FEniCS is an automated finite element library used to solve equations used in modeling, featuring a domain-specific language and automated code generation. Users input a problem that looks very much like mathematical notation; FEniCS then translates that into computer code.
Julia is a fast and user-friendly programming language for high-performance scientific computing.
Stan is a platform for Bayesian modeling, inference, and visualization on the frontiers of applied statistics.
pandas is a data wrangling platform for Python widely adopted in the scientific computing community. pandas provides easy-to-use data ingestion, transformation, and export functions.