Hashimoto previously worked for the toy company Bandai. He currently works for Square Enix, which he joined in 1995.
He was the promotions producer for Final Fantasy VII.
When asked at E3 2008 about the possibility of a remake of Final Fantasy VII, he said that Square Enix is aware fans would like that, and that they are very busy making other titles first. As Final Fantasy X-2 and Kingdom Hearts were being completed, the learning experience the team had during the Compilation of Final Fantasy VII project spawned the Fabula Nova Crystallis series which was supposed to build on it.
When Square was sharing a building in Tokyo with the Disney corporation, Hashimoto found himself conversing in an elevator with a Disney executive, and there they conceived of a Disney/Square Enix video game eventually called Kingdom Hearts. Hashimoto has stated that the new features in Kingdom Hearts II were the result of the success of the first game and Disney's increased trust in Square Enix to pull off an excellent product.
While working on Front Mission Evolved, one of the challenges was balancing the speed of the real time battles the wanzers, or mechs, were having so that the game was realistic to the mechs size, but also still fast enough to be engaging.
While discussing Final Fantasy XIII, Hashimoto mentioned that Square Enix has been attempting to make localization of their game releases close the release gap between Japan and the rest of the world.