2 of 4 Q1 spots filled · booking now

Senior Engineer
Who WillBuild
Your Software.

Senior full-stack engineer based in Connecticut. Amazon alum. 100+ websites built, 50+ apps shipped to the App Store and Google Play. If it runs on code, I can build it, fix it, or ship it.

>_Start Your Project Bounced from the App Store?

Available nowReply < 6 hrsConnecticut, USA

[ 01 ]

Amazonalumni

Senior engineering background

[ 02 ]

+ websites

Shipped solo, end-to-end

[ 03 ]

+ apps live

App Store + Google Play

[ 04 ]

hr reply

Every business day

App StoreGoogle PlayTestFlightReactNext.jsSwiftiOSwatchOSAndroidCapacitorCloudflare WorkersVercelStripeOpenAIAnthropicGroqSupabasePostgresCursorLovableBoltv0Replit

Built on · Distributed via

App Store
Approved appeals
Google Play
Direct submissions
Cloudflare
Workers · Pages · D1
OpenAI · Anthropic
Production-grounded AI

[ Recent Work ]

Real apps, real shipping

A few of the products built and shipped solo. Live on the App Store, Google Play, and the open web.

AI App Builder · BYOK

AIVibesdk

AIWebPad · agent inbox

WebWorkers

Public Secrets

iOSApp Store

Support Bears

iOS

Superclaw — Marketing

Web

Superclaw Hub

WebSaaS

Superclaw Chat

Web

Superclaw Hub Landing

Web

Model Surgery

AIWeb

Public Secrets — Brand

Brand

AI App Builder · BYOK

AIVibesdk

AIWebPad · agent inbox

WebWorkers

Public Secrets

iOSApp Store

Support Bears

iOS

Superclaw — Marketing

Web

Superclaw Hub

WebSaaS

Superclaw Chat

Web

Superclaw Hub Landing

Web

Model Surgery

AIWeb

Public Secrets — Brand

Brand

AI App Builder · BYOK

AIVibesdk

AIWebPad · agent inbox

WebWorkers

Public Secrets

iOSApp Store

Support Bears

iOS

Superclaw — Marketing

Web

Superclaw Hub

WebSaaS

Superclaw Chat

Web

Superclaw Hub Landing

Web

Model Surgery

AIWeb

Public Secrets — Brand

Brand

AI App Builder · BYOK

AIVibesdk

AIWebPad · agent inbox

WebWorkers

Public Secrets

iOSApp Store

Support Bears

iOS

Superclaw — Marketing

Web

Superclaw Hub

WebSaaS

Superclaw Chat

Web

Superclaw Hub Landing

Web

Model Surgery

AIWeb

Public Secrets — Brand

Brand

swipe

[ What I Do ]

I Handle Everything End-to-End

I'm Daniel Castellani, a senior full-stack engineer based in Connecticut. I ship production software solo — no agencies, no contractors, no offshore handoffs. Whether you need something built from scratch, rescued from a stuck project, fixed after another developer gave up, or published to the App Store, I handle the entire stack.

publishd@build:~

Build

Apps, websites, SaaS products, and AI tools

utils.ts

import { useState, useEffect } from 'react';

import { cn } from '@/lib/utils';

export function useCounter() {

- const [count, setCount] = useState(0);

- useEffect(() => {

- console.log(count);

- }, [count]);

+ const [count, setCount] = useState(0);

+ useEffect(() => {

+ console.log('Count changed:', count);

+ }, [count]);

return { count, setCount };

}

Apply suggestion

Fix

Broken apps, websites, APIs, and backend systems

mainbroken

feature/paymentsabandoned

rescue/by-danielshipping

Rescue

Stuck or abandoned projects, taken over and shipped

$publishd ship

Building production bundle...

Resolving deltas: 100% (1234/1234), done.

Provisioning Cloudflare Worker...

Wiring DNS + edge cache...

Live in production

Publish

Apps to the App Store and Google Play, end-to-end

AI

Custom AI integrations into existing products

Stripe

Cloudflare

Supabase

Resend

Vercel

GitHub

Automate

Workflows and business processes

[ Services ]

Five Ways I Work With Founders

Build My App / Website / Software

Full-stack development for mobile apps, web apps, SaaS, dashboards, and prototypes. I turn ideas into production-ready products.

