C o n s i s t ent * Complete * W e l l D o c u m e n t e d * E a s y t o R e u s e * * E v a l u a t e d * O O P S L A * Artifact * A E C Optimizing Hash-Array Mapped Tries for Fast and Lean Immutable JVM Collections Michael J. Steindorfer Centrum Wiskunde & Informatica, The Netherlands Michael.Steindorfer@cwi.nl Jurgen J. Vinju Centrum Wiskunde & Informatica, The Netherlands TU Eindhoven, The Net