Our function-as-a-service (FaaS) framework transformed end users' questions into automated tests for scientific software. Our case study illustrates the FaaSification of scientific software testing and the importance of value-driven evaluations by focusing on real-world defect detection.MANY SCIENTIFIC RESEARCHERS rely on software to perform their research. In climate research, for instance, scientists and policy makers rely on code simulations to inform their recommendations and decisions. 1 Because scientific software needs to produce trustworthy results, rigorous software engineering practices should be adopted to assure quality.Although testing is a mainstream approach toward software quality, scientific software developers face many challenges, 2 one of which is that only a small group of scientific domain experts (SDEs) who are software developers themselves could write the tests in relation to the scientific theories and models, and yet their primary goal is to further science. 3 Fortunately, science is a community endeavor, and the user community is the cornerstone underlying the sustainable development of any scientific software. However, without the proper tools, serving the user community poses additional burdens on the SDE developers.To alleviate the burdens, we present a function-as-a-service (FaaS) framework aiming to support the SDEs in efficiently processing software users' questions and further transforming the questions into automatic tests. Because users raise their concerns on an asneeded basis, building a monolithic service (for example, via the traditional web clientserver architecture) with availability and capacity would not be cost-effective. FaaS breaks the monolith into functions that can be separately instantiated, executed, and destroyed, and hence, reduces the operational cost. The functions in our work are extracted from the software forum's posts and transformed into system-level test cases. For example, the two functions, increase_bio_retention_cells() and decrease_ runoff(), are generated from the post expressing, "the simulated surface water runoff is expected to decrease when bioretention cells are added to an area of study."