When fluently building a projection, each call to Include or Exclude creates a new CombinedProjectionDefinition<T> with the projection to that point and the new include/exclude projection. This results in a chain of nested projections. When this chain is rendered, CombinedProjectionDefinition<T>.Render is called recursively. With a large number of included/excluded fields, this can result in significant callstack depth. Although it is unlikely in common cases to overflow the stack, it is possible as demonstrated by the test case. This issue was resolved by flattening nested CombinedProjectionDefinition<T> instances.