1 files changed, 1 insertions, 1 deletions

diff --git a/aoc.cabal b/aoc.cabal
index dda4a43..4b92bb7 100644
--- a/aoc.cabal
+++ b/aoc.cabal
@@ -36,6 +36,6 @@ executable Day03
 
 executable Day04
   main-is:             Day04.hs
-  build-depends:       base, parsec
+  build-depends:       base, parsec, containers
   default-language:    Haskell2010
   hs-source-dirs:      execs