This document discusses building a minimal viable product (MVP) by first creating a minimal testable product (MTP). An MTP has the core functionality of the intended product but is not fully-featured or polished. It is built by a small team using the intended software stack and targets early adopters. The MTP should have the fewest possible features needed to test assumptions about market viability and usability. Features are added incrementally based on testing results to iteratively evolve the MTP into a full MVP. Usability testing is critical and involves crowdsourcing users to provide feedback to inform further development.