We build web, app, and AI systems that become real products

From MVPs to live services, Ptokos connects Next.js, React Native, NestJS, LLM workflows, and cloud operations.

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1,000+ registered app users

10,000+ public download signal

13s → 0.4s query improvement

Product Engineering

Built for launch and operations

Mobile apps, public services, and learning products designed with operating workflows.

Shipped product surfaces

Stack: Next.js, React Native, NestJS, LLM, GCP
Focus: Web apps, mobile apps, AI automation, data pipelines
Proof: Live products, public-sector systems, app store releases

What Ptokos Does Well

Product-minded Engineering

We design user flows and operating constraints instead of simply translating feature lists into screens.

Full-stack Delivery

Frontend, backend, database, and deployment automation are handled as one product system.

Operational Quality

Performance, security, testing, monitoring, and deployment are treated as production requirements.

What We Build

Services

Focused development services for projects that need to move from MVP validation to reliable operation.

Next.js Website and Admin Development

Build search-friendly web products, admin consoles, and dashboards with Next.js App Router.

Expected outcome

Pages become discoverable and indexable

Next.jsReactTypeScriptTailwind CSSVercel

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React Native App Development

Build iOS and Android products with Expo, React Native, and a production-minded mobile architecture.

Expected outcome

Launch both stores from one codebase

React NativeExpoTypeScriptiOSAndroid

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AI and LLM Automation Development

Connect document summarization, OCR, structured generation, and search assistance into real product workflows.

Expected outcome

Automate repetitive document processing

LLMOpenAI APIClaude VisionOCRNestJS

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Web Crawling and Data Collection Systems

Build data collection pipelines for dynamic pages, large files, and long-running jobs.

Expected outcome

Handle heterogeneous site structures

PythonSeleniumPuppeteerMySQLData Pipeline

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Cloud and DevOps Setup

Prepare deployment, logs, tests, and infrastructure automation so MVPs can become live services.

Expected outcome

Reduce manual deployment risk

GCPCloud RunDockerTerraformKubernetes

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Project Case Studies

Selected products and client projects are documented around problems, implementation choices, and outcomes.

Live

BudongsanBank Agency Manager

A cross-platform business app for real estate agency members, released on both iOS and Android and operated for 1,000+ registered users.

Proof

Released the app on both App Store and Google Play

Cross-platform MobileiOSAndroidApp StoreGoogle PlayB2B Operations

Status: Live

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Live

PourLog

A six-language coffee tasting SaaS across iOS, Android, Web, Admin, and API, with OCR-assisted record creation and a TypeScript monorepo.

Proof

Built iOS, Android, Web, Admin, and API surfaces from one product architecture

ExpoReact NativeTypeScriptNestJSNext.jsPostgreSQL+4

Status: Live

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Redictionary (WordBrain)

An AI-powered English-Korean vocabulary learning service combining structured dictionary generation, Redis caching, TTS audio, and quizzes.

Proof

Built a full-stack vocabulary service with React, NestJS, Redis, OpenAI, and Google Cloud

NxTypeScriptReactViteNestJSRedisJSON+4

Status: In Development / deployment history

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Live

JodalN

A production-grade public procurement SaaS that collects Korean G2B bid data, summarizes attached documents with LLMs, and supports high-speed search.

Proof

Built a production-grade SaaS with 19 Prisma models and extensive database indexing

Next.js 15NestJS 11TypeScriptPrismaPostgreSQLLLM+4

Status: Live

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MVNO Hub Renewal

A public-service renewal project that delivered telecom order integration APIs, order-status Kakao AlimTalk notifications, and a 32x Oracle query improvement.

Proof

Delivered real-time order integration APIs for external telecom operators

JavaSpringOracleRESTful APIKakao AlimTalkGit

Status: Delivered

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Delivered

IBS Education Management System

A public-sector SI project that integrated training operations, attendance, online lectures, certificates, payments, and role-based administration.

Proof

Launched an integrated training platform for IBS employees

JavaSpring FrameworkeGovFrameworkJSPjQueryMyBatis+3

Status: Delivered

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Expertise

GiJu Kang

Product Engineer

CNCK Organizer - Community Ops Sub-leader

I build products with TypeScript, React, Next.js, NestJS, Spring Boot, Python, and cloud platforms. My work spans web crawling, mobile apps, LLM automation, public-data SaaS, and operations tooling.

Trust Signals

Backend code reviewer and mentor at Naver Connect Foundation
CNCF Kubestronaut, CKA, CKAD, CKS, KCNA, KCSA
AWS Solutions Architect Associate, AWS Developer Associate, Google Cloud Associate Engineer
Delivered live apps, public-sector SI, data collection, and LLM productization projects

Ready to turn the project into a product?

For web, app, AI automation, or cloud operations work, start with the concrete problem and timeline.

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