :tags { "$all" ["functional" "native" "homoiconic"] } })
+        result3 (mgcol/find-maps coll { :tags { "$all" ["functional" "jvm" "dsls"] } })]
+    (is (= [doc1] result1))
+    (is (empty? result2))
+    (is (= 2 (count result3)))))
+
+
+;; $exists
+
+(deftest query-with-find-one-as-map-using-$exists
+  (let [coll "docs"
+        doc1 { :_id (ObjectId.) :published-by "Jill The Blogger" :draft false :title "X announces another Y" }
+        doc2 { :_id (ObjectId.) :draft true :title "Z announces a Y competitor" }
+        _    (mgcol/insert-batch coll [doc1 doc2])
+        result1 (mgcol/find-one-as-map coll { :published-by { "$exists" true } })
+        result2 (mgcol/find-one-as-map coll { :published-by { "$exists" false } })]
+    (is (= doc1 result1))
+    (is (= doc2 result2))))
+
+;; $mod
+
+(deftest query-with-find-one-as-map-using-$mod
+  (let [coll "docs"
+        doc1 { :_id (ObjectId.) :counter 25 }
+        doc2 { :_id (ObjectId.) :counter 32 }
+        doc3 { :_id (ObjectId.) :counter 63 }
+        _    (mgcol/insert-batch coll [doc1 doc2 doc3])
+        result1 (mgcol/find-one-as-map coll { :counter { "$mod" [10, 5] } })
+        result2 (mgcol/find-one-as-map coll { :counter { "$mod" [10, 2] } })
+        result3 (mgcol/find-one-as-map coll { :counter { "$mod" [11, 1] } })]
+    (is (= doc1 result1))
+    (is (= doc2 result2))
+    (is (empty? result3))))
+
+
+;; $ne
+
+(deftest query-with-find-one-as-map-using-$ne
+  (let [coll "docs"
+        doc1 { :_id (ObjectId.) :counter 25 }
+        doc2 { :_id (ObjectId.) :counter 32 }
+        _    (mgcol/insert-batch coll [doc1 doc2])
+        result1 (mgcol/find-one-as-map coll { :counter { "$ne" 25 } })
+        result2 (mgcol/find-one-as-map coll { :counter { "$ne" 32 } })]
+    (is (= doc2 result1))
+    (is (= doc1 result2))))