New 5.0 release generates specifications and integration tests from the running application and modernizes databases to PostgreSQL
vFunction announced vFunction 5.0, a release that brings large existing Java and .NET applications into AI-driven development.
vFunction 5.0 adds specifications and integration tests generated from the running application, modernizes SQL Server, Oracle, and DB2 databases to PostgreSQL in the same workflow. It delivers these results to Kiro, Claude Code, AWS Transform, and other AI coding tools through vFunction’s MCP server and downloadable skills.
The cost of waiting to modernize these applications is going up fast, and the cost of modernizing has never been lower.”
— Moti Rafalin, vFunction CEO & Co-Founder
AI coding tools excel at writing code, but on a large existing application, they still lack a model of what the system does, an agreed target for what it should become, and a way to prove a change didn’t break anything. vFunction 5.0 supplies all three from the running application: it observes production behavior, gives the customer’s architects the evidence to define the target architecture, and generates the specifications and tests from that same behavior. vFunction is built for applications past roughly 500,000 lines of code or 1,000 classes.
Marketing Technology News: MarTech Interview with Jema Birkmeyer, VP @ Attentive
“The cost of waiting to modernize these applications is going up fast, and the cost of modernizing has never been lower. With 5.0, a team can modernize its largest application domain by domain and verify each change before the next one begins,” said Moti Rafalin, CEO and co-founder of vFunction.
What’s new in vFunction 5.0
– Specifications from production behavior. Each domain of an application gets a specification generated from analysis of the running system. Every element is backed by evidence observed at runtime or derived from the code, and the architectural issues flagged for that domain are factored in, so generated code does not reintroduce them.
– Generate integration tests. Tests derived from real observed production traffic give an application substantial integration coverage before the first change, including applications never covered by tests, and prove the new code behaves like the old.
– Database migration to PostgreSQL. SQL Server, Oracle, and DB2 databases migrate as a step in the same workflow: schema and SQL dialect conversion, driver and connection pool updates, the ORM switched to Hibernate for Java or EF Core for .NET, and AI-powered conversion of stored procedures to application code. Moving the data itself is done with the customer’s database tooling.
Marketing Technology News: How MarTech Is Enabling Autonomous Brand Engagement Across Channels?
The release adds a downloadable skill that generates code from a specification one domain at a time, plus direct installation and authentication for the Claude Code and Kiro command-line tools. It also includes AWS Transform for Java workflows alongside .NET, and a new Modernization tab that runs the end-to-end workflow for an application in one place. Full details are on the vFunction website.
“A specification inferred from code repeats the code’s problems. In 5.0 the specification and the tests come from the runtime behavior, and take into account observed architecture issues, which lets a coding tool modernize a domain of a half-million-line application while reducing its dependencies on other modules,” said Amir Rapson, CTO and co-founder of vFunction.
vFunction 5.0 is delivered the way every vFunction engagement runs: vFunction’s forward-deployed engineers run the process with the customer’s team, inside the customer’s environment, until the team can run it alone. The combination of vFunction’s unique modernization harness, the leading AI coding tools, and vFunction’s FDEs allows rapid, low risk and fixed cost modernization engagements.
