eXtremeDB/rt is the first and only deterministic embedded database management system for mission- and safety-critical hard real-time applications. Modern avionics and aircraft navigation systems, driver assistance systems, critical medical equipment and similar systems’ data management is complex, often non-interruptible and have strict requirements for timely execution. Those requirements are defined as real-time constraints on the systems’ temporal behavior. The eXtremeDB/rt pioneering design addresses those constraints through preserving the temporal validity of data and enforcing predictable execution of critical data transactions. eXtremeDB/rt offers: Deterministic ACID-compliant transactions eXtremeDB/rt provides transaction semantics for passing the transaction’s deadline and transaction priority to the database scheduler, while the eXtremeDB/rt kernel enforces these deadlines. At the same time, the kernel preserves strong internal database consistency through enforcing the ACID transactions’ properties. Adaptable real-time transaction managers The eXtremeDB/rt transaction manager is based on a preemptive High Priority Earliest Deadline First (EDF) scheduling algorithm. An alternative transaction manager makes use of the priority inheritance protocol (PIP) implemented by most modern real-time operating systems. Regardless of the choice, the real-time transactions deadlines are fully enforced. No restrictions on execution patterns The eXtremeDB/rt transaction managers adapt to the underlying OS schedulers, yet do not make any assumptions about transactions patterns and/or the applications’ data flow. The schedulers can handle periodic and aperiodic transactions and do not require any execution-time estimates to enforce transactions’ deadlines. Highly configurable database kernel While preserving fully deterministic real-time transaction control, the eXtremeDB/rt kernel can be easily tailored for the specific needs of target applications. Source-code level kernel configurations can include only features required by the target applications, excluding unnecessary database management code. Broad RTOS Support In order to satisfy hard real-time requirements, the eXtremeDB/rt target applications must run in the context of a real-time operating system. eXtremeDB/rt is available for all major commercial RTOS including those that are certified to airborne safety (DO-178B/C ) and automotive safety (ISO 26262) specifications on selected hardware.