Jakub is a fiercely independent and exceptionally talented software engineer, a true generalist with a purist's dedication to quality. Jakub is one of a kind mind with rare blend of deep technical expertise, creativity and business operations which have been building themself since youngest years which eventually contributed to his vision more than anything else making person who's able to take a single spark of idea and turn it into high-quality product delivered into customer's hands.

Skills

Web Development

Intermediate
  • HTML and JavaScript
  • Static Site Generators (SSG)
  • Single Page Applications (SPA)
  • Progressive Web Applications (PWA)
  • Server-Side Rendering (SSR)
  • Client-Side Rendering (CSR)
  • Web Components
  • Web APIs
  • WebSockets
  • WebRTC
  • RESTful APIs
  • GraphQL
  • Webhooks

Software Development

Advanced
  • Web Applications
  • Desktop Applications
  • Mobile Applications
  • Cross-Platform Applications
  • Real-time Applications
  • Design and Architecture
  • Software Testing
  • Quality Assurance
  • Software maintenance

Leadership & Management

Intermediate
  • Release Engineering
  • Requirements Engineering
  • Configuration management
  • Product management
  • Project management
  • Software Engineering Economics
  • Agile
  • Kanban

TypeScript

Master
  • Generic Types
  • Type Inference
  • Type Guard
  • Unions
  • Intersection Types
  • Type Assertions
  • Mapped Types
  • Decorators
  • Advanced Function Types
  • Functional Patterns (fp-ts)
  • Metaprogramming
  • TypeScript Compiler API
  • Transformers

System Design

Intermediate
  • RDBMS
  • SQL
  • NoSQL
  • NewSQL
  • Reverse Proxy
  • Load Balancing
  • Caching
  • Message Queues

System Administration

Beginner
  • SMB
  • LDAP
  • NFS
  • SSH
  • HTTP/HTTPS
  • FTP
  • Service Management
  • Backup Management
  • Containerization
  • Container Orchestration
  • Virtualization
  • FS (btrfs,zfs,mdraid,lvm2)
  • IaC (terraform)
  • CM (ansible)

Work Experience (2)

