[skoodge]

Since all programs have to be compiled to boolean gates and these gates have to be encrypted, there is a difference of a few orders of magnitude between running programs natively on a CPU (which can of course use highly optimized arithmetical instructions) and running programs over MPC.

In the end, it all depends on the complexity of the program: For simple programs like the Wordle guess/solution comparison (about 40 lines of code, compiled to < 2k gates) the communication overhead is more significant than the computational overhead. The Garbled Circuits protocol used by Tandem needs 7 rounds of communication, so with a round-trip time of 50ms the whole execution takes 350ms.

For more complicated programs, the computational overhead becomes a bit more significant. For programs of > 100k gates, the time to execute a program can range from a few seconds to about a minute. For example, an AES 256 computation requires ~ 9k AND gates and 40k XOR gates.

Right now I would not use it for programs with more than a couple 100k gates, but the engine has not yet been optimized very much, at the moment the focus is on providing a good UX and an easy way for people to experiment with MPC. I'm pretty sure that with a bit of optimization efforts it will be possible to speed it up significantly.