Add note about using spago alongside spago-legacy

README.md

@@ -179,7 +179,7 @@ This section contains a collection of mini-recipes you might want to follow in o
 
 ### Migrate from `spago.dhall` to `spago.yaml`
 
-You'll need to use [spago-legacy] for this:
+You'll need to use [spago-legacy] for this.
 
 ```bash
 # Install spago-legacy
@@ -191,8 +191,14 @@ spago migrate
 # Ready to remove the dhall files and move to the new spago
 npm install spago@next
 rm spago.dhall packages.dhall
+
+# Replace spago-legacy with this spago
+# since the two use the same NPM package. See next paragraph.
+npm install spago@next
 ```
 
+**Note**: both `spago-legacy` and `spago` use the same NPM package name `spago`. The difference is their version numbers. `spago-legacy` stops at `spago@0.21.0` whereas `spago` is `spago@0.93.X`. If `spago-legacy` is installed globally, `spago` can be installed locally via `npm i spago@next` and then used by prefixing `spago` commands with `npx` (e.g. `npx spago build`).
+
 Some packages might not be found or have the wrong version, in which case
 you'll have to carefully:
 - try to run `spago install some-package` for packages found in the package set (see [how to query the set](#querying-package-sets))