Document speedscope global installation

jean-francois-labbe · web-flow · commit bbad9529bd7f · 2023-03-24T14:32:27.000+01:00
Speedscope must be installed globally for the graph to be displayed.
diff --git a/README.md b/README.md
@@ -12,6 +12,8 @@ gem "singed"
 
 Then run `bundle install`
 
+Then run `npm install -g speedscope`
+
 ## Usage
 
 Simplest is calling with a block:
