Abstract: Apparatus and method for a scalable pricing engine. A scalable pricing engine is operable in a low-scale mode and a high-scale or scalable mode to process pricing data in response to pricing requests. The pricing engine operates in a first runtime environment in the low-scale mode in which it can service pricing requests up to a threshold number and in which the pricing data can be updated and tested. The pricing engine also operates in a second runtime environment which is a scalable runtime supporting pricing requests above the specified threshold. The scalable runtime and pricing engine rely on a scalable read-only data service which distributes a read-only copy of at least a portion of the pricing data from the primary database, a high-scale cache to reduce access latency, data processing and network resource allocations, and data reduction techniques when processing requests and responses.