</>01 / EXPERTISE
Full-stack engineering
Web applications, backend services and API integrations.
- C# & ASP.NET
- TypeScript / JavaScript
- React & Next.js
- Node.js
- Python
SENIOR SOFTWARE ENGINEER · TECHNICAL LEAD
Hi, I'm Mark.
I build reliable systems for complex problems.
I'm Mark Guilster A. Ducao, a software engineer with 15 years of experience delivering enterprise applications, banking platforms and integrations. Today I also build with AI-assisted workflows and modern full-stack technology.
BASED IN DAVAO CITY, PHILIPPINESOPEN TO REMOTE COLLABORATION
SYSTEMS / CLOUD / AI ↗TECHNOLOGIES I WORK WITH
TSTypeScriptRReactNNext.jsC#C# / ASP.NETPyPythonDBPostgreSQLAWSAWSAILLM APIs
ABOUT ME
Complex business processes.
Clear, dependable software.
I've worked across enterprise banking, financial operations and business systems since 2011. My experience spans system architecture, production support, cloud migration, stakeholder collaboration and technical leadership.
More about my experience ↗▣
15 yearsProfessional engineering experience
⌘
2011–presentBanking and enterprise software
◇
Cloud & securityAWS modernization and biometrics
✳
AI-assistedFull-stack engineering and workflows
TECHNICAL EXPERTISE
Technologies I work with
Practical engineering experience across applications, data platforms and enterprise architecture.
◈02 / EXPERTISE
Data & cloud platforms
Relational modeling, query optimization, cloud modernization and delivery.
- PostgreSQL
- SQL Server
- MySQL
- AWS cloud migration
- Docker & CI/CD
✳03 / EXPERTISE
AI & architecture
AI-assisted engineering, enterprise systems and safe workflow automation.
- LLM APIs
- Claude Code
- n8n automation
- REST integrations
- System architecture & RBAC
Skills are listed from my résumé, without invented proficiency percentages or certifications.
SELECTED ENGINEERING EXPERIENCE
Systems I've helped deliver
A selection of real enterprise systems described in my professional experience. No confidential implementation details or client metrics are disclosed.
FINANCIAL SYSTEMS
Merchant settlement & reconciliation
Designed and developed a POS Merchant Settlement & Reconciliation System supporting financial transaction processing and reporting.
C#ASP.NETSQL Server
BANKING INTEGRATIONS
ATM settlement & reconciliation
Engineered ATM settlement and reconciliation for On-Us, Interbranch, and Interbank transactions, with accounting workflows and reporting.
Transaction processingSQLIntegration
ENTERPRISE SECURITY
Biometrics authentication platform
Served as technical lead for an enterprise face and fingerprint biometrics platform for secure authentication and identity verification.
System architectureSecurityTechnical leadership
CURRENT PORTFOLIO / EXPLORATIONS
What I'm exploring next
AI agents, intelligent customer interactions and reconciliation automation. Each published project shows its actual maturity.
LET'S WORK TOGETHER
Have a complex
problem to solve?
From enterprise integrations to AI-assisted applications, I'm interested in work where sound engineering makes a real difference.
Start a conversation ↗