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XonkelX/README.md

Oniel Alejo Feliz — Full-Stack Developer

Visit Oniel's portfolio Email Oniel Connect with Oniel on LinkedIn View Oniel's projects

Available for full-stack and software-engineering opportunities
Building dependable products from accessible interfaces to secure data architecture.

Animated terminal showing Oniel Alejo Feliz's GitHub activity and full-stack engineering toolkit


👨‍💻 Professional profile

I am a full-stack developer in Tampa, Florida who turns product ideas into complete, deployed web applications. I work across responsive React interfaces, authentication, relational data modeling, authorization, automated testing, documentation, and production delivery.

My portfolio demonstrates more than screens: it shows how I reason about reliability, data ownership, privacy, accessibility, concurrency, real-time synchronization, and operational constraints.

4
Deployed products
4
Merged upstream PRs
Full stack
UI to database
Open to work
Tampa / Remote

🚀 Featured engineering work

Relay — Reliable Webhook Delivery

A deployed webhook delivery portfolio release with durable scheduling, signed requests, deterministic retries, operational evidence, and a public failure laboratory.

Relay demo Release Source

  • Transactional outbox, D1-backed scheduling, Queue transport, lease recovery, and bounded at-least-once delivery
  • Standard Webhooks-compatible signatures, AES-GCM encrypted endpoint secrets, replay lineage, and redacted attempt evidence
  • 304 release checks plus a production flaky run proving HTTP 500 → 500 → 200 recovery with stable message identity

TypeScript · React · Cloudflare Workers · D1 · Queues · Hono · Vitest · Playwright

Next — Real-Time Queue System

A persistent, multi-client queue for customers, staff, and public displays, with authorization and state transitions enforced in PostgreSQL.

Live application Interactive demo Source

  • Database-enforced authorization with RLS, security-definer RPCs, and private/public data boundaries
  • Idempotent commands, transactional row locks, monotonic revisions, and multi-client Realtime convergence
  • 131 passing release checks across Vitest, pgTAP, integration, Playwright, and production smoke testing

Next.js · TypeScript · Supabase · PostgreSQL · Realtime · pgTAP · Playwright

CareerFlow — Career Management Platform

A privacy-conscious workspace for tracking applications, deadlines, status progress, dashboard insights, and resume versions.

Live application Release Source

  • Server-enforced ownership boundaries, Auth.js sessions, Argon2id credentials, and Zod validation
  • Searchable application workflows, deadline-aware dashboards, and versioned resume organization
  • 179 passing tests spanning unit, component, integration, and database-backed coverage

Next.js · React · TypeScript · PostgreSQL · Prisma · Auth.js · Vitest

Developer Portfolio

A typography-led portfolio that turns finished engineering work into accessible, recruiter-friendly case studies.

Visit portfolio Source

  • Responsive editorial presentation, dark/light themes, restrained motion, and reduced-motion support
  • Semantic structure, keyboard navigation, focus management, Playwright journeys, and axe checks

Next.js · React · TypeScript · Tailwind CSS · Motion · Playwright · axe-core

🤝 Open-source contributions

Contributions to established codebases, including four merged pull requests and one active review.

Clarvia — Accessible bereavement workflows

Pull request

  • Audited the checklist and contribution paths with keyboard navigation, axe-core, Chromium accessibility inspection, and NVDA
  • Fixed focus containment and restoration across the mobile drawer, cookie dialog, and checklist preview without changing the visual design
  • Added programmatic question labels, selected-state semantics, named inputs, and keyboard-operable result cards; upstream validation and security checks passed

Next.js · React · TypeScript · Accessibility · NVDA · axe-core

Reticle — Persistent learned routes

Pull request

  • Persisted routes learned from crawling and ordinary browser navigation as deterministic, duplicate-free project data
  • Preserved existing learned flows, run history, and absent-versus-empty semantics under concurrent updates
  • Added focused unit and E2E coverage; the complete upstream CI pipeline is passing

TypeScript · Node.js · Playwright · pnpm

Bluehex — Production-build browser testing

Pull request

  • Added Playwright coverage for production routes, responsive navigation, focus behavior, form submission, and structural accessibility
  • Configured desktop and mobile Chromium projects plus a standalone GitHub Actions workflow
  • Verified 18 end-to-end tests across both browser profiles and incorporated maintainer review before merge

Next.js · TypeScript · Playwright · axe-core · GitHub Actions

Apache Maka — Bounded MCP tool rediscovery

Pull request

  • Prevented an MCP server from causing an unbounded discovery loop by notifying after every tool-list response
  • Preserved the last callable tool snapshot while coalescing valid updates and keeping configuration removal responsive
  • Addressed adversarial review findings with delayed-response and notification-burst regressions before the upstream merge

TypeScript · Node.js · MCP · npm

FinVerify — Keyboard-accessible trust scores

Pull request

  • Turned visual confidence indicators into named ARIA meters with keyboard focus treatment
  • Replaced dense verification cards with a semantic table and strengthened accessible workspace coverage

React · TypeScript · Accessibility · axe-core

🧰 Engineering toolkit

Frontend

TypeScript React Next.js Tailwind CSS HTML5 CSS3

Backend & data

Node.js PostgreSQL Prisma Supabase Auth.js Cloudflare Workers Cloudflare D1

Testing & delivery

Vitest Playwright Docker GitHub Actions Vercel

🧭 How I build

  • Start with the decision a user needs to make, then design the smallest clear system around it.
  • Treat authorization, privacy, and ownership as architecture—not afterthoughts.
  • Validate behavior through automated tests, keyboard review, responsive QA, and production builds.
  • Document tradeoffs, limitations, setup, and release evidence honestly.

🤝 Let’s build something useful

I am open to full-stack and software-engineering roles where I can contribute dependable engineering, collaborate effectively, and help ship thoughtful products.

Contact Oniel about an opportunity

Pinned Loading

  1. CareerFlow CareerFlow Public

    Deployed career-management portfolio project for applications, deadlines, progress, and resume versions.

    TypeScript

  2. next-queue next-queue Public

    Deployed real-time queue portfolio project with Next.js, Supabase, PostgreSQL, Realtime, and database-enforced authorization.

    TypeScript

  3. relay-webhook-delivery relay-webhook-delivery Public

    Deployed webhook delivery portfolio release with durable retries, signed requests, encrypted secrets, and inspectable failure evidence.

    TypeScript

  4. apache/maka apache/maka Public

    Apache Maka (Incubating) is a local-first AI agent workspace. Model messages, tool calls, tool results, permission decisions, and termination events are recorded as an append-only log.

    TypeScript 2.2k 255

  5. reticlehq/reticle reticlehq/reticle Public

    AI agents can generate code, but they still struggle to understand what they build. Reticle gives them runtime perception of web & desktop applications.

    TypeScript 334 74

  6. codesydney/bluehex codesydney/bluehex Public

    Find and hire Claude practitioners. Anyone in the community can publish a profile; Bluehex verifies the credentials behind it.

    TypeScript 6