diff --git a/go.mod b/go.mod
index 847d175..e3924b3 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,7 @@ module github.com/dds/aoc2020
 go 1.15
 
 require (
-	github.com/alecthomas/kong v0.6.1
+	github.com/alecthomas/kong v0.7.1
 	github.com/atotto/clipboard v0.1.4
 	github.com/gdamore/tcell/v2 v2.5.3
 	github.com/stretchr/testify v1.8.0
diff --git a/go.sum b/go.sum
index d878e4c..388aaf1 100644
--- a/go.sum
+++ b/go.sum
@@ -1,7 +1,9 @@
-github.com/alecthomas/kong v0.6.1 h1:1kNhcFepkR+HmasQpbiKDLylIL8yh5B5y1zPp5bJimA=
-github.com/alecthomas/kong v0.6.1/go.mod h1:JfHWDzLmbh/puW6I3V7uWenoh56YNVONW+w8eKeUr9I=
-github.com/alecthomas/repr v0.0.0-20210801044451-80ca428c5142 h1:8Uy0oSf5co/NZXje7U1z8Mpep++QJOldL2hs/sBQf48=
-github.com/alecthomas/repr v0.0.0-20210801044451-80ca428c5142/go.mod h1:2kn6fqh/zIyPLmm3ugklbEi5hg5wS435eygvNfaDQL8=
+github.com/alecthomas/assert/v2 v2.1.0 h1:tbredtNcQnoSd3QBhQWI7QZ3XHOVkw1Moklp2ojoH/0=
+github.com/alecthomas/assert/v2 v2.1.0/go.mod h1:b/+1DI2Q6NckYi+3mXyH3wFb8qG37K/DuK80n7WefXA=
+github.com/alecthomas/kong v0.7.1 h1:azoTh0IOfwlAX3qN9sHWTxACE2oV8Bg2gAwBsMwDQY4=
+github.com/alecthomas/kong v0.7.1/go.mod h1:n1iCIO2xS46oE8ZfYCNDqdR0b0wZNrXAIAqro/2132U=
+github.com/alecthomas/repr v0.1.0 h1:ENn2e1+J3k09gyj2shc0dHr/yjaWSHRlrJ4DPMevDqE=
+github.com/alecthomas/repr v0.1.0/go.mod h1:2kn6fqh/zIyPLmm3ugklbEi5hg5wS435eygvNfaDQL8=
 github.com/atotto/clipboard v0.1.4 h1:EH0zSVneZPSuFR11BlR9YppQTVDbh5+16AmcJi4g1z4=
 github.com/atotto/clipboard v0.1.4/go.mod h1:ZY9tmq7sm5xIbd9bOK4onWV4S6X0u6GY7Vn0Yu86PYI=
 github.com/bobesa/go-domain-util v0.0.0-20190911083921-4033b5f7dd89 h1:2pkAuIM8OF1fy4ToFpMnI4oE+VeUNRbGrpSLKshK0oQ=
@@ -25,6 +27,8 @@ github.com/gonuts/binary v0.2.0 h1:caITwMWAoQWlL0RNvv2lTU/AHqAJlVuu6nZmNgfbKW4=
 github.com/gonuts/binary v0.2.0/go.mod h1:kM+CtBrCGDSKdv8WXTuCUsw+loiy8f/QEI8YCCC0M/E=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1 h1:EGx4pi6eqNxGaHF6qqu48+N2wcFQ5qg5FXgOdqsJ5d8=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
+github.com/hexops/gotextdiff v1.0.3 h1:gitA9+qJrrTCsiCl7+kh75nPqQt1cx4ZkudSTLoUqJM=
+github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg=
 github.com/jtolds/gls v4.20.0+incompatible h1:xdiiI2gbIgH/gLH7ADydsJ1uDOEzR8yvV7C0MuV77Wo=
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
 github.com/keybase/go-keychain v0.0.0-20200502122510-cda31fe0c86d h1:gVjhBCfVGl32RIBooOANzfw+0UqX8HU+yPlMv8vypcg=
@@ -55,7 +59,6 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.7.2/go.mod h1:R6va5+xMeoiuVRoj+gSkQ7d3FALtqAAGI1FQKckRals=
 github.com/stretchr/testify v1.8.0 h1:pSgiaMZlXftHpm5L7V1+rVB+AZJydKsMxsQBIJw4PKk=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/yourbasic/graph v0.0.0-20210606180040-8ecfec1c2869 h1:7v7L5lsfw4w8iqBBXETukHo4IPltmD+mWoLRYUmeGN8=