metaborgVersion is now required

content/release/migrate/vnext.md

@@ -1,3 +1,23 @@
 # Spoofax vNext Migration Guide
 
 This is a stub for the migration guide of the upcoming version of Spoofax.
+
+## Metaborg Version in metaborg.yaml
+Before, the value of `metaborgVersion` in `metaborg.yaml` was hardcoded in Spoofax 2 to be `2.6.0-SNAPSHOT`. From now on, it is no longer hardcoded and must be explicitly specified in the `metaborg.yaml` file of a language project. For example:
+
+```yaml
+---
+id: org.metaborg:mylang:1.0.0
+name: mylang
+metaborgVersion: 2.6.0-SNAPSHOT
+# ...
+```
+
+If this is not done, the following error can occur:
+
+```
+MissingDependencyException: Language for dependency org.metaborg:org.metaborg.meta.lang.spt:2.5.20 does not exist
+```
+
+
+

content/release/note/vnext.md

@@ -9,4 +9,4 @@ See the corresponding [migration guide](../migrate/vnext.md) for migrating from
 ## Added
 
 ## Changes
-
+- The value of `metaborgVersion` in `metaborg.yaml` is no longer hardcoded and must be specified explicitly in the `metaborg.yaml` file of a language project. See the migration guide.