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engineering notes

CV Case Studies

Notes on projects, decisions, and lessons from work and study. They cover backend systems, web products, AI experiments, education projects, and the problem-solving habits I picked up from competitive programming.

~/case-studies/nexius-ai-financial-document-processing

Nexius AI: Lessons from a Financial Document Processing System
September 2025 - May 20266 min read

Nexius AI: Lessons from a Financial Document Processing System

What I learned while working across OCR, parsing, validation, background processing, reporting, and delivery in Nexius AI.

Document ProcessingFastAPIRabbitMQObservability
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~/case-studies/hashigake-b2b-corporate-matching

Hashigake: Multi-Tenant B2B Corporate Matching
July 2024 - March 20255 min read

Hashigake: Multi-Tenant B2B Corporate Matching

How backend integrations, Azure Service Bus, WebSocket services, and React/TypeScript supported a Japanese B2B matching platform.

B2B Platform.NETReactAzure Service Bus
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~/case-studies/pmi-regional-campaign-redemption-engines

PMI Regional Platforms: Campaign and Redemption Engines
June 2025 - August 20254 min read

PMI Regional Platforms: Campaign and Redemption Engines

Full-stack work across Kazakhstan, Chesterfield Philippines, and PRJWHEART using Vue.js, ASP.NET, Sitefinity CMS, and reusable backend patterns.

Full StackVue.jsASP.NETSitefinity CMS
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~/case-studies/education-platforms-competitive-programming-foundation

Education Platforms and Competitive Programming Foundation
2020 - 20255 min read

Education Platforms and Competitive Programming Foundation

The education and algorithmic foundation behind TELISIK, ITB Informatics Engineering, and programming competition achievements.

EducationITBProgramming Competitions
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~/case-studies/dynamic-programming-field-notes

Dynamic Programming: Turning Brute Force Into Something That Scales
2020 - Present6 min read

Dynamic Programming: Turning Brute Force Into Something That Scales

How I think about dynamic programming — from spotting overlapping subproblems in a contest to using the same instinct to design caching and reprocessing logic in production systems.

Data StructuresAlgorithmsCompetitive Programming
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~/case-studies/segment-trees-range-queries

Segment Trees: Answering Range Queries Without Rescanning the Array
2020 - Present5 min read

Segment Trees: Answering Range Queries Without Rescanning the Array

A practical walkthrough of segment trees — the structure that turns O(n) range queries and updates into O(log n) — and why the same idea underlies real-time analytics and time-series systems.

Data StructuresAlgorithmsCompetitive Programming
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~/case-studies/graph-algorithms-field-guide

Graphs: The Data Structure Behind Almost Every Interesting System
2020 - Present7 min read

Graphs: The Data Structure Behind Almost Every Interesting System

Adjacency lists, traversal, shortest paths, and union-find — the graph toolkit I reach for in contests, and the same toolkit that shows up in dependency graphs, service topologies, and marketplace matching.

Data StructuresAlgorithmsCompetitive Programming
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