Resume — Danya 峠の夢

I build web services and automate business processes — from idea to launch.

Spec-first development with Claude Code. See my workflow below.

Experience

2024 — now

Full-stack developer, freelance

Web services and integrations for businesses.
Since 2026: spec-driven development with Claude Code.
2022 — 2026

Graphic design, freelance

Stickers, print and apparel, social media content.
2020 — 2022

.NET developer

Freelance, personal and study projects;
in-house at Engy in 2022.
C#, WPF, ASP.NET Core, Entity Framework.

Backend: Java, Spring Boot, Spring Modulith, Spring Security
Frontend: TypeScript, SvelteKit (often SSR and BFF), UI/UX design
Data: PostgreSQL, Hibernate/JPA, Liquibase, RabbitMQ, Redis
Infrastructure: Nginx, Docker Compose, Fluentd, Timeweb App Platform or a Debian VPS
AI: Claude Code, Claude Design, Spec-Driven Development
Integrations: YooKassa, Yandex Pay, CDEK, Russian Post, Yandex Delivery, Bitrix24, CloudKassir, Unisender Go

/draft — a rough idea of the feature, grounded in the codebase, with additional suggestions from the AI.
/interview — working through the feature question by question until "we reach a shared understanding", down to the smallest details like i18n keys.
/PRD — the spec document the AI works from, built from the interview and the codebase. Optionally, a /research snapshot for things like external API documentation.
/review — an independent agent checks the PRD for security, reliability and performance issues.
/design (optional) — generates a Claude Design brief from the PRD and the codebase. I iterate on the design there, prepare a handoff package, and go the next stage.
/finalize — resolves any open questions left in the PRD, again as an interview.

/build — fully autonomous implementation that can run for several hours, spawning agents like test-writer, implementer and stage-reviewer.

/accept — verifies the result against the spec's acceptance criteria and surfaces all findings and decisions made during the build.
PR — I fix leftover findings, personally review the most sensitive parts of the code, then deploy.