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You will get Fullstack MERN Developer for your project | Fullstack MERN Developer

Sergey E.Status: Offline
Sergey E. Sergey E.
Rising Talent
Preview image

Let a pro handle the details

Buy Custom Website Programming services from Sergey, priced and ready to go.
Sergey E.Status: Offline
Sergey E. Sergey E.
Rising Talent
Preview image

Let a pro handle the details

Buy Custom Website Programming services from Sergey, priced and ready to go.

Project details

❗𝐁𝐄𝐅𝐎𝐑𝐄 𝐁𝐔𝐘𝐈𝐍𝐆 𝐓𝐇𝐈𝐒 𝐏𝐑𝐎𝐉𝐄𝐂𝐓❗
Please contact me using direct messages before ordering, so I can understand your needs and requirements.

My tech stack: React, Next.js, Node.js, Python, ExpressJS, MongoDB, React Native

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Programming Languages
HTML & CSS, JavaScript, TypeScript
What's included
Service Tiers Starter
$30
Standard
$240
Advanced
$1,200
Delivery Time 2 days 7 days 14 days
Number of Revisions
000
Design Customization
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Content Upload
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Responsive Design
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Source Code
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Sergey E.Status: Offline

About Sergey

Sergey E.Status: Offline
MERN Stack Developer | SaaS Developer | MERN Developer MVP Development
Kharkiv, Ukraine - 1:16 am local time
MERN stack developer and SaaS developer. 19+ years hands-on, 20,000+ coding hours. Platforms I build hold ~800K users, sell 1M+ tickets a year and processed $41.7M in five months of 2026.

Most people reach me in one of three spots. Idea and deadline, no code yet, MVP development starting at zero. Product live but stalled, releases slipping month after month. Or a build inherited from a developer who left, and nobody can say what half of it does.

WHAT YOU GET
✔️ Software that holds up under load. 99.9% uptime across 1,000+ live events a season, 98.47% card success on 673K payments.
✔️ One contract for the whole build. 36 people across dev, PM, BA, QA, DevOps and design. No two vendors blaming each other.
✔️ An MVP that reaches paying users. A subscription SaaS I develop end to end grew MRR 2.4x in 15 months.
✔️ Code you can still hire against in year ten. As a MERN developer I've run multi-tenant SaaS in production 10+ years. Average client stays 7.8 years, longest is 15.
✔️ AI integration already in production. OTTO PILOT is in beta with live clubs, on accounts worth up to $5M.

Send me what you're building and I'll reply with a scope estimate and the first technical decision I'd settle.

Sergey

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SPORTS AND EVENT SAAS, $41.7M PROCESSED IN 5 MONTHS
- MERN stack developer, SportWrench events: 15 events a season grown to 1,000+, 1M+ tickets a year, ~800K users.
- MERN developer, SportWrench payments: $23.1M in 90 days on 385,804 payments, 0.03% disputes.
- SaaS developer, SportWrench Stripe Connect: $41.4M in 5 months, $2.53M in one day at nationals.
- MERN stack developer, SportWrench live ops: 99.9% uptime over 1,000+ events a season, 1,000+ QR scans an hour at the gates.
- Node.js developer, SportWrench integrations: 400K+ emails a month, 20+ integrations.
- MERN developer, University Athlete: 15 years MVP to enterprise, 15M+ athlete activity rows.
- SaaS developer, University Athlete white-label for NCSA: 6-year deal, 200K+ tagged athletes.
- MERN stack developer, NFL FLAG platform: 750K+ participants, 24,000+ schools.
- Full stack developer, SportWrench ticketing: 2x to 3x growth in sales and event volume, 673K payments cleared.

STARTUP MVP AND SUBSCRIPTION SAAS, MRR 2.4x IN 15 MONTHS
- MVP development, University Athlete Club Account: soft launch to release series in 21 days, 2 releases a week, 4x daily logins.
- MERN stack developer, subscription SaaS end to end: MVP development to 2.4x MRR in 15 months, 80 to 194 subs.
- MVP developer, new University Athlete line: 104% of March target, 7,205 new customers.
- SaaS developer, sports-tech client platform: $1.7M added revenue in a quarter, 40 new clients.
- MVP development, legacy migration: 50 to 100 license packages per club.
- MVP development, agency record: 19+ years, 20,000+ coding hours.

WEB, 3.3M+ SESSIONS IN 5 MONTHS
- React developer, SportWrench web: 675K active users in 5 months, 11M page views.
- Next.js developer, SportWrench pages: 4.3M event views, 4.1M event searches.
- MERN stack developer, SportWrench organic: 1.5M organic sessions as top channel, 91,132 users in peak week.
- Full stack web developer, University Athlete web: 538K new users in 5 months against 277K in all of 2025.

MOBILE, 84.4% OF 838K ANNUAL USERS
- MERN stack developer, SportWrench mobile: 84.4% of 838K users on mobile, 654K on iOS.
- App developer, Action Clip in Swift and React Native: 8 years in market.
- Full stack MERN, University Athlete mobile: 62.7% on mobile, 166K on iOS.

AI INTEGRATION, 4 PRODUCTS IN ACTIVE BUILD
- AI integration, OTTO PILOT agent: 3 engineers, live-club beta, accounts up to $5M.
- SaaS developer, AI roadmap: 4 products in build, scheduling to evaluation AI.
- MERN developer, Action Clip Golf: MediaPipe pose detection in production.

DATA AND VARIANTS
- ExpressJS developer and MERN developer with MongoDB: 15M+ activity rows, 6.4M tag records, 385,804 payments.
- Fullstack developer, full-stack developer, fullstack web developer, full-stack web developer, fullstack MERN, full-stack MERN, frontend developer, front-end developer, backend developer, back-end developer, back end developer: 100,000+ engineering hours, 118K cross-platform sessions a year, 10+ years multi-tenant SaaS.
- MORE: web developer, software developer, MERN stack, React, API integration, app developer, MERN flutter, full stack developer MERN, react native MERN, full stack developer saas, SaaS mobile app, SaaS full stack, full stack ai saas developer, saas development, ai saas development, saas business development, full stack saasdeveloper ai agents, webflow developer saas, saas mvp, startup mvp, mobile app mvp, bubble mvp, SaaS marketing, pitch deck: 19+ years, 20+ integrations.

SKILLS: HTML, HTML5, CSS, CSS3, JavaScript, jQuery, PHP, WordPress, Angular, Python, git, Swift, MediaPipe, LLM agents, software design, software architecture & design, software development, agile software development, software debugging, software testing, desktop application.

Steps for completing your project

After purchasing the project, send requirements so Sergey can start the project.

Delivery time starts when Sergey receives requirements from you.

Sergey works on your project following the steps below.

Revisions may occur after the delivery date.

Development

Review the work, release payment, and leave feedback to Sergey.