I looked at the public repository at github.com/hypercrux/hypercrux and the project site at hypercrux.com, and examined the published architecture, API, benchmarks, testing methodology and project structure. This is a preliminary engineering assessment based on the repository documentation, not yet an independently executed source-code audit. It covers the released 0.x line; a second engine in development, the Beta, comes up further down. My overall impression is favorable. HyperCrux has a more coherent product proposition than many experimental multimodel databases.