Maintainable Freedom Dumlao: What 70 Java Services Taught Me About Focus
Freedom Dumlao (CTO at Vestmark) joins Robby to explore what it means to maintain software at scale—and why teams sometimes need to unlearn the hype.
With two decades of experience supporting financial systems, Freedom shares how his team manages a Java monolith that oversees $1.6 trillion in assets. But what’s most surprising? His story of how a team working on 70+ microservices rebuilt their platform as a single Ruby on Rails monolith—and started shipping faster than ever before.
Episode Highlights
[00:02:00] Why Respecting Legacy Code Matters
Freedom reflects on a lesson he learned at Amazon: "Respect what came before." He discusses the value of honoring the decisions of past developers—especially when their context is unknown.
[00:05:00] How Tests Help (and Where They Don’t)
Freedom discusses how tests can clarify system behavior but not always intent—especially when market logic or business-specific rules come into play.
[00:07:00] The Value of Understudies in Engineering
Freedom shares how his team intentionally pairs subject matter experts with understudies to reduce risk and transfer knowledge.
[00:09:30] Rethinking Technical Debt
He challenges the fear-based framing of technical debt, comparing it instead to a strategic mortgage.
[00:17:00] From 70 Services to 1 Monolith
At FlexCar, Freedom led an unconventional rewrite—consolidating 70 Java microservices into a single Rails app. The result? A dramatic increase in velocity and ownership.
[00:25:00] Choosing Rails Over Phoenix, Laravel, and Django
After evaluating multiple frameworks, Rails' cohesiveness, Hotwire, and quick developer ramp-up made it the clear winner—even converting skeptical team members.
[00:31:00] How Rails Changed Team Dynamics
By reducing dependency handoffs, the new Rails app enabled solo engineers to own complete features. The impact? Faster delivery and more engaged developers.
[00:36:30] Why Rails Still Makes Sense at a 20-Year-Old Company
Even with a large Java codebase, Vestmark uses Rails for rapid prototyping and new product development.
[00:41:00] Using AI to Navigate Legacy Systems
Freedom explains how his team uses retrieval-augmented generation (RAG) to surface relevant code—but also the limitations of AI on older or less common codebases.
[00:51:00] Seek Feedback, Not Consensus
Freedom explains why aiming for alignment slows teams down—and how decision-makers can be inclusive without waiting for full agreement.
Links and Resources
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