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@@ -2,3 +2,6 @@
 Run `sportdb build` in the directory that has `Datafile`.
 
 Correspondence on the topic can be found at [this google groups topic](https://groups.google.com/forum/#!msg/opensport/jYNVDF_QSJA/pyHWWtRqAgAJ).
+
+#### Using the Gemfile
+Sportdb only builds with older versions of ActiveRecord. Use a Gemfile as outlined [here](https://groups.google.com/forum/#!topic/opensport/593H1O7yIdE) to lock the correct version.