Feb 2023 - Jul 2024
Mid/Senior/Lead Back-end Developer
stepapp.pl
Led the backend development (80% ownership) of a subscription-based home cleaning service platform, driving the modernization from legacy Django/Python to TypeScript-based architecture.
  • Architected and maintained core backend services within a microservices-oriented environment (150+ entities), using Domain-Driven Design (DDD) principles, Event Storming, and Context Mapping to define and manage bounded contexts, minimize coupling, and enhance maintainability.
  • Implemented two GraphQL APIs (storefront and workforce) following industry standards (RFCs 3339, 9457, 6638) and integrating crucial middleware components for Authentication (AuthN), Authorization (AuthZ), Caching (Keyv/Local/Redis), and efficient data loading (Dataloader with Prisma, TypeORM, and PostgreSQL).
  • Engineered and maintained critical e-commerce functionalities, including a multi-provider Payment Gateway (Stripe, Stripe Billing, manual transactions), a bespoke Content Management System (CMS), a dynamic Checkout/Storefront, and a calendar-based Reservation system.
  • Spearheaded the full software development lifecycle (research, design, implementation, testing, deployment, and maintenance) for key system components.
  • Managed and optimized PostgreSQL databases, leveraging TypeORM and Prisma for data access and management within the GraphQL API layer.
  • Utilized database introspection techniques and developed custom migration scripts to transition from a legacy Django/Python database to a new TypeScript-based schema.
  • Collaborated with DevOps to manage and optimize cloud infrastructure on AWS using Infrastructure-as-Code (IaC) principles and Terraform.
  • Provisioned and maintained key AWS services, including AppRunner, RDS (PostgreSQL), ElastiCache (Redis), and Secrets Manager, ensuring application scalability, reliability, and security.
  • Developed and maintained an automated release pipeline (ARA) using GitHub Actions, incorporating changelog generation (git-cliff), Docker artifact packaging, and CI/CD workflows for consistent and efficient deployments.
  • Enhanced developer experience by creating reproducible development environments using Nix (Flakes and devenv), supporting both devcontainers and bare-metal installations, ensuring parity with staging.
  • Implemented comprehensive application observability using OpenTelemetry and NewRelic, integrated with request tracing context and AsyncLocalStorage in a Node.js environment to enable proactive monitoring, performance analysis, and efficient debugging.
  • Collaborated with front-end teams to define and implement an automated Behavior-Driven Development (BDD) test suite for End-to-End (E2E) testing of GraphQL APIs, ensuring high-quality releases and minimizing production defects.
  • Employed Agile Kanban methodologies, actively participating in code reviews, upstream monitoring, and documentation efforts (system and domain) using Git Flow and trunk-based development practices.
  • Adhered consistently to design principles (SOLID, EIP) and followed relevant industry standards to create quality code.
  • Grey-hatted social engineering operations in order to protect software system from unecessary bloat and rapid changes from business until requirements were clearly estabilished.
Mar 2023 - Aug 2023
Intern/Junior Back-end Developer
nextrope.com
Developed and maintained RESTful APIs for blockchain-based products using TypeScript.
  • Development and testing of RESTful APIs developed with usage of TypeScript (or rather JavaScript in TypeScript) programming language on Loopback 4 and Nest.js frameworks.
  • Implementation of persistance mechanisms based on traditional RDBMS (PostgreSQL) and decentralized object storage (IFPS) to build "decentralized" solutions.
  • Maintainment, development and quality assurance of legacy codebase related to investment portal for initial coin offerings, yet without access to any critical infrastructure.
  • Integration with ERC-20 and ERC (NFT) smart contracts on Ethereum and Polygon networks.
  • Research, Design and Development of blockchain-based products (dApps) with usage of Event-Driven Architecture (EDA) based on Capture Data Change (CDC) technology.
  • Participation in process of maintainable and development of platform to distribute Ethereum ERC-20 Standard Tokens for FIAT currencies (Initial Coin Offering process).

Projects (1)

Neuronek
 https://github.com/keinsell/neuronek
🧬 Rust-based terminal application which was made to track my intake of caffeine and protect me against potentially unwanted sleep schedule interruptions, utilizing my neuroscience and pharmakinetic knowledge I have decided to also calculate most efficient times to write second coffee to maintain a steady and predictable peak.
  • Application of traditional UNIX principles for CLI applications
  • Pre-processed and mined multiple datasets (PsychonautWiki, Erowid, Drugbank) in total ~3 GB raw data
  • Platform-specific packaging for statically compiled binary

Languages

English

Basic

Polish

Basic

Assasembly X86

Native

Interests

Programming Languages

  • Type Theory
  • Category Theory
  • ReScript/ReasonML/OCaml
  • Rust
  • Gleam
  • Nu

Operating Systems

  • Userspace Customization
  • Operating System Architecture
  • Kernel Architecture and Design
  • Package Management
  • OpenSUSE
  • NixOS
  • Arch Linux

Semantic Web (Web 3.0)

  • Linked Data
  • Ontologies
  • Concept Maps
  • RDF
  • SPARQL

Neuroscience

  • Pharmacokinetics
  • Neurotransmitters
  • Neuropharmacology
  • 5HT2A Receptor Agonists

Finances

  • Day Trading
  • High-Frequency Trading

Artificial Intelligence

  • SOTA Large Language Models (LLM)
  • Deep Learning
  • Machine Learning
  • Agentic Systems

Decentralized Systems

  • Fog Computing
  • DAOs
  • Zero-Knowledge Proofs

Cybersecurity

  • Social Engineering
  • OSINT

References

“Please notice it's hard to keep everything in mind when you live like that. I do not count times where I have failed interview because I didn't remember definition of closure or any other non-sense. I have internet, notes and books for that. I am not a walking encyclopedia, I am an engineer who was learning how to resolve problems and deliver value instead of learning definitions but not using them at all.”
Jakub Olan