The UVM Express is a collection of techniques, coding styles and UVM usages that are designed to increase the productivity of functional verification. The techniques include raising the abstraction level of tests, writing tests using BFM function and task calls, adding functional coverage, and adding constrained-random stimulus generation. If you don’t have a full-time verification expert on staff, or if you are not a full-time verification engineer, UVM Express might be for you. Most verification teams do not have a full-time verification expert on staff, have time and budget restrictions and cannot adopt the UVM in whole or adopt it as quickly as they might like. These teams are usually under-staffed, under-funded and over-worked. They are exactly the kind of people that the UVM is meant to help, but the first step towards adoption is too high.
The UVM Express can be thought of as a series of steps or train stops on a journey that may ultimately lead to Full UVM. At each point in this train journey value is being added to the testbench. Each stop provides value. The choice to move to the next stop is an individualized choice. Some users find getting organized with a BFM is good enough. But usually, they continue and add coverage, only to find that coverage is insufficient. Then they move to improving their stimulus and refining their coverage. It is not a requirement that a testbench move along each stop. Nor is it a requirement that a testbench move to "Full UVM". UVM Express adds value with each stop on the journey.
UVM Express provides a first step toward UVM adoption. UVM Express is a way to build your testbench environment, a way to raise your abstraction level, a way to check the quality of your tests and a way to think about writing your tests. Each of the steps outlined for UVM Express is a reusable piece of verification infrastructure. These UVM Express steps are a way to progressively adopt a UVM methodology, while getting verification productivity and verification results at each step. Using UVM Express is not a replacement for full UVM, but instead enables full UVM migration or co-existence at any time. UVM Express is UVM – just organized in a way that allows progressive adoption and a value proposition with each step.
You are encouraged to first view Evolving Verification Capabilities by Harry Foster that provides the framework for all of the Academy courses.