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XonkelX/README.md

Oniel Alejo Feliz — Full-Stack Developer

Visit Oniel's portfolio Email Oniel View Oniel's projects

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


👨‍💻 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
614
Documented release checks
Full stack
UI to database
Open to work
Tampa / Remote

🚀 Featured engineering work

Relay — Reliable Webhook Delivery

A production webhook delivery platform with durable scheduling, signed requests, deterministic retries, operational evidence, and a public failure laboratory.

Failure Lab 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

Completed contributions currently under maintainer review.

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

Maka Agent — 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, surfaced a bounded diagnostic, and kept configuration removal responsive
  • Added a regression fixture covering the hostile notification pattern; all 58 MCP workspace tests pass locally

TypeScript · Node.js · MCP · npm

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 locally across both browser profiles

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

🧰 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

📊 GitHub activity

Oniel's GitHub statistics Languages used across Oniel's public repositories

🧭 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 looking for a junior full-stack or software-developer role where I can contribute dependable engineering, grow with an experienced team, and help ship thoughtful products.

Contact Oniel about an opportunity

Pinned Loading

  1. CareerFlow CareerFlow Public

    A production-ready career-management platform for tracking applications, deadlines, progress, and resume versions.

    TypeScript

  2. next-queue next-queue Public

    Production-ready real-time queue system built with Next.js, Supabase, PostgreSQL, Realtime, and database-enforced authorization.

    TypeScript

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

    TypeScript