Johnathan Blow, developer of the indie cult hit Braid, says he is going into debt to finance the development of his next game, The Witness.

Blow said Braid has earned millions, but it hasn't been enough to fund the full development of The Witness.

Speaking with engadget, Blow said sales of Braid had slowed.

"Braid still sells well on platforms that are thriving, but two of Braid’s big platforms were the Xbox 360 and the PlayStation 3, both of which are sunsetting at this point," Blow said.

"Not so many people are buying digital games there, so the Braid income is not nearly enough any more to fund the team. I have borrowed a bunch of money to finish The Witness. So I hope when it’s done, some people buy the game."

The Witness has been in development since 2009. It was first publicly showcased at the reveal of the PlayStation 4, in February 2013. It is also coming to PC and iOS.

"If there is such a thing as taking ‘too long,’ we have probably already done that," Blow said.

"20 years from now, I am not going to care about whether we took an extra six months or a year in development; I am going to care about the quality of the game people got to play."