Software engineering & applied AI
Senior Full-Stack Developer
Agentic AI Engineer
I turn complex workflows into software people can rely on. From the first database table to the last detail on screen.
Den Jansen Flores
Senior full-stack developer and agentic AI engineer in Metro Manila. I build web platforms and AI workflows for teams in the Philippines and abroad, fromhealthcare operations tocourier logistics andAI-assisted analysis.
I follow the work before choosing the tools: who handles each record, what happens next, and where things get stuck. Then I own the build from the database to the screen.
We agree on scope before work starts. Updates come directly from me. If a feature adds cost without helping the business, I say so.
02 / Web applications
Operational web products running in production. A closer look at the software I build, the decisions behind it, and the work I own.
Free, project-led learning platform that teaches front-end development through small browser-based coding tasks, live previews and deterministic checks.
Clinic operations platform that brings doctor availability, appointment scheduling and patient records under one role-aware system.
Multi-tenant dental platform with isolated patient records, appointment scheduling, reminders and a branded subdomain for each clinic.
Logistics operations platform that follows a shipment through booking, dispatch, proof of delivery, COD remittance and invoicing.
Workforce platform combining GPS-verified clock-ins, threaded support tickets and role-specific dashboards for employees and managers.
AI-assisted data platform that normalises business uploads, constrains model output and returns a dashboard the application can trust.
Student assessment platform that explains career recommendations and gives administrators a separate view of institutional results.
Responsive resale storefront built around one-of-one inventory, visible garment condition and a shorter path from browsing to purchase.
1 of 8
03 / Mobile applications
Android and iOS apps written with React Native and Expo, and with Flutter and Dart. Real camera work, on-device storage and behaviour that survives a dead signal.
Android and iOS study app where notes become flashcards, reviews are scheduled by a spaced repetition system, and everything works with the phone offline.
Flutter field guide that turns a phone camera into a way to identify plants, animals and everyday objects, then keeps every scan in a local discovery journal.
1 of 2
04 / Applied intelligence
AI agents with a job to do. Explore the interfaces, try the workflows, and see where human approval stays in control.
Sales and marketing operations
Mara researches prospects, keeps evidence beside each lead, prepares outreach for review and pauses follow-up when someone replies.
Interactive demo · Fictional data
Private AI secretary
Alfred combines a daily briefing, local file search and guarded actions with calendar and mail tools in a private assistant.
Hotel reception prototype
A hotel reception prototype checks fictional reservation and room state, answers common requests and holds consequential changes for a manager.
Interactive demo · Fictional data
1 of 3 · Mara
Built for useful work. Designed for human oversight.
All agent projectsOne owner across the interface, backend and AI workflow. Explore the services, then inspect the work behind each capability.
Complete web systems, from PostgreSQL schemas and access rules to server logic and the React or Next.js interface.
Explore serviceScheduling, dispatch, records and workforce platforms with multi-tenant architecture and role-based access control.
Explore serviceCross-platform apps built with React Native and Expo, or with Flutter and Dart, including on-device storage, camera pipelines and offline behaviour.
Explore serviceApplications where models call typed tools, return schema-validated output and carry state through guarded, multi-step workflows.
Explore serviceIngestion, normalisation and validation pipelines that feed dependable analysis and reporting surfaces.
Explore serviceEvery listed skill includes its context. Claims without a public example are marked.
Domain modelling
Appointment lifecycles, shipment states and ticket threads mapped from the operation itself.
Multi-tenant architecture
Per-practice isolation with subdomain routing.
Role-based access control
Role-separated portals where every user can reach only the records their role allows.
Operational workflow design
Scheduling and availability, dispatch and COD reconciliation, GPS-verified clock-in.
PostgreSQL
Relational models behind scheduling, dispatch and ticket lifecycles.
Supabase auth and row-level security
Sessions, tenant boundaries and row-level policies protecting deployed systems.
Next.js server routes
The server half of five deployed SaaS builds.
Node.js and Express
The API layer behind the student assessment platform.
MongoDB
Document storage where the assessment shape changes between cohorts.
Data ingestion pipelines
Uploads are normalised and validated before the analysis stage sees them.
React
Component systems across five deployed applications.
TypeScript
Typed contracts across the interface, data layer and API boundary.
Next.js
Six deployed applications, server and client boundaries included.
Tailwind CSS
Token-driven interface systems, including the one you are reading.
Accessible interface patterns
Keyboard navigation, native disclosures, semantic landmarks and tested contrast on this site.
React Native and Expo
A study app for Android and iOS: Expo Router navigation, NativeWind interface system and a release pipeline that runs type checks, tests, Expo Doctor and clean platform exports.
Flutter and Dart
A camera field guide for Android and iOS with Riverpod state, go_router navigation, light and dark themes and platform text-to-speech narration.
Offline-first mobile storage
A local SQLite schema with versioned migrations, so notes, cards and review history survive without an account or a network.
Device camera and media pipelines
Capture, gallery import, tap-to-focus and flash, with file type, size, orientation, resize and blur checks before a photo leaves the phone.
Mobile release engineering
EAS build profiles, store listing assets and a documented Google Play submission and rollback procedure. Neither app is published yet, so store release stays unproven here.
