Reltroner

For Recruiters & Collaborators

  • 2026-04-11 - Published
For Recruiters & Collaborators

Professional overview for recruiters and collaborators seeking a deterministic backend/system engineer

For Recruiters & Collaborators

Hello —
I'm Rei Reltroner (Raidan Sandra), a backend/system engineer specializing in deterministic systems, modular architecture, and secure authentication flows.

I focus on building systems that are not just functional — but auditable, predictable, and production-resilient.

Fast Professional Overview

Role Positioning
Backend / System Engineer (Early Mid-Level)

Primary Focus

  • Backend engineering (Laravel, PHP ecosystem)
  • Modular system architecture (ERP, platform systems)
  • Deterministic data flow & system behavior
  • Authentication systems (OIDC / SSO / JWT)
  • System integrity, auditability, and reliability

Core Strengths

  • Turning ambiguous requirements into structured, production-ready systems
  • Designing modular, scalable architectures (service isolation, layered design)
  • Building deterministic systems (single source of truth, predictable outputs)
  • Implementing secure authentication (Keycloak OIDC, JWT RS256, OAuth2)
  • Handling financial-grade data integrity (immutability, audit logging, snapshot validation)
  • Debugging complex multi-layer issues (UI, SSR, state, API, infra)
  • Writing structured documentation (incident reports, failure analysis, ADRs)

Professional Approach

I build systems with principles:

  • Deterministic over implicit behavior
  • Immutability over mutation risk
  • Clarity over cleverness
  • System boundaries over tight coupling
  • Auditability over hidden state

My goal is to ensure that systems:

  • Behave predictably under load and edge cases
  • Can be debugged without guesswork
  • Are safe to evolve without breaking core integrity

Work Experience

Full-Cycle Solutions Associate — Skill-Wanderer (Remote)

March 2026 – Present

Working in a distributed engineering team (Vietnam / EU) delivering full-cycle product systems.

Key Contributions:

  • Re-architected monolithic course system into modular, factory-driven architecture
  • Eliminated dual source-of-truth issues, ensuring deterministic UI-state synchronization
  • Debugged complex issues across layers (SSR mismatch, reactive bugs, UI blocking)
  • Applied structured Git workflows (clean rebuild, selective restore) for production-grade PRs
  • Owned full lifecycle: architecture → implementation → debugging → delivery

Impact:

  • Reduced bug risk by ~25% via deterministic lifecycle handling
  • Enabled scalable reuse across platform ecosystem
  • Improved system reliability and production readiness

Project Highlight — Reltroner ERP Ecosystem

Role: Backend Engineer (Independent Project)
Stack: Laravel 12, PHP 8.2+, MySQL, Keycloak (OIDC), GitHub Actions
Period: March 2025 – Present

A modular ERP platform with centralized authentication and audit-grade financial systems.

Architecture Highlights:

  • Multi-service system (Gateway, HRM, Finance)
  • Centralized SSO using Keycloak (OIDC)
  • Immutable transaction system (append-only + reversal model)
  • Audit logging + fiscal locking system
  • Snapshot-based financial reporting (deterministic outputs)

System Scale:

  • 3 independent repositories
  • 150+ automated tests (unit, feature, regression)
  • 100+ database migrations

Impact:

  • Delivered HRM & Finance modules end-to-end in ~6 months
  • Reduced onboarding time by ~20% via structured documentation
  • Ensured audit-safe financial reporting with deterministic guarantees

Live HRM Demo:
hrm.reltroner.com

Repositories:

Documentation:

System Engineering Capabilities

Backend & API

  • Laravel 12, PHP 8.2+, Node.js
  • RESTful APIs, service isolation

Architecture

  • Modular systems
  • Dependency Inversion
  • Layered architecture
  • Deterministic system design

Authentication & Security

  • Keycloak (OIDC / SSO)
  • JWT (RS256), OAuth2
  • Trust boundary enforcement
  • Secret remediation & Git history rewriting

Database

  • MySQL, PostgreSQL, SQLite
  • Schema design & migrations
  • Transaction integrity & audit logging

DevOps

  • GitHub Actions (CI/CD)
  • Docker, SSH, DNS/SSL
  • Environment hardening

Testing

  • PHPUnit (unit, feature, regression)
  • Failure-mode analysis
  • Deterministic validation

Documentation

  • Incident reports
  • Architectural Decision Records (ADR)
  • Failure analysis & audit documentation

Notable Engineering Incident

Security Incident — RSA Key Exposure

Handled a real-world security incident involving exposed RSA key.

Actions:

  • Rewrote Git history using git filter-repo
  • Removed all secret traces and sanitized repository
  • Implemented preventive controls (pre-commit hooks, .gitignore)

Result:

  • No production impact
  • No key compromise
  • Improved overall security posture

This reflects my ability to handle high-risk engineering situations with control and precision.

Education

Universitas Andalas — Information Systems (Coursework)

Certifications

Availability

I’m currently open to:

  • Backend Engineer roles (Laravel / PHP)
  • System / Platform Engineering roles
  • SaaS or product-focused teams
  • Remote-first or distributed environments

Contact

📧 studio@reltroner.com
🌐 reltroner.com
💻 github.com/Reltroner
🔗 linkedin.com/in/rei-reltroner

Full CV

You can view my full CV here:

📄 Rei's CV