Model transformations play a key role in model driven software engineering approaches. Validation of model transformations is crucial for the quality assurance of software systems to be constructed. The relational logic based specification language Alloy and its accompanying tool the Alloy Analyzer have been used in the past to validate properties of model transformations. However Alloy based analysis of transformations suffers from time complexity and scalability issues. The problem becomes

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... n more severe when it comes to higher order transformations that are inherently more complex. In previous work, we proposed a sub-language of Alloy, called F-Alloy, that is tailored for model transformation specifications. Instead of pure analysis based validation, F-Alloy speeds up the validation of model transformations by applying a hybrid strategy that combines analysis with interpretation. In this paper, we show how the F-Alloy approach can be extended to also support efficient validation of higher order transformations.