FULL-STACK PRODUCT ENGINEER

I fix broken product flows and finish features that are stuck.

For React, Next.js, API, data, and integration work inside an existing product. You receive the implemented change, verification evidence, and a clear handoff.

Discuss the issue See delivery examples
WHAT YOU CAN HIRE ME FOR A defined product problem taken through implementation and verification.
Repair a broken flow
Reproduce · isolate · fix · retest
Finish a product feature
Frontend · API · data · integration
Connect external services
Auth · payments · CRM · webhooks
Ship with evidence
Acceptance checks · handoff · release notes

SELECTED WORK

Evidence you can inspect before starting a project.

Each example shows the problem, the work performed, and how the result was checked. Inspect the fictional investor-pack consistency audit.

01 / API AND DATA IMPLEMENTATION

AI API Gateway

Controlled model access with customer keys, credit accounting, and a complete usage record.

Architecture flow from customer API request through a FastAPI gateway, OpenAI, and PostgreSQL accounting

The engineering problem

A customer-facing AI endpoint needs more than a provider call. Access, account status, available credits, provider usage, and the final transaction must agree before the response is considered complete.

Implementation decisions

  • Issue customer keys once and store only their hash.
  • Reject inactive keys and suspended accounts before provider work.
  • Convert token usage into credits and record the transaction.
  • Keep the provider secret in environment configuration.

System

FastAPI · PostgreSQL / Supabase · OpenAI Responses API · Render

API and data integration

02 / INTERACTIVE PRODUCT IMPLEMENTATION

Planet Console

A local-first command center for reconciling many engineering task returns without removing the human decision point.

Planet Console desktop overview showing linked workflow clusters and operational state

The engineering problem

Batch task results can be matched, missing, blocked, or unsafe to continue. The interface has to preserve those distinctions and produce a useful next packet without silently executing work.

Implementation decisions

  • Model dispatch, return, reconciliation, and continuation as separate states.
  • Keep blocked and human-decision results out of automatic continuation.
  • Make complex workflow state readable across spatial and narrow layouts.
  • Verify visual changes with desktop and mobile evidence.

System

React 19 · TypeScript · React Three Fiber · Three.js · Vite

Product workflow and interface

03 / PAID ENGAGEMENT · CLIENT RATED 5.0

iOS Checkout QA

An end-to-end mobile test covering registration, identity fields, a sandbox card payment, and a concise evidence handoff.

The assignment

Run a real iPhone onboarding and checkout journey, complete the supplied sandbox payment path, and return enough detail for the product team to act on the result.

What was delivered

  • Completed registration and checkout on a physical iPhone.
  • Recorded two locale and form-behavior risks during the run.
  • Confirmed the sandbox transaction without using a real card.
  • Returned a structured completion and evidence report.

Coverage

iOS · onboarding · form validation · checkout · evidence reporting

Paid mobile QA delivery

04 / ENGINEERING DEMONSTRATION

Checkout Release Workspace

A small interactive model of the release question that matters: can the normal path and the failure path ship together?

BUILDRC-042

Critical paths

04tracked

Open blockers

01needs review

Release state

HOLDvalidation required

VERIFICATION PASS

Release checks

Ready to run
01Checkout completionPrimary transaction pathQueued
02Failure responseError remains visible and recoverableQueued
03Regression replayKnown broken path retestedQueued
04Handoff recordScope and residual risk capturedQueued
4 critical paths

ISSUE RECORD

One clear blocker

HOLD
BUG-184 / CHECKOUT

Invalid address should not advance the flow.

Expected: visible field feedback, no confirmation state, no duplicate request.

HANDOFF NOTE

Release only when the error path is verified in the same build.

What it demonstrates

The same canonical state drives blocker count, release decision, check results, and handoff text. A successful path cannot leave a contradictory hold state behind.

Boundary behavior

Valid, malformed, and duplicate inputs receive distinct terminal classifications and remain visible in the trace record.

System

Semantic HTML · CSS · Native JavaScript

Interactive reference implementation

CAPABILITIES

Choose the result you need.

02

Focused product repair

The affected React, Next.js, API, or data path fixed and checked against acceptance criteria.

03

Feature and integration delivery

A defined feature or connected-service workflow implemented inside the existing system.

DELIVERY

A clear path through ambiguous work.

  1. 01

    Inspect

    Read the current system and reproduce the affected workflow.

  2. 02

    Decide

    Identify the boundary that changes the outcome and define acceptance.

  3. 03

    Implement

    Make the focused change across the layers the result actually requires.

  4. 04

    Verify

    Check normal and failure paths, then return a release-ready handoff.

START WITH THE SYSTEM

Send the affected workflow and the result you expected.

I will review the problem and propose the smallest paid step that produces a useful result.

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