From $1,499 flat · 14–21 days typical

Fix My App / Fix My Website

Bug fixing, crash resolution, performance improvements, backend repairs, and emergency engineering support.

Diagnostic call $299 · Fix scoped per project

App Publishing & App Store Submission

I handle App Store and Google Play submissions, metadata, screenshots, compliance, and rejection fixes.

From $399 flat · 7–14 days · Includes Guideline 4.2 appeals

AI App & Automation Development

Custom AI tools, agents, workflows, and integrations for apps and businesses.

From $399 + hosting · Deployed in under two weeks

Project Rescue & Engineering Support

If your developer disappeared, your project is stuck, or your app is broken, I step in and get it shipped.

Scoped after a 30-min audit call · No retainer

[ How It Works ]

How Working With Me Works

No discovery call. No agency handoffs. No retainers. You write a kickoff, I quote a flat fee, you ship.

Tell me what you need built or fixed

Three-minute kickoff form, or email me directly. No discovery call required.

I review and reply with a clear plan

Reply within 6 business hours with scope, timeline, and a flat fee. No retainers.

I build, fix, or publish your product

Days, not months. Ship target locked at the quote stage. You see progress as it happens.

You ship it — fast, clean, production-ready

You own the code, accounts, and domain. I'm removed once the project is live.

[ Why Hire Me ]

Why Founders Hire Me

8+ years shipping production software

Amazon alumni, now solo since 2024

Reply within 6 business hours

Often under 4. You get my direct number day one.

Apple Guideline 4.2 specialist

Fixed apps other devs declared dead.

Full-stack across mobile + web

React, Swift, watchOS, iOS, Android, Node, Python, AI/LLM

Connecticut-based, global clients

Strong overlap with US, UK, EU business hours.

One contact point

Direct line to me, never a project manager or ticket queue.

[ Testimonials ]

What founders say after shipping with me

Real reviews from real clients. Sourced from Google and Trustpilot — verified, not curated quotes.

4.8avg · 12+ reviews

Google verified

Daniel led me through the process of creating a new site for my organizing business with incredible skill and patience. The aesthetic quality truly exceeded my expectations — a beautiful site, with great functionality, at an amazing price. I would hire him again in a heartbeat.

Suzan LegmanOrganizing business owner

Google verified

Daniel has always been very responsive to my business needs. He provides excellent service and will spend the time to discuss options and ideas.

Brickman Law OfficeLaw firm

Google verified

Working with Daniel is always a pleasure. He did a great job on my website — along with his creativity and professionalism I got the results I was looking for. Highly recommend.

Josi UnderhillWeb design client

Google verified

Worked out well — great designer. Built me a full licensing software for my product. Insane.

Jesse FinnickProduct owner

Trustpilot verified

Was great. I'm a local business and dealt with him in person. Thanks.

Kimberly WilsonLocal business

Flat Fees. No Subscriptions. No Surprises.

Every project is one flat fee, scoped before you pay. Apple Developer ($99/yr) and Google Play ($25 one-time) fees are paid directly to the platforms.

AI Removal

Vibe-coded site that screams Lovable / Bolt / v0? I refactor it to read like a human built it. Audit + rewrite + diff back to you.

$99flat

48–72 hr · refactor + audit report

De-AI my site

Rejection Rescue

Bounced from the App Store? I write the appeal, fix the cited issues, resubmit.

$199flat

Apple Guideline 4.2 specialist

Get me approved

Single Platform

Existing app to iOS OR Android — submission, metadata, screenshots, store listing.

$200flat

7–10 days

Submit my app

Coaching

Architecture review, rejection strategy, stack decisions. I teach you, you ship.

$299/ 90 min

Live call · screen-shared

Book a call

Both Platforms

Existing app to App Store + Google Play. Icons, screenshots, metadata, rejection appeals.

$399flat

Done For You Premium

Expedited end-to-end submission with priority support, rejection handling, and 60-day post-ship coverage.

$699flat

Premium · expedited

Get expedited

Studio & Custom Builds

Need a custom website, web app, SaaS, or full native build? Full tier table with timelines and add-ons.

