diff --git a/flake.nix b/flake.nix
index 7860a10..9e55396 100644
--- a/flake.nix
+++ b/flake.nix
@@ -45,6 +45,10 @@
             aeson
             random
             neat-interpolation
+
+            # graphing libraries!
+            Chart
+            Chart-cairo
           ]
         );
       in
diff --git a/src/projectEuler/question9.hs b/src/projectEuler/question9.hs
index 9958920..1b0f549 100644
--- a/src/projectEuler/question9.hs
+++ b/src/projectEuler/question9.hs
@@ -1,3 +1,5 @@
+import           Graphics.Rendering.Chart.Backend.Cairo
+import           Graphics.Rendering.Chart.Easy
 {-
 Special Pythagorean Triplet
 Problem 9