Systems companies struggle to integrate into complex designs components coming from various providers. The news of recalls and re-certifications in the automotive and aerospace industries is an eloquent testimony to the difficulty of system design. Many voices from government agencies, industry, and academia have thus called for the development of theoretical and practical tools to provide assurance of the correctness of our complex systems.

Assume-guarantee contracts provide a theoretical and methodological framework to compositionally design systems with rigorous guarantees. In this talk, we will introduce contracts and their algebraic operations through case studies in space mission design and autonomous driving that show where current system design methodologies struggle. We will also introduce Pacti, a software package that enables engineers to carry out system-level design using contracts.