01
Purpose and Domain First, Not Technology
Before writing a single line, I align on what success looks like — business goals, risks, users, metrics — and translate that into domain language: concepts, invariants, processes, exceptions, and rules. For complex domains, I apply DDD so the model becomes a communication and decision tool, not a decorative diagram.
02
UX as a System: Clarity, Consistency, Zero Friction
UX isn't about making things pretty — it's about reducing cognitive load, anticipating errors, guiding decisions, and helping users move forward with confidence. I design flows, states, empty states, permissions, latencies, errors, and happy paths with the same rigor as an API. The experience must be predictable, accessible, and consistent across all screens.
03
UI as a Modular Product: Atomic Design + Design System
The interface is built as a system: reusable components, tokens, variants, states, and hierarchical composition. With Atomic Design I maintain order, scalability, and visual/functional coherence (atoms → molecules → organisms → templates → pages). This reduces the cost of change and avoids spaghetti UI.
04
Layered Architecture with Clear Boundaries
Separating responsibilities isn't dogma — it's sustainable velocity. I define boundaries (domain, application, infrastructure, presentation), stable contracts, and correct dependencies. When appropriate, I apply hexagonal architecture to decouple the core from databases, messaging, external providers, and frameworks, allowing pieces to change without rewriting the system.
05
SOLID and Patterns… with Pragmatic Judgment
I use principles like SOLID and patterns (Repository, Strategy, Factory, Adapter, Facade, CQRS when needed) to manage real complexity: testability, safe extension, coupling reduction, and code comprehension. Patterns are tools; the goal is for the system to be readable, predictable, and easy to evolve.
06
Security by Design: From Model to Deployment
Security isn't added at the end. I make it an architectural requirement: authentication, authorization, isolation, traceability, encryption, secrets management, rate limiting, hardening, and boundary validation. I rely on standards and checklists to leave no gaps — for example, ASVS-style checks and OWASP's Secure-by-Design approach.
07
Performance as a Feature: Measurable Latency, Cost, and Scalability
I don't optimize by intuition — I measure, profile, and measure again. I design with extreme performance in mind when needed: caching, queues and async, real pagination, backpressure, proper index usage, payload minimization, and consistency strategies. The goal: fluid experience, stability, and controlled cost under load.
08
Managed State and Complexity: Operational Simplicity
In frontend and backend, state is modeled explicitly — not hidden in side effects. I differentiate local state vs. application state, define sources of truth, and use Facades to isolate frameworks and prevent the UI from knowing internal details. Result: fewer ghost bugs, more predictability, cheaper refactors.
09
Industrial Quality: Testing, Observability, Living Documentation
Quality isn't negotiated — it's automated. I apply the testing pyramid (unit, integration, e2e when valuable), stable contracts, linters, CI, and a real definition of done. Plus, I include observability: useful logs, metrics, traces, correlation, and alerts. And I document the essential minimum, but always actionable and maintainable: ADRs, diagrams, operational READMEs, deployment guides, and runbooks.
10
Incremental Delivery and Change Management: Continuous Value, Minimal Risk
I build vertically: small complete pieces that reach production with confidence. I work with cadence, feedback, and adaptation, aligned with Scrum principles: iteration, inspection, and adaptation to control risk and maximize value. The architecture accompanies the roadmap and evolves without blocking the team.