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docs/how-to/how-to-support-gs64-options.md

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+# How to support GS64 class options
+
+GemStone/S 64 includes some options during class creation that change the
+behavior of the instances.
+
+There's support in Rowan to specify these options using the Tonel format
+by filling the `gs_options` metadata in the class creation section. However,
+by default Pharo will remove this metadata when committing code losing the
+options. To avoid this behavior and retain the options, load the `Tool` group
+and send in the class `initialize` message one of the following messages:
+
+- `makeInstancesDbTransient`
+- `makeInstancesInvariant`
+- `makeInstancesNonPersistent`
+
+This will configure the options as class properties in Pharo, and later the
+Tonel Writer will use these options for the metadata.