About Ustym Kushnir
Senior full-stack developer with 10+ years shipping custom software for service businesses. Working remotely from Mykolaiv, Ukraine, with clients across Argentina, Mexico, Brazil, Spain, Ecuador, Italy, USA and Colombia.
The approach
Every project starts from what the business is losing today, not from a feature list. The right question is never “what does the app do”, it is “what would the business look like if this one specific bottleneck were solved”.
Everything ships as code the client owns, on infrastructure the client controls. Never a rented SaaS, never a lock-in stack. The repository is transferred at delivery, the database lives on the client's own DigitalOcean droplet, the API keys are in the client's own accounts.
Every deliverable arrives with a 60-day warranty on behavioral defects and a written scope of what is in and out. There are no upsell menus. The proposal is the agreement.
Numbers
5.00
Workana rating
50+
Rated projects
11+
Repeat clients
10+
Years shipping
Experience
Full-Stack Developer
MintyMint · Kyiv, Ukraine
- · Built custom applications and automation for companies whose manual processes had stopped scaling.
- · Replaced spreadsheet and paper workflows with systems the team stopped having to think about.
- · Delivered multi-tenant SaaS platforms with subscription billing and per-client data isolation.
- · Worked directly with owners and operations leads, not only with technical teams.
- · Kept every project on stacks the client could own and hand to anyone later.
Blockchain & Smart Contract Developer
Self-Employed · Remote
- · Launched the Vetra (VTR) stablecoin on Polygon PoS, with Chainlink Functions verifying reserves in real time.
- · Deployed ERC-20 tokens and smart contracts for fintech and SaaS clients moving real value.
- · Treated security as a design decision, with role-based access, pausable contracts and a full on-chain audit trail.
Services offered
Custom Booking & Scheduling System Development
Own the appointment engine your business already runs on.
Operations Automation — Replace Spreadsheets, Paper and Manual Workflows
Software the team stops having to think about.
AI CRM & WhatsApp Assistant Development
AI put inside the process that already runs, not on top of it.
Blockchain & Smart Contract Development
Real tokens, real reserves, real audit trail — no vaporware.
Security Engineering & Incident Response
Get the attacker out, then make getting back in expensive.
Fintech & Payment System Integration
Money moves correctly, or it does not move at all.
Mobile App Development — iOS, Android, Cross-Platform
Ship to the App Store and Google Play, without the SaaS wrapper tax.
Ready to talk?
Send a written brief with the business problem to solve. I come back with a concrete plan against that document.
Contact →