John Bryan Logdonio

Full-Stack Software Engineer — ERP & Accounting Systems
Cebu, Philippines·act.jlogdonio@gmail.com·0920 671 0992·jblogdonio.digital
Open to remote work (Philippines / international)

Full-stack software engineer with 4+ years building and maintaining ERP and accounting systems for the Philippine market. I ship across the whole stack — Angular 19 on the frontend, C# Web API and Postgres/Supabase or SQL Server on the backend — and I write the money-path logic myself: GL posting, AR/AP, inventory costing, and BIR-compliant tax handling.

My edge is domain depth. I understand double-entry accounting and Philippine BIR compliance well enough to design the data model and the reports, not just the UI — so the financial software I build is correct, auditable, and ready for inspection.

Read my blog

John Bryan Logdonio seated at a desk in a dark suit, typing on a laptop, with a notebook and pen beside him.
John Bryan Logdonio in a meeting room presenting to two colleagues, a laptop and printed charts on the table and a project dashboard on the wall screen.

Experience

Full-Stack Developer

Myvan Properties and Development Inc. · A Myvan Holdings Inc. company · Cebu / Mandaue City (remote)

Sole/lead developer for the Myvan group's internal business systems, delivering ERP and web work across two stacks — a legacy C# Web API + SQL Server platform and a modern Angular + Supabase platform — plus the group's marketing web presence.

Modern ERP — Angular 19 + Supabase (Postgres)

  • Built a multi-tenant accounting/ERP platform on Supabase (Postgres) with row-level security and custom JWT auth supporting company/branch context switching, isolating each tenant's data on shared infrastructure.
  • Implemented the money path — GL posting, AR/AP, and tax logic — as Postgres RPCs so financial calculations stay correct and consistent across every client that calls them.
  • Developed an Angular 19 frontend using standalone components, signals and signal-based services with PrimeNG 19, delivering data-dense dashboards and printable BIR/accounting reports.
  • Designed BIR-compliant outputs (VAT, EWT, OR vs SI distinctions, books of accounts) so records pass audit and inspection without rework.

Legacy ERP (Pilipinas Steel) — C# Web API + SQL Server 2008

  • Maintained and extended a C# Web API (.NET) + SQL Server 2008 ERP spanning Sales, Inventory, Procurement and Construction modules.
  • Authored T-SQL stored procedures for GL posting, reconciliations and reporting on a legacy SQL 2008 engine, engineering around the absence of OFFSET/FETCH, STRING_SPLIT and JSON support.
  • Tuned slow queries and stored procedures on the tables driving the SO→DR→SI sales flow and inventory costing, improving report and lookup responsiveness.
  • Reconciled subsidiary ledgers against control accounts to keep AR/AP and inventory balances accurate at period close.

Other delivered work for the group

  • Designed and built a new ERP with modular architecture (C# Web API backend, Angular frontend), creating and integrating modules for Procurement, Inventory, Sales, Accounting and Treasury.
  • Built Bill of Materials (BOM) functionality for construction project costing.
  • Maintained and enhanced the company's Enterprise Risk Management (ERM) system, and managed and optimised internal databases for performance and security.
  • Built the Paylalo marketing website in WordPress, delivering the group's public-facing brand site.
June 2022 – Present

IT Help Desk Support

Taskseveryday · Cebu, Philippines
  • Provided software and hardware troubleshooting and network support for employees and agents.
  • Maintained physical network equipment.
June 2019 – June 2022

IT Help Desk Support

Asian College of Technology · Cebu, Philippines

Held concurrently with full-time studies as a working student.

  • Resolved hardware, software and network issues across campus.
  • Maintained firewall and network equipment.
  • Ran basic troubleshooting seminars.
May 2017 – May 2019

Portfolio

Abstract diagram in navy and blue: a table of rows above three chevrons flowing left to right, representing records moving through the stages of an ERP document flow.
2022 – Present

Maintainer and feature developer

A C# Web API and SQL Server 2008 ERP spanning Sales, Inventory, Procurement and Construction, maintained and extended alongside…

  • C# Web API (.NET)
  • SQL Server 2008
  • T-SQL
  • Angular
Abstract diagram in navy and blue: a browser window containing a wide hero block above three even columns, representing a marketing website layout.
2022

Built and delivered the site

The Myvan group's public-facing marketing site, built and delivered in WordPress. Listed because it is real delivered work, and…

  • WordPress

Multi-tenant Accounting & ERP Platform

Pilipinas Steel — Legacy ERP

Maintainer and feature developer · 2022 – Present
Abstract diagram in navy and blue: a table of rows above three chevrons flowing left to right, representing records moving through the stages of an ERP document flow.

