Spector felt that the best aspects of Deus Ex's development were the "high-level vision" and length of preproduction, flexibility within the project, testable "proto-missions", and the Unreal Engine license.[44] The team's pitfalls included the management structure, unrealistic goals, underestimating risks with artificial intelligence, their handling of proto-missions, and weakened morale from bad press.[45] Deus Ex was released on June 23, 2000, and published by Eidos Interactive for Microsoft Windows. The team planned third-party ports for Mac OS 9 and Linux.[36]