Yastremskyi

About

The person

Six years of backend work, most of it on systems where a wrong answer costs somebody money.

Career

Where the work happened

Employers are named. Clients are not — three of the four case studies sit under NDA, and none of them is tied to a period or a company here.

  1. Apr 2024Present

    Senior Backend Engineer · Tech Lead

    RaDevs — Laravel platforms and the studio’s AI engineering practice.

    • Authored and open-sourced Groundwork, and set the team’s engineering standards and Definition of Done around it.
    • Built a reusable multi-market headless commerce platform: storefront JSON API, back-office admin, retail and wholesale pricing engine, driver-abstracted payments and delivery.
    • Shipped applied AI to production — an intent gateway that validates model output instead of executing it, voice intake behind schema-constrained extraction, OCR and computer-vision pipelines.
    • Engineered the payment and financial subsystems: card tokenization, idempotency-keyed clearing, decimal money with bcmath, accounting and tax export, signed-webhook reconciliation.
    • Architected order-lifecycle and production-workflow systems with multi-station scan tracking, quality control, weighted auto-assignment and centralised state-transition guards.
    • Mentored engineers through review agents and architecture decisions.
  2. Aug 2022Apr 2024

    Full-Stack PHP Engineer

    TerraForce Software — E-commerce, admin and CRM platforms, mobile app APIs.

    • Built and maintained e-commerce backends with subscription payments, local checkout and delivery, multi-language storefronts and response-query caching.
    • Developed admin panels with custom tools, cards, fields and dashboards, including a leads-management CRM with rich-text editing and invoice generation.
    • Built API-first mobile app backends: JWT auth, push notifications, QR codes, two-factor auth, and PDF/Word/Excel document generation.
    • Delivered search-driven features — full-text search, geo-targeting, SMS and messenger notifications, real-time sockets, social login.
    • Integrated an early LLM alongside Google APIs and web-scraping pipelines for content generation.
  3. Jun 2020Aug 2022

    PHP Engineer

    Imrev — E-commerce and corporate platforms, integrations.

    • Built e-commerce and corporate platforms end to end — custom modules, admin panels and storefronts — across concurrent client projects.
    • Integrated payment, shipping and analytics providers, replacing manual client workflows with automated order flows.
    • Optimised page, catalogue and search performance through query tuning, indexing and caching, and owned post-production incident handling.
  4. Jan 2020Jun 2020

    Junior Engineer (C++ / .NET)

    YUKS++ — Legacy desktop maintenance and a WinForms migration.

    • Maintained and extended legacy modules, contributed to a migration to WinForms, and resolved pre-release defects during QA and hardening cycles.

Markets

Israel and Ukraine

Two markets with very different assumptions, which is most of why the work got interesting.

The Israeli work meant Hebrew and right-to-left products, Israeli fintech and accounting systems, and telephony that has to speak to people rather than at them. Right-to-left is where most implementations quietly break: text has to be passed in logical order, because reordering happens per display line after wrapping — a paragraph reversed in advance reads bottom-up the moment it wraps.

The Ukrainian work was commerce and integration at volume: catalogue sync with an ERP, local payment and delivery providers, and platforms cloned per market without forking the codebase.

Languages

How I communicate

English
B2
Ukrainian
Native
Russian
Fluent

Working language on a team is English. Documentation, specs, commit messages and API contracts are written in English regardless of who is reading them, because the next person to open the repository may not share a first language with anyone currently on it.

Leading

How I run a team

Mostly by making the standard checkable, so it survives the week I am not looking.

I set the engineering standards and the Definition of Done, and then I put them in tooling rather than in a wiki page. Groundwork exists because a review checklist that lives in somebody’s head is a checklist that gets skipped under deadline — and because an AI agent will report success with exactly the same confidence whether or not it succeeded.

The part that took longest to learn is that the process has to scale down. A typo and a change to how VAT is calculated do not deserve the same ceremony, and applying the heavy version to everything is how a process stops being used at all.

Next

What I want next

A Senior Backend or Tech Lead role on a product with real domain weight.

Payments, order lifecycles, production workflows, applied AI that has to survive contact with production — those are the problems I am good at and the ones I want more of. Remote worldwide, or relocation. available at two weeks’ notice.

[email protected]Read the CV