See pricing

Studio tier starts at $2,999

View all pricing

Apple Developer $99/yr · Google Play $25 one-time · paid directly to platforms

[ App Publishing ]

Ship Your Web App to the App Store and Google Play

I handle App Store and Google Play submissions end-to-end — metadata, screenshots, policies, and rejection appeals. Apple rejects roughly 30% of first submissions, often citing Guideline 4.2 ("insufficient native functionality"). I've shipped apps from Lovable, Bolt, v0, Cursor, Replit, React Native, Flutter, and Capacitor. If your app keeps getting rejected, I can fix it and get it approved — rejection handling is included.

Fix My App Store Rejection

App Store + Google Play submission
Metadata, screenshots, policy review
Guideline 4.2 appeal writing
Rejection handling included

[ AI Development ]

Build AI Tools, Agents, and Automations

I build custom AI apps, integrate AI into existing products, and create automations that save time and money. Deployed on cost-efficient infra (Cloudflare Workers, Vercel, Railway) in under two weeks. Trained on your real business content, not generic models.

9:41Publishd AI

youWhat do you build?

publishdApps, sites, and AI tools — flat fees, shipped solo. Ask pricing or timelines anytime.

Same bot as the header · loads only when opened

Live assistant on demand

Streaming, on-brand, deployed to your domain.

Bring-your-own-key (OpenAI, Anthropic, Groq, or local) — same experience as the help bot (chat icon in the nav or the button in the preview). I wire it into your existing site, your data, your tone of voice. No subscription, you own the code.

AI agents
AI chat tools
AI workflow automation
AI-powered apps
AI integrations for existing software

Build my AI tool

[ FAQ ]

Frequently Asked Questions

[ Start your project ]

Real human reply in under 6 hours.

One builder, not a team. Tell me what you need.

>_Full project intake Email Daniel

[ Built by Daniel Castellani ]

Code that compiles.
Apps that ship.
Bills that don't surprise.

Connecticut-based senior engineer. Worldwide clients. One contact, one flat fee, one ship date — no agencies, no offshore handoffs, no monthly retainers.

>_Start a project daniel@publishd.app

rendering · livescene · publishd-cube-v1

Q1 bookingReply < 6 hrs · flat feesStart

Senior Engineer Who WillBuildYour Software.

Trust signals — proof of solo senior delivery

Real apps, real shippingreal shipping

I Handle Everything End-to-EndEnd-to-End

Build

Fix

Rescue

Publish

AI

Automate

Five Ways I Work With Founders

Build My App / Website / Software

Fix My App / Fix My Website

App Publishing & App Store Submission

AI App & Automation Development

Project Rescue & Engineering Support

How Working With MeWorking With Me Works

Tell me what you need built or fixed

I review and reply with a clear plan

I build, fix, or publish your product

You ship it — fast, clean, production-ready

Why Founders Hire Me

8+ years shipping production software

Reply within 6 business hours

Apple Guideline 4.2 specialist

Full-stack across mobile + web

Connecticut-based, global clients

One contact point

What founders say after shipping with meshipping with me

Flat Fees.Flat Fees. No Subscriptions. No Surprises.

AI Removal

Rejection Rescue

Single Platform

Coaching

Both Platforms

Done For You Premium

Studio & Custom Builds

Ship Your Web App to the App Store and Google Play

Build AI Tools, Agents, and AutomationsAI Tools, Agents, and Automations

Streaming, on-brand, deployed to your domain.

Frequently Asked Questions

01How do I hire a senior engineer to build my app?

02Can you fix a broken app or website that another developer abandoned?

03How much does it cost to publish a web app to the App Store and Google Play?

04Can you ship apps built with Lovable, Bolt, v0, or Cursor?

05What if Apple rejects my app for Guideline 4.2?

06How long does a typical project take?

07Do I own the code, accounts, and domain?

08Are you an agency or a solo engineer?

09Where are you based and what time zones do you cover?

Real human reply in under 6 hours.6 hours.

CodeCode that compiles. AppsApps that ship. BillsBills that don't surprise.

Senior Engineer
Who WillBuild
Your Software.

Real apps, real shipping

I Handle Everything End-to-End

How Working With Me Works

What founders say after shipping with me

Flat Fees. No Subscriptions. No Surprises.

Build AI Tools, Agents, and Automations

Real human reply in under 6 hours.

Code that compiles.
Apps that ship.
Bills that don't surprise.