Portfolio / 2026
Edwin G. De Jesús
Senior Software Engineer
I design, build, and ship complete business applications, from the database and API to the pixel, and I modernize the legacy systems nobody else wants to touch.
AI engineering, daily practice
Selected work
Real systems, rebuilt here as living demos
These are white-labeled recreations of production software I built and shipped for internal business teams. The originals run behind company walls, so each card carries a faithful, interactive miniature instead of a screenshot. Each demo is a deliberately small-scale sketch of its system's signature screen, not a 1:1 copy; the production builds carry the full data models, auth, integrations, and edge cases.
01Enterprise reporting
Vendor Price-Adjustment Platform
Replaced a manual spreadsheet workflow for a retail purchasing department with a full-stack reporting platform: type a vendor number, get an approval-ready, print-perfect report in seconds.
- .NET 8 backend in clean architecture with API, Application, Domain, and Infrastructure layers
- Pixel-accurate print pipeline: CSS @page rules, repeating table headers, signature blocks
- Sortable columns, KPI summary cards, recent-lookup memory, skeleton loading states
| Item | Description | Cost | Adj |
|---|---|---|---|
| 104412 | Espresso Roast 12oz | $8.40 | +4.2% |
| 208831 | Olive Oil 500ml | $11.90 | -2.1% |
| 331245 | Basmati Rice 5lb | $9.75 | +1.8% |
| 447210 | Almond Milk 1L | $3.15 | +6.5% |
| 552087 | Dark Chocolate 85% | $4.60 | -1.4% |
Click a column header to sort. Tri-state, just like the real report.
02Operations dashboards
Work-Order & Ticketing System
An engineering department’s helpdesk: notifications flow through approval into work orders with technician assignment, purchase authorizations, and a live operational dashboard.
- KPI cards that drill into pre-filtered views; donut and multi-year trend charts
- Role-based access with per-department data visibility
- Real-time refresh so the dashboard reflects the floor, not last hour’s export
- Notifications14
- Work orders8
- Scheduled5
- Closed (month)23
Hover a segment and the center readout follows, like the production dashboard.
03Logistics & real-time data
Import Logistics Tracker
Tracks ocean freight from supplier ETD to warehouse receipt. Surfaces the expensive question early: which containers are sitting at port accruing demurrage right now?
- Live KPI tiles with count-up telemetry and click-through detail drawers
- Threshold-based severity badges turn a data table into an action list
- Paste-from-spreadsheet ingestion parser for zero-friction data entry
04Customer analytics & marketing
Loyalty Program Analytics & Campaigns
Turns a retail loyalty program’s raw transaction stream into decisions: who is enrolled, who is drifting away, what they buy, plus a campaign builder to reach exactly that segment by email.
- .NET clean-architecture API aggregating member, transaction, and sales data
- Segment-targeted campaign composer with audience sizing and email banner preview
- Member profiles with transaction history, favorites, and one-click Excel export
05Workflow & compliance
Purchase-Order Portal
A bilingual procurement portal covering the entire PO lifecycle: creation, budget checks, multi-step approval, digital signature capture, PDF generation, and a searchable audit log.
- Canvas signature pad with review/feedback loop between requester and approver
- Generated PDFs match the company’s legacy paper forms line-for-line
- Department budget guardrails block overspend before it happens
The real portal adds signature capture, audit log, and budget guardrails per department.
06E-commerce platform
Supply Storefront
A complete e-commerce build serving as an internal storefront: department heads and office admins browse a searchable catalog, fill carts against their monthly budgets, and check out into an approval and fulfillment pipeline. Swap the catalog and the payment step and the same platform runs a customer-facing shop.
- Full storefront stack: catalog with search and filters, cart, checkout, order history
- Budget guardrails size every cart in real time before checkout
- Order lifecycle with live SignalR updates, signature on receipt, and printable order sheets
07Legacy modernization
Employee Self-Service Portal
A 2003-era VB.NET WebForms intranet where hundreds of employees check pay stubs and HR documents. Rather than a risky rewrite, I modernized it in place: a redesigned responsive home, cleaned-up encoding and markup, and the same battle-tested backend underneath.
- Incremental modernization with zero downtime for a system in daily use
- Redesigned portal home: searchable directory of 40+ internal apps, quick-access tiles, announcements, and a guided page tour
- Careful staged rollouts with full backups at every step of the rework
Welcome to the App PortalA. Rivera, Store #14
9:41 AMWeb applications
08Gaming systems
Slot Gaming Engine (RGS)
A remote gaming server and slot frontend, built the way real casinos do it: the Laravel RGS owns the odds, computing every spin outcome server-side against configurable paytables and a progressive jackpot, while the React client only renders results. Try a few spins below.
- Server-authoritative outcomes: the client cannot influence or predict a spin
- Configurable paytables, progressive jackpot accrual, and player wallet sessions
- Token-authenticated REST API between the game client and the RGS
Server-authoritative spins. Fun-play odds in this demo.
In production the Laravel RGS computes every outcome server-side with regulated paytables. Demo odds are boosted so you can see the fireworks.
09Offline-first & distributed
Live Event Voting System
A kiosk voting platform for live costume contests: multiple voting stations on an ad-hoc LAN with automatic peer discovery, running fully offline on show day with no venue Wi-Fi required.
- Electron + React 19 desktop build, distributed on USB with a one-click launcher
- LAN multiplayer via mDNS auto-discovery and a compact binary message protocol
- Device fingerprinting for one-vote integrity; bilingual UI; PDF results export
Tap your favorite contestant
Capabilities
The toolbox
Eight-plus years of shipping across every layer of this list, from Power BI models and legacy VB.NET to React 19 and multi-agent AI systems.
Frontend
Backend
Data & Reporting
Cloud & Ops
AI & Agents
Practices
Highlights
Numbers I stand behind
Diagnosed a zero-delay polling loop in a digital-signage platform doing 43M requests/day and shipped the fix: enforced minimums, exponential backoff, smart stop.
Owned end-to-end for purchasing, engineering, logistics, and supply teams: requirements, data model, API, UI, deployment, and the training docs.
The voting platform ran a real contest on an isolated LAN: kiosks self-discovered, tallies synced, results printed. Offline-first is a design choice, not a fallback.
Off the clock
R&D and personal platforms
The work above pays the bills; this is where I push on what's next: AI tooling, agent orchestration, and local-first product design.
AI tooling
Natural-language video editing
An MCP server that gives AI assistants hands-on control of a professional video editor: cuts, transitions, overlays, clip speed, and transcription, all driven through the Model Context Protocol.
Product design
Local-first writing studio
A creative writing studio built for a novelist: chapters, outlines, and world notes that never leave the device. Designed end-to-end, including the illustration-grade UI, for a very demanding client (my wife).
In progress
Currently building
A private dual-AI orchestration platform where two coding agents collaborate under director control, with verified completion and a full flight recorder.