Богдан

Bohdan Shtelmakh
Full-Stack Software Engineer | Node.js · TypeScript · React
Khmelnytskyi, Ukraine | Open to remote work
[відкрити контакти](див. вище в блоці «контактна інформація») | [відкрити контакти](див. вище в блоці «контактна інформація»)
github.com/BohdanShtelmakh | [відкрити контакти](див. вище в блоці «контактна інформація»)

SUMMARY
Full-Stack Software Engineer with 4 years of commercial experience in Node.js, TypeScript, React and PostgreSQL.
Strongest in backend architecture, APIs, data processing and integrations, with hands-on frontend delivery.
Experienced in owning backend development from technical design through deployment and production
maintenance across SaaS, AdTech, payments, and AI applications.

EXPERIENCE

Software Engineer | RexSoft | November 2023 - July 2026
Frequently served as the primary backend engineer across client products, owning architecture, data models,
integrations and delivery. Contributed React features and administrative interfaces alongside backend development.
Independently provisioned and configured cloud-hosted server infrastructure and implemented CI/CD and
deployment workflows across multiple production applications.

AdTech Platform | Data Synchronization and Reporting
Designed API architecture, database models and a dedicated data synchronization service integrated with The
Trade Desk.
Implemented cursor-based ingestion, checksum-based change detection, PostgreSQL upserts and batch
persistence; orchestrated report processing with BullMQ workers and retry/backoff handling.
Automated GitLab-triggered deployments to skip runs without new commits and reinstall dependencies only
when package manifests changed; contributed supporting frontend features.

B2B Services Marketplace | Billing, Payments and AI
Owned backend architecture and business workflows, implementing configurable Stripe subscriptions, per-user
usage tracking, subscription management and marketplace payments through Stripe Connect.
Integrated Google Gemini for AI-assisted project creation from images, structured data extraction and
classification across 100+ service categories; added model selection, caching and retries.
Delivered React frontend features and administrative functionality connected to marketplace APIs.

AI Voice Calling Platform | Multi-Tenant SaaS
Designed and developed a Python/Flask backend with PostgreSQL, tenant-scoped APIs, role-based operations,
campaign dispatch and LiveKit telephony integrations.
Integrated a pgvector-backed knowledge base for RAG, transcription, AI-assisted call processing and automated
follow-up workflows.
Added dispatch guards, retry controls and stuck-call recovery; corrected usage billing to stop at caller hang-up
rather than delayed session teardown.

Real Estate CRM | Multi-Portal Business Platform
Led backend development for role-specific workflows, business automation and integrations; evolved database
relationships and schemas as agent and agency portals expanded.
Implemented document-access workflows with AWS S3, backend-mediated streaming, code verification and time-
limited links; maintained deployment automation and file-migration tooling.

Logistics SaaS | Operations and Real-Time Messaging
Developed transportation, warehouse, document and permissions workflows in a logistics backend.
Designed a separate Node.js/Socket.IO messaging service for direct, group and business-context conversations,
with attachments and preview generation for document and media formats.

Localization Service | AI Translation and Maintenance
Developed a TypeScript localization service integrating Google and OpenAI providers, tenant-aware retrieval,
caching, batched persistence and Kafka usage events.
Maintained existing SaaS services through dependency security updates, vulnerability remediation and database
TLS configuration improvements.
Additional work: geospatial functionality and timezone-aware scheduling; Apple/Google subscription-verification
fixes; WhatsApp, Telegram and email lead aggregation with Notion.

Software Engineer | devSmile | August 2022 - October 2023
Developed Java/Spring backend services and REST API integrations; contributed to Node.js microservices and
React frontend features.
Integrated Kafka for asynchronous processing and contributed Docker deployment workflows; gained earlier
experience with Kubernetes and Google Cloud Platform.

OPEN SOURCE
html-pdf-lite | Chromium-Free HTML-to-PDF for Node.js
Created and published a library with automated CI, performance benchmarks and external contributions; 6,000+
cumulative npm downloads.
github.com/BohdanShtelmakh/html-to-pdf | npm: html-pdf-lite

TECHNICAL SKILLS
Languages and frontend: TypeScript, JavaScript, Python, Java; React, Next.js, HTML/CSS, Tailwind CSS
Backend: Node.js, AdonisJS, NestJS, Express, Flask, Spring, REST APIs, WebSockets, Socket.IO, BullMQ, Kafka
Data: PostgreSQL, Redis, MongoDB, MySQL, pgvector; Prisma, Drizzle ORM, TypeORM, Lucid ORM
Cloud and delivery: AWS (EC2, S3, RDS), Docker, Linux, Nginx, PM2, GitHub Actions, GitLab CI
AI and integrations: OpenAI, Google Gemini, RAG, LiveKit, Stripe/Stripe Connect, Google APIs, Firebase, Twilio
Testing and documentation: Jest, Japa, OpenAPI/Swagger

EDUCATION AND LANGUAGES
Khmelnytskyi National University | Automation, Computer-Integrated Technologies and Robotics | 2024 - Present,
part-time
Khmelnytskyi Polytechnic College | Software Engineering | 2020 - 2024
Ukrainian: Native | English: C1