diff --git a/README.md b/README.md
index c70037f..34f9e21 100644
--- a/README.md
+++ b/README.md
@@ -60,8 +60,8 @@ Available Commands:
   version     Print version
 
 Flags:
-  -c, --cache         only scan directories once, at startup
-  -f, --filter        enable filtering via query parameters
+  -c, --cache         only scan directories once, at startup (incompatible with --filter)
+  -f, --filter        enable filtering via query parameters (incompatible with --cache)
   -h, --help          help for roulette
   -p, --port uint16   port to listen on (default 8080)
   -r, --recursive     recurse into subdirectories
diff --git a/cmd/root.go b/cmd/root.go
index ac2bee6..004a215 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -55,8 +55,9 @@ func Execute() {
 }
 
 func init() {
-	rootCmd.Flags().BoolVarP(&Cache, "cache", "c", false, "only scan directories once, at startup")
-	rootCmd.Flags().BoolVarP(&Filter, "filter", "f", false, "enable filtering via query parameters")
+	rootCmd.Flags().BoolVarP(&Cache, "cache", "c", false, "only scan directories once, at startup (incompatible with --filter)")
+	rootCmd.Flags().BoolVarP(&Filter, "filter", "f", false, "enable filtering via query parameters (incompatible with --cache)")
+	rootCmd.MarkFlagsMutuallyExclusive("cache", "filter")
 	rootCmd.Flags().Uint16VarP(&Port, "port", "p", 8080, "port to listen on")
 	rootCmd.Flags().BoolVarP(&Recursive, "recursive", "r", false, "recurse into subdirectories")
 	rootCmd.Flags().BoolVarP(&Sort, "sort", "s", false, "enable sorting via query parameters")
diff --git a/cmd/version.go b/cmd/version.go
index 19bcbf8..6b67020 100644
--- a/cmd/version.go
+++ b/cmd/version.go
@@ -10,7 +10,7 @@ import (
 	"github.com/spf13/cobra"
 )
 
-var Version = "0.20.5"
+var Version = "0.20.6"
 
 func init() {
 	rootCmd.AddCommand(versionCmd)