Patch ring-core project.clj to build locally using lein.
Index: ring-clojure/ring-core/project.clj
===================================================================
--- ring-clojure.orig/ring-core/project.clj
+++ ring-clojure/ring-core/project.clj
@@ -4,17 +4,18 @@
   :scm {:dir ".."}
   :license {:name "The MIT License"
             :url "http://opensource.org/licenses/MIT"}
-  :dependencies [[org.clojure/clojure "1.5.1"]
-                 [ring/ring-codec "1.0.1"]
-                 [commons-io "2.5"]
-                 [commons-fileupload "1.3.2"]
-                 [clj-time "0.11.0"]
-                 [crypto-random "1.2.0"]
-                 [crypto-equality "1.0.0"]]
+  :dependencies [[org.clojure/clojure "1.10.x"]
+                 [ring/ring-codec "debian"]
+                 [commons-io "debian"]
+                 [commons-fileupload "debian"]
+                 [clj-time "debian"]
+                 [crypto-random "debian"]
+                 [crypto-equality "debian"]]
   :aliases {"test-all" ["with-profile" "default:+1.6:+1.7:+1.8" "test"]}
   :profiles
-  {:provided {:dependencies [[javax.servlet/servlet-api "2.5"]]}
-   :dev {:dependencies [[javax.servlet/servlet-api "2.5"]]}
+  {:provided {:dependencies [[javax.servlet/servlet-api "debian"]]}
+   :dev {:dependencies [[javax.servlet/servlet-api "debian"]]}
    :1.6 {:dependencies [[org.clojure/clojure "1.6.0"]]}
    :1.7 {:dependencies [[org.clojure/clojure "1.7.0"]]}
-   :1.8 {:dependencies [[org.clojure/clojure "1.8.0"]]}})
+   :1.8 {:dependencies [[org.clojure/clojure "1.8.0"]]}}
+  :local-repo "../debian/maven-repo")