diff --git a/aoc.asd b/aoc.asd
index 28db69e..7ae8af8 100644
--- a/aoc.asd
+++ b/aoc.asd
@@ -31,4 +31,4 @@
                 :components
                 ((:file "main"))))
   :description "Test system for aoc"
-  :perform (test-op (op c) (symbol-call :rove :run c)))
+  :perform (test-op (op c) (symbol-call :parachute :test :aoc/tests)))
diff --git a/src/2018/day06.lisp b/src/2018/day06.lisp
index 005d118..5ea9bf3 100644
--- a/src/2018/day06.lisp
+++ b/src/2018/day06.lisp
@@ -1,14 +1,39 @@
 (defpackage :aoc/2018/06
-  (:use :cl :aoc))
+  (:use :cl :aoc)
+  (:export
+   #:vector-2d
+   #:make-vector-2d
+   #:vector-2d-x
+   #:vector-2d-y
+   #:vector-2d-sub
+   #:manhattan-distance
+   #:sample-points
+   #:top-left
+   #:bottom-right))
 
 (in-package :aoc/2018/06)
 
-(defvar input-data (test-input 2018 6))
+(defun parse-line (s)
+  (map 'list #'parse-integer (cl-ppcre:split ", " s)))
 
-(defstruct point-2d
+(defvar input-data '())
+(setf input-data (map 'list #'parse-line (test-input 2018 6)))
+
+(defstruct vector-2d
   (x 0 :type fixnum)
   (y 0 :type fixnum))
 
+(defun vector-2d-sub (p1 p2)
+  (make-vector-2d
+   :x (- (vector-2d-x p1) (vector-2d-x p2))
+   :y (- (vector-2d-y p1) (vector-2d-y p2))))
+
+(defun manhattan-distance (p1 p2)
+  (let ((diff (vector-2d-sub p1 p2)))
+    (+
+     (abs (vector-2d-x diff))
+     (abs (vector-2d-y diff)))))
+
 (defvar sample-data '((1 1)
                       (1 6)
                       (8 3)
@@ -16,18 +41,21 @@
                       (5 5)
                       (8 9)))
 
-(defun make-points (data)
-  (map 'list (lambda (p) (make-point-2d :x (first p) :y (second p))) data))
 
-(defvar sample-points (make-points sample-data))
 
-(defun top-left (points)
-  (let ((x-min (apply #'min (map 'list #'point-2d-x points) ))
-        (y-min  (apply #'min (map 'list #'point-2d-y points) )))
-    (make-point-2d :x x-min :y y-min)))
+(defun make-vectors (data)
+  (map 'list (lambda (p) (make-vector-2d :x (first p) :y (second p))) data))
 
-(defun bottom-right (points)
-  (let ((x-max (apply #'max (map 'list #'point-2d-x points) ))
-        (y-max  (apply #'max (map 'list #'point-2d-y points) )))
-    (make-point-2d :x x-max :y y-max)))
+(defvar sample-points (make-vectors sample-data))
+(setf sample-points (make-vectors sample-data))
+
+(defun top-left (vectors)
+  (let ((x-min (apply #'min (map 'list #'vector-2d-x vectors) ))
+        (y-min  (apply #'min (map 'list #'vector-2d-y vectors) )))
+    (make-vector-2d :x x-min :y y-min)))
+
+(defun bottom-right (vectors)
+  (let ((x-max (apply #'max (map 'list #'vector-2d-x vectors) ))
+        (y-max  (apply #'max (map 'list #'vector-2d-y vectors) )))
+    (make-vector-2d :x x-max :y y-max)))
 
diff --git a/src/main.lisp b/src/main.lisp
index 604e6d7..19a0033 100644
--- a/src/main.lisp
+++ b/src/main.lisp
@@ -1,7 +1,8 @@
 (defpackage aoc
   (:use :cl)
   (:export
-   #:test-input))
+   #:test-input
+   #:clear-data-cache))
 
 (in-package :aoc)
 
@@ -35,6 +36,8 @@
                   :secure-p t))))
 
 
+(defun split-lines (s)
+  (cl-ppcre:split "\\n" s))
 
 
 (defun fetch-input-data (year day)
@@ -42,11 +45,14 @@
     (multiple-value-bind
 	  (body)
 	(dex:get url :cookie-jar *cookie-jar* :verbose t)
-      body)))
+      (split-lines body))))
 
 
 (defvar *input-data-cache* (make-hash-table))
 
+(defun clear-data-cache ()
+  (setf *input-data-cache* (make-hash-table)))
+
 (defun test-input (year day)
   "Return input data for the given challenge. Use a cached value if already fetched"
   (let* ((key (+  (* year 100) day))
diff --git a/test/2018/day06-test.lisp b/test/2018/day06-test.lisp
index 1d21af8..f43b145 100644
--- a/test/2018/day06-test.lisp
+++ b/test/2018/day06-test.lisp
@@ -1,16 +1,26 @@
-(defpackage :aoc/2018/06
-  (:use :cl :aoc :parachute))
+(defpackage :aoc/2018/06/tests
+  (:use :cl :aoc :aoc/2018/06 :parachute))
 
-(in-package :aoc/2018/06)
+(in-package :aoc/2018/06/tests)
 
 (define-test suite-2018-06)
 
 (define-test+run find-top-left
   :parent suite-2018-06
   (let ((result (top-left sample-points)))
-    (true (equalp (make-point-2d :x 1  :y 1) result))))
+    (true (equalp (make-vector-2d :x 1  :y 1) result))))
 
 (define-test+run find-bottom-right
   :parent suite-2018-06
   (let ((result (bottom-right sample-points)))
-    (true (equalp (make-point-2d :x 8 :y 9) result))))
+    (true (equalp (make-vector-2d :x 8 :y 9) result))))
+
+(define-test test-manhattan-distance
+  :parent suite-2018-06
+  (let ((p0 (make-vector-2d :x 0 :y 0))
+	(p1 (make-vector-2d :x 1 :y 1))
+	(p2 (make-vector-2d :x 3 :y 2)))
+    (true (eq 0 (manhattan-distance p0 p0)))
+    (true (eq 2 (manhattan-distance p0 p1)))
+    (true (eq 5 (manhattan-distance p0 p2)))
+    ))
diff --git a/tests/main.lisp b/tests/main.lisp
index 43d9d34..c4b3a60 100644
--- a/tests/main.lisp
+++ b/tests/main.lisp
@@ -1,11 +1,20 @@
-(defpackage aoc/tests/main
-  (:use :cl
-        :aoc
-        :rove))
-(in-package :aoc/tests/main)
+(defpackage aoc/tests
+  (:use :cl :aoc :parachute
+   :aoc/2018/06 ))
+
+(in-package :aoc/tests)
 
 ;; NOTE: To run this test file, execute `(asdf:test-system :aoc)' in your Lisp.
 
-(deftest test-target-1
-  (testing "should (= 1 1) to be true"
-    (ok (= 1 1))))
+;; top of test suite tree
+(define-test aoc-suite)
+
+
+;; suite for every year
+(define-test suite-2018
+  :parent aoc-suite)
+
+
+(define-test  "should (= 1 1) to be true"
+  :parent aoc-suite
+  (true (= 1 1)))