OpenAI API
The analysis stage of the ingestion pipeline.
Structured model output
Schema-constrained responses the interface can render without interpretation.
Prompt orchestration
Prepared context, explicit output shapes and iteration against observed failures.
Claude API and tool use
Used in client and internal work. The evidence sits outside this portfolio, so the capability remains unverified here.
Vercel deployment
Six live deployments, each linked and status-checked on its project page.
Public repositories
Six builds have public source. The private repository is labelled without ambiguity.
Astro static delivery
Core portfolio pages ship as static Astro HTML without hydration. The separate hotel front desk demo is a React static bundle.
Deployment verification
Every deployment link is opened, checked and dated before its status is published.
Understand the operation. Make the rules clear. Test what happens when things go wrong.
The workflow writes the schema.
A clinic appointment and a courier shipment obey different rules. I trace the real process first, then choose the tools. It costs more attention in week one and prevents a careless rebuild in month six.
One appointment row with explicit status transitions in ClinicFlow. A shipment lifecycle with proof of delivery and cash reconciliation in Biyahero Express.
Responsibility runs from schema to interface.
I write the data model, server logic, access rules and interface. I also answer for how they behave together. When a system fails at two in the morning, the handoff chart is irrelevant. Ownership is not.
Every project here was built end to end. Each project page lists exactly which parts, so the claim can be checked instead of believed.
A missed interface check should never become a disclosure.
The database enforces row-level policies and tenant boundaries. A conditional in a component may improve the interface, but it does not decide who can read a record. That decision belongs at the boundary an attacker cannot skip.
Row-level security across role-separated portals in ClinicFlow. Per-practice isolation with subdomain routing in Smiley.
Prepared context in. Validated output out. Cost known.
The model call is one stage. The surrounding code decides what context it receives, which tools it may use, what shape it must return and how the system recovers when it fails. Intelligence without control is still a liability.
The ingestion and analysis pipeline in the SaaS Data Analysis Platform: normalise, prompt, validate the shape, then render.
Every state needs a name, a transition and a way back.
Operational software fails at the edges: a double booking, a delivery completed twice, cash that never reconciles. I design those paths before the demo. The edge cases are where a system reveals what it was built to survive.
Booked, confirmed, completed and cancelled as states on one appointment row. Ticket lifecycles with threaded history in ShiftDesk.
The data, access and AI decisions behind the published work.
Independent and client work. Each case study names my contribution.
Deployment links checked . Career Path is no longer hosted.
A few things worth knowing about working together.
Have something else in mind?Jansen Flores is Den Jansen Flores, a senior full-stack developer and agentic AI engineer based in Muntinlupa City, Metro Manila. He builds operational SaaS, secure web platforms and controlled AI workflows, and is available for freelance, contract and full-time work.
Den Jansen Flores is a senior full-stack developer and agentic AI engineer in Metro Manila, Philippines. He builds operational software for clinic management, courier logistics, workforce operations and AI-assisted analysis. He owns the chain from schema to interface because weak handoffs become production failures.
His core stack is React, Next.js and TypeScript on the front end, with Supabase, PostgreSQL and Node.js behind it. He uses Tailwind CSS for interface systems. On mobile he builds for Android and iOS with React Native and Expo, and with Flutter and Dart. His AI work uses OpenAI and Claude APIs with tool calling, retrieval and schema-constrained output rather than a chat box added at the end.
Agentic AI engineering means a model does accountable work inside an application. It calls typed tools, retrieves grounded context, returns schema-validated output and carries state across several steps. The serious work is the control around the model: permissions, failure handling, observability and cost per run.
He is open to senior full-stack, product engineering and AI engineering roles. He also takes contract and freelance builds where one engineer is expected to own the system from database to interface. Full-time employment and fixed-scope work are both in range.
Yes. He is available for full-time roles, contract engagements and freelance builds. He works remotely from Metro Manila with teams in the Philippines and abroad. Email floresjansen28@gmail.com. Replies usually arrive within one business day on UTC+8.
His documented work covers education technology, healthcare operations, dental practice management, courier dispatch, workforce systems, e-commerce and AI-assisted business intelligence. Each sector links to a case study with the problem, architecture, ownership, source status and deployment status stated plainly.
The rules are set before the build begins. He traces the real workflow before choosing the framework, keeps access rules close to the data and names the failure paths before launch. Updates come directly from him. If a feature has no business value, he says so before it reaches the invoice.
Every project page links to its deployment and, when public, its source repository. Private source is labelled private, and offline deployments are labelled offline. Each case study carries the date when its deployment status was last checked.
The portfolio is published at denforge.it.com, under the DenForge name. That is the canonical address for every case study, service page and machine-readable feed. The earlier address, jansen-dev.vercel.app, now redirects there permanently and should no longer be cited.
He is based in Muntinlupa City, Metro Manila, Philippines, on UTC+8. He works remotely, covers Asia-Pacific business hours and can schedule early or late calls for European and North American teams when the work requires it.
A new product, a difficult workflow, or a system ready for its next chapter. Tell me what you have in mind.
Usually replies within one business day.
UTC+8
Full-time roles, contract work, and freelance builds