A C# Web API and SQL Server 2008 ERP spanning Sales, Inventory, Procurement and Construction, maintained and extended alongside the newer platform.

  • T-SQL stored procedures for GL posting, reconciliations and reporting, engineered around what SQL Server 2008 does not have: no OFFSET/FETCH, no STRING_SPLIT, no JSON.
  • Query and stored-procedure tuning on the tables driving the SO→DR→SI sales flow and inventory costing, improving report and lookup responsiveness.
  • Subsidiary ledgers reconciled against control accounts to keep AR/AP and inventory balances accurate at period close.
  • Bill of Materials functionality for construction project costing.

Stack: C# Web API (.NET), SQL Server 2008, T-SQL, Angular

Paylalo — Company Website

Built and delivered the site · 2022
Abstract diagram in navy and blue: a browser window containing a wide hero block above three even columns, representing a marketing website layout.

The Myvan group's public-facing marketing site, built and delivered in WordPress.

Listed because it is real delivered work, and flagged for what it is: a marketing site, not the accounting platform above.

Stack: WordPress

John Bryan Logdonio in a dark suit, holding a laptop and pointing at an accounting ERP dashboard showing sales, expenses and cash-flow panels.
John Bryan Logdonio standing in a dark suit and tie with arms folded.

Education

Asian College of Technology

Bachelor of Science in Information Technology
major in Computer Programming

Working student

2015 – 2019

Skills

Languages & Tools
Frontend
  • Angular 19 — standalone components, signals, signal-based services
  • PrimeNG 19
  • TypeScript, RxJS
  • Responsive data-dense dashboards
  • Printable report layouts
Backend & APIs
  • C# / ASP.NET Web API (.NET)
  • Supabase Edge Functions
  • REST API design
  • Custom JWT auth with company/branch (multi-tenant) context switching
Databases
  • PostgreSQL — row-level security, RPCs, triggers
  • Supabase — Auth, Storage, Realtime
  • SQL Server 2008 — T-SQL, stored procedures, query and performance tuning
  • Legacy SQL workarounds for missing OFFSET/FETCH, STRING_SPLIT and JSON
Accounting & ERP Domain
  • Double-entry GL posting, AR/AP, subsidiary-vs-control reconciliation
  • Inventory & costing — WAC / moving-average / FIFO, stock cards
  • Procurement — PR→PO→RR, 3-way match, GRNI
  • Sales flow — SO→DR→SI
  • Construction project costing — percentage-of-completion, retention, progress billing
Philippine BIR Compliance
  • VAT and withholding tax / EWT
  • Official Receipt vs Sales Invoice
  • Books of accounts and audit trail
  • Period cut-off
Architecture
  • Multi-tenant SaaS with row-level security
  • Modular ERP design
  • Money-path logic in database RPCs / stored procedures
John Bryan Logdonio thinking, surrounded by the logos of the technologies he works with — Angular, TypeScript, C#, PostgreSQL, Docker, Git and others.
John Bryan Logdonio writing notes beside a laptop and a cup of coffee at a coffee shop table.

Blog

Movies

Spider-Man: Brand New Day — what a clean slate costs

Four years after the whole world forgot Peter Parker existed, the fourth MCU Spider-Man film asks what a hero is worth with no name, no history and no safety net. A spoiler-free look at what Brand New Day sets up, who it puts in the room, and why the numbers went the way they did.

Posting rules that survive a real close
Engineering Notes

Posting rules that survive a real close

Every accounting system posts to the general ledger. The ones that survive a month-end close are the ones that made posting a single, auditable path — not a helper each module calls its own way.

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