Дмитро

Dmitro Buzhilov Email: [відкрити контакти](див. вище в блоці «контактна інформація»)
Location: Ukraine • Remote
Go Backend Developer Telegram: @dmytro_wor

PROFESSIONAL SUMMARY
Go Backend Developer with 2+ years of experience building reliable microservices, RESTful APIs, and real-time
backend systems. Solid foundation in Go concurrency (goroutines, channels, sync primitives), relational database
design, and query optimization (PostgreSQL indexing, transaction management, connection pooling). Experienced
in designing inter-service communication using gRPC and message brokers (RabbitMQ, NATS), applying Clean
Architecture, and writing memory-efficient networking code.

TECHNICAL SKILLS
Languages & Core: Go (Goroutines, channels, sync/atomic, pprof, memory profiling, GC basics), SQL,
Rust (FFI basics), CGO, Bash
Databases & Storage: PostgreSQL (B-Tree indexes, transaction isolation, pgxpool, migrations), Redis
(Caching, TTL, singleflight), MongoDB, BadgerDB
Messaging & Brokers: RabbitMQ (Topic Exchanges, Work Queues, Dead Letter Exchanges), NATS
JetStream
Architecture & Protocols: Clean Architecture, Microservices, gRPC, Protocol Buffers, WebSockets, RESTful
APIs (Gin, Chi, Echo)
Networking & Security: TCP/UDP socket programming, quic-go, STUN (NAT traversal), JWT
(Access/Refresh tokens), Signal Double Ratchet, memguard
Tools & Infrastructure: Docker, Docker Compose, Git, Linux (Debian/Ubuntu), GitLab CI/CD, GitHub Actions,
Make, Postman

PROFESSIONAL EXPERIENCE
E-Commerce Platform (Digital Goods & Gaming | Go Backend Feb 2024 – Present | Remote
Marketplace) Developer
Microservices-based marketplace for digital game keys, software licenses, and automated instant order delivery.
• Developed core Order and Inventory microservices in Go communicating via gRPC and Protobuf, sustaining 250+
peak RPS with sub-60ms average API response times.
• Implemented the Transactional Outbox pattern with PostgreSQL and RabbitMQ, guaranteeing atomic event
publishing and eliminating state discrepancies between services.
• Architected stock reservation logic using PostgreSQL pessimistic locking (SELECT ... FOR UPDATE) and database
transactions, completely preventing overselling and race conditions during promotional campaigns.
• Integrated external payment gateways (PayPal, Stripe webhooks) with idempotency keys stored in PostgreSQL,
preventing duplicate charges upon network retries.
• Optimized slow database queries by adding composite B-Tree indexes and refining execution plans with EXPLAIN
ANALYZE, cutting query latency on 800k+ row order tables by ~60%.
• Built a real-time buyer-seller customer support chat using WebSockets and MongoDB for storing message history
and user ratings.

PROFESSIONAL EXPERIENCE (CONTINUED)
Decentralized Mesh & Security R&D | Go Systems Sep 2024 – Present | Proprietary / Remote
(EchoFog Systems) Engineer
High-performance encrypted peer-to-peer communication daemon and decentralized networking core.
• Architected end-to-end cryptographic pipeline integrating BIP-39 mnemonic key derivation via Rust FFI with Go-
based X3DH and Signal Double Ratchet state machines in memguard enclaves for secure messaging.
• Engineered low-latency networking layer combining UDP demultiplexing, STUN (NAT traversal), and quic-go
runtime over a single shared port with protocol mimicry to bypass DPI packet inspection.
• Designed lock-free circular ring buffer (SPSC) utilizing sync/atomic primitives, slashing heap memory allocations
by ~42% under high packet processing throughput.
• Implemented decentralized peer discovery leveraging Kademlia DHT and epidemic Gossip protocols, cutting
network node convergence time by 45%.

Modular SaaS CRM System (HoReCa | Go Backend May 2023 – Jan 2024 | Remote
Automation) Developer
Hospitality management platform automating restaurant table reservations, waitstaff POS orders, and inventory.
• Built real-time WebSocket order notification gateways in Go, maintaining 800+ concurrent active connections
across 30+ client venues for instant kitchen display updates.
• Structured backend services using Clean Architecture (domain entities, usecases, repositories), decoupling
business logic and achieving 78% unit test coverage.
• Designed relational multi-tenant database schemas in PostgreSQL (organizations, tables, menus, recipe
ingredients) with unit conversion logic for automatic inventory deduction.
• Configured connection pooling with pgxpool and structured logging via zerolog, reducing database connection
wait times and enhancing production observability.
• Implemented asynchronous event dispatching with NATS JetStream to handle background inventory deductions
without blocking interactive POS checkout requests.
• Mitigated Cache Stampede on high-traffic restaurant menu endpoints using Redis caching combined with Go's
singleflight group mutexes.

EDUCATION
Odessa National Polytechnic University (ONPU)
Bachelor of Science in Computer-Integrated Technologies