The world’s most expensive weapons program is riddled with software bugs. And a previously unreleased December memo from Michael Gilmore, the Department of Defense’s director for Operational Test and Evaluation, states that the F-35’s software will be buggy for years.

Gilmore’s issues center around testing software components. The F-35 is now fixed with a set of interim software components, but will have an entirely different set when the final version is delivered to the Marine Corps and Air Force this summer.

Gilmore specifically called out the craft’s “Autonomic Logistics Information System” as continuing to “struggle in development with deferred requirements, late and incomplete deliveries, high manpower requirements, multiple deficiencies requiring workarounds, and a complex architecture with likely (but largely untested) cyber deficiencies.” Lockheed Martin and the JPO are still trying to get the ALIS software operational — a not insignificant task for software designed for both the aircraft itself as well as its supply chain — and have deferred testing it for weaknesses and bugs.

Having an untested, twitchy software base is especially problematic since new weapons system will be added to the aircraft and it’s uncertain how they’ll interact.

Ars Technica notes that at least one military member of the F-35’s Joint Program Office went to the Facebook page of a defense publication to call Gilmore’s memo “whining.”