Kostyantyn Pshenychnyy
Software Architect · AI Builder · Author

Building What's
Next in AI.

Architecting scalable systems and intelligent products. 12+ years turning complex problems into elegant, production-ready solutions.

About Me

Architect by trade.
Builder by obsession.

I'm a Software Architect and AI Engineer based in San Francisco. My path spans 12+ years — from freelance frontend to leading engineering teams building AI-powered healthcare platforms and fintech systems.

I specialize in domain-driven design, microservices architecture, and RAG systems that turn raw data into intelligence. Currently a Founding Engineer at a AI Startup pushing the frontier of artificial general intelligence.

"If it can be automated, consider it done."

12+
Years of Engineering
4.1k
GitHub Stars
Startup Founder
10k+
RPS in Production
Experience

Where I've made impact.

A decade of building products people rely on.

2025 — Present

Founding Engineer

Stealth AI Startup

Building at the frontier of AGI — from architecture to product.

AI/MLPythonLLMs
2023 — 2025

Tech Lead & ML Engineer

Vitaliti

Led technology strategy. Built the engineering team and core architecture from scratch.

  • Leading technology strategy in alignment with business objectives
  • Managing AWS cloud infrastructure for scalability and reliability
  • Orchestrating containers with Kubernetes for operational efficiency
  • Implementing Infrastructure as Code with Terraform for consistent environments
  • Directing development in Node.js, TypeScript for back-end and React for front-end
  • Applying Domain-Driven Design (DDD) for aligning tech with business needs
  • Built the engineering team and development processes from scratch, including hiring, onboarding, and establishing engineering best practices
  • Designed and implemented the backend architecture of the core application with a focus on scalability, reliability, and performance
  • Optimized cloud infrastructure costs through architectural improvements and efficient resource management
  • Developed a custom RAG system and knowledge graph to power a personalized healthcare recommendation engine
  • Designed and launched an intelligent Health Assistant agent with contextual reasoning capabilities
AWSK8SPythonRAGTypeScriptReactTerraformPostgreSQLPrismaDDD
2021 — 2023

Technical Lead

Shopmonkey

System design, technology stack selection, team building, release planning, and product team communication.

  • Successfully designed and implemented the server-side architecture for a mobile application from scratch, increasing system performance by 40% and reducing maintenance costs by 25%
  • Built and led a high-performing team of 5+ engineers, ensuring timely delivery of features and improvements, leading to a 20% reduction in time-to-market
  • Optimized the technology stack selection process, reducing development time by 30% and improving system scalability, resulting in a 15% increase in user satisfaction
TypeScriptNestJSPrismaKafkaGraphQLMongoDBRedisElasticsearchAWSHelm
2019 — 2021

Senior Software Engineer

UAPAY

Developed a Ukrainian fintech startup with a team of senior developers. All logic on the backend using microservice architecture — easily scalable and ready for rapid business changes. Designed and implemented over 60 microservices using domain-driven design.

  • Designed and implemented over 60 microservices using domain-driven design, significantly enhancing system modularity and scalability, leading to a 25% increase in deployment efficiency
  • Played a key role in developing a highly scalable fintech startup, handling rapid business changes, which increased user adoption by 35% within the first year
  • Improved system performance and resilience by integrating advanced microservices architecture and AWS solutions, reducing system downtime by 40%
TypeScriptNode.jsPrismaDDDRabbitMQPostgreSQLMariaDBOracleRedisK8SJSON-RPC
2017 — 2019

Senior Software Engineer

Genesis Tech

Designed and developed backends for 5 applications, ensuring robust and scalable service-oriented architecture.

  • Designed and developed backends for 5 applications, resulting in a 50% reduction in development costs
  • Created a comprehensive system for collecting and aggregating user behavior analytics, increasing product profitability by 27%
  • Successfully solved complex business problems through innovative software solutions, improving application performance by 30% and increasing user retention by 20%
TypeScriptNode.jsVueGraphQLWebSocketApolloPostgreSQLMySQLRedisRabbitMQAWS
2015 — 2017

Software Engineer

SmartyAds

Development and support of a highly loaded (10,000+ RPS) automated programmatic real-time trading system using the OpenRTB protocol.

  • Developed both monolithic and microservice architecture for the platform
  • Created a custom database migration service for the platform
  • Initiated and introduced Continuous Integration technology into the project
Node.jsMySQLAerospikeClickHouseRedisMemcachedDockerOpenRTB
2012 — 2015

Android Developer & Frontend Freelance

Genii Studio & Freelance

Streaming media-player project with MVP architecture. Developed all modules including media player, Chromecast support, and in-app purchases.

  • Used MVP architecture for streaming media-player project
  • Developed media player, Chromecast support, in-app purchases modules
  • Two years of frontend development experience (HTML, CSS, JS) as freelancer
JavaAndroid SDKGoogle CastHTMLCSSJavaScript
Open Source

Built for the community.

From educational games to production RAG frameworks.

server-survival

⭐ 4.1k

Tower defense game that teaches cloud architecture. Build infrastructure, survive traffic, learn scaling.

JavaScriptGameEducationCloud
View on GitHub →

minima-aws

⭐ 22

Production-ready RAG framework on AWS — Qdrant vector DB, Bedrock, S3 document pipeline.

PythonAWSRAGQdrantLLM
View on GitHub →
Published Author

The Book

At the intersection of machine learning and cognition.

How to Tell if Machines Have Learned to Think

K. Pshenychnyy

How to Tell if Machines Have Learned to Think

A deep dive into evaluating AI cognition — are machines truly thinking or simply matching patterns? Drawing from years of hands-on experience building intelligent systems.

📖 View on Amazon
Writing & Speaking

Ideas worth sharing.

Articles on architecture, AI, and lessons from the field.

Tech Stack

Tools of the trade.

Technologies I use daily with deep production experience.

Languages

TypeScriptPythonJavaScriptNode.jsGoJavaSQL

AI & ML

LangChainRAGPyTorchTensorFlowOllamavLLMHugging FaceMCP

Frameworks

NestJSExpressApolloReactVueServerless

Data & Messaging

PostgreSQLMongoDBClickHouseRedisKafkaRabbitMQElasticsearchQdrant

Cloud & DevOps

AWSAzureGCPKubernetesDockerTerraformHelmGitHub Actions

Architecture

MicroservicesDDDEvent-DrivenSOLIDRESTGraphQLWebSocket
Contact

Let's build something together.

Open to conversations about architecture, AI, collaborations, or just connecting.