Proof01
Complex business systems
Commission, tax, invoicing, payment, document-processing, and role-aware workflows built around explicit business rules.
I build the systems behindcomplex digitalproducts.
SystemDecision engineRules become behavior
- InputsIntent and constraints
- RulesExplicit business logic
- ServicesSystem capabilities
- DataState and history
- InterfacesOperable complexity
- OutputsResults and leverage
Full-Stack Software Engineer Galați, Romania
Full-stack engineering across marketplace infrastructure, financial workflows, automation, analytics, integrations, and product interfaces.
- Identity
- Ionuț-Alexandru Necula
- Current
- Full-Stack Developer at IV Future
01 / Evidence
Complexity becomes visible behavior.
Three recurring forms of proof, expressed as mechanisms rather than claims.
Proof02
Architecture with ownership
Systems carried from data models and service boundaries through product interfaces, delivery, and production behavior.
Proof03
Operational leverage
Translation, release, analytics, import, and content tooling that turns repeated operational work into durable workflows.
02 / Working systems
The work is the evidence.
Each record becomes a technical exhibit: architecture, behavior, and implementation context advance together.
0107 / Featured system
PingLens - AI-Powered Web Analytics Platform
A production-ready, privacy-focused web analytics platform with an integrated AI 'Data Analyst' that uses Text-to-SQL to answer natural language questions about your data. Built with TypeScript, Express.js, React, and PostgreSQL.
Enter case study0207 / Featured system
JurisLogic - Headless Tax & Commission Microservice
An independent personal project exploring multi-jurisdiction tax and commission logic with hexagonal architecture, decimal-safe calculations, and public statutory rates.
Enter case study0307 / Featured system
Rate Limit Project - Algorithm Comparison from Scratch
A production-ready rate limiting solution implementing Fixed Window Counter and Sliding Window Log algorithms from scratch with pluggable storage backends, per-client configuration, and tests that prove exactly where the fixed window fails.
Enter case study0407 / Featured system
TaskFlow - Real-Time Collaborative Task Manager
A collaborative task management application with teams, real-time sync, live notifications, and role-based access - built with Next.js 15 and Convex to explore reactive database subscriptions and event-driven communication patterns.
Enter case study0507 / Featured system
Modular E‑Commerce Platform
A fully modular e-commerce platform built as a Turborepo monorepo with a Fastify backend, Astro storefront (React islands), React + Vite admin panel, and three shared packages - featuring dynamic RBAC, convention-based route auto-registration, and background job processing.
Enter case study0607 / Featured system
Microservices Starter Kit
A production-ready microservices architecture with 5 NestJS services (API Gateway, Auth, Users, Products, Payments) communicating entirely through RabbitMQ events, each with its own PostgreSQL database, deployed on Kubernetes with full CI/CD.
Enter case study0707 / Featured system
Jewelry Store - Full-Stack E-Commerce Platform
A complete production-grade e-commerce platform for jewelry retail - two Next.js frontends (customer storefront with Material-UI + admin dashboard with Tailwind CSS), an Express.js API, Stripe payment processing, transactional emails via Brevo, and automated PDF invoice generation.
Enter case studyNatural-language question
LLM provider
Generated SQL
Validation 01
Validation 02
Validation 03
Validation 04
Validation 05
Read-only database
Analytics response
0107 / Featured system
PingLens - AI-Powered Web Analytics Platform
A production-ready, privacy-focused web analytics platform with an integrated AI 'Data Analyst' that uses Text-to-SQL to answer natural language questions about your data. Built with TypeScript, Express.js, React, and PostgreSQL.
Enter case studyNatural-language question
LLM provider
Generated SQL
Validation 01
Validation 02
Validation 03
Validation 04
Validation 05
Read-only database
Analytics response
0207 / Featured system
JurisLogic - Headless Tax & Commission Microservice
An independent personal project exploring multi-jurisdiction tax and commission logic with hexagonal architecture, decimal-safe calculations, and public statutory rates.
Enter case studyTransaction
Jurisdiction
Tax strategy
Rule pipeline
Decimal-safe result
Audit / cache / queue
0307 / Featured system
Rate Limit Project - Algorithm Comparison from Scratch
A production-ready rate limiting solution implementing Fixed Window Counter and Sliding Window Log algorithms from scratch with pluggable storage backends, per-client configuration, and tests that prove exactly where the fixed window fails.
Enter case studyFixed windowBoundary burst
Sliding windowPrecise limit
0407 / Featured system
TaskFlow - Real-Time Collaborative Task Manager
A collaborative task management application with teams, real-time sync, live notifications, and role-based access - built with Next.js 15 and Convex to explore reactive database subscriptions and event-driven communication patterns.
Enter case studyUser mutation
Convex service
Data update
Reactive query
Client A
Client B
Client C
0507 / Featured system
Modular E‑Commerce Platform
A fully modular e-commerce platform built as a Turborepo monorepo with a Fastify backend, Astro storefront (React islands), React + Vite admin panel, and three shared packages - featuring dynamic RBAC, convention-based route auto-registration, and background job processing.
Enter case studyFastify backend
Astro storefront
React admin
Shared UI
Utilities
Configuration
PostgreSQLRedis / BullMQTurborepo graph
0607 / Featured system
Microservices Starter Kit
A production-ready microservices architecture with 5 NestJS services (API Gateway, Auth, Users, Products, Payments) communicating entirely through RabbitMQ events, each with its own PostgreSQL database, deployed on Kubernetes with full CI/CD.
Enter case studyRabbitMQ topic exchange
Gateway
Isolated dataAuth
Isolated dataUsers
Isolated dataProducts
Isolated dataPayments
Isolated data0707 / Featured system
Jewelry Store - Full-Stack E-Commerce Platform
A complete production-grade e-commerce platform for jewelry retail - two Next.js frontends (customer storefront with Material-UI + admin dashboard with Tailwind CSS), an Express.js API, Stripe payment processing, transactional emails via Brevo, and automated PDF invoice generation.
Enter case studyCheckout session
Hosted payment
Verified webhook
Idempotent order update
Email / invoice
03 / Capability map
Systems shipped.
Select a domain to trace the responsibility from business behavior to operational outcome.
Selected domain
Financial logic
Commission calculation, tax strategies, invoicing, payments
04 / Written reasoning
The decisions behind the diagrams.
Technical notes on architecture, business rules, failure modes, and production behavior extend the evidence beyond each system map.
05 / Production history
Ownership, under real constraints.
Four years of full-stack ownership across multi-tenant product architecture, financial business logic, automation, integrations, and production operations.
01Oct 2022 / Present
Full-Stack Developer
IV FutureFull-stack ownership across multi-tenant product architecture, financial business logic, automation, integrations, and production operations.
System responsibilityDesign plugin-based, service-oriented modules with dependency injection across multiple product lines, cutting feature development time and isolating change.
06 / Closing loop
The output is a conversation.
If this work overlaps a problem you own, or you have a question about a record, email is the most direct route.