# jammaru

> Public portfolio of jammaru (@jammaru_lab), a 19-year-old technical college student in the class of 2027 and a software engineer. The work is software for LLMs, agents, and MCP.

Use only the pages listed here. Do not infer an employer, school name, location, or any achievement these pages do not state. Japanese pages are canonical. English pages translate the same public facts.

## Site

- [Home](https://jammaru.com/): Portfolio home
- [Home, English](https://jammaru.com/en/): English home
- [Works](https://jammaru.com/works/): Project index
- [Works, English](https://jammaru.com/en/works/): English project index
- [Writing](https://jammaru.com/blog/): Selected writing on this site
- [Writing, English](https://jammaru.com/en/blog/): English writing index
- [Uses](https://jammaru.com/uses/): Tools in current use: TypeScript, Astro, and GitHub
- [Uses, English](https://jammaru.com/en/uses/): English uses page

## Works

- [jev-affected](https://github.com/jammaru/jev-affected): CLI that reads a Git diff against conditions written in natural language and turns that into a safe plan for tests, builds, and CI that already exist. `plan` does not run commands. `run` executes only configured commands. Missing credentials, timeouts, and sensitive diffs fail open to RUN.
- [Jev Lab](https://github.com/jammaru/jev-lab): A lab for Jev decision-making. Hundred is a small town of 100 NPCs. Jev Shogi keeps every reply legal. The engine holds the rules; Jev chooses only the next action. Vite, React, and PixiJS monorepo.
- [llm-abi](https://github.com/jammaru/llm-abi): TypeScript library that compiles one JSON Schema for providers such as OpenAI, Anthropic, and Gemini, then reports compatibility and checks the result at runtime. Site: https://llm-abi.pages.dev/ Notes: https://zenn.dev/manmaru_ai/articles/llm-abi-schema-compatibility
- [theapps-mcp](https://github.com/jammaru/theapps-mcp): MCP server and Agent Skills for the theapps.jp Apps API. Agents can work with customers, payments, coupons, Discord, and webhook signature checks. Read-only unless a write is confirmed. Site: https://theapps-mcp.pages.dev/
- [shukatsu-skills](https://github.com/jammaru/shukatsu-skills): Agent skills for job-search practice: dialogue-based self-analysis, mock interviews, and drafting or reviewing answers. Supports Cursor, Claude Code, and Codex.

## Writing

- [Zenn](https://zenn.dev/manmaru_ai): Technical articles
- [An Introduction to Functional Programming with OCaml](https://zenn.dev/manmaru_ai/articles/ocaml-introduction): 2026-09-04
- [Checking JSON Schema Compatibility Across LLMs](https://zenn.dev/manmaru_ai/articles/llm-abi-schema-compatibility): 2026-08-29
- [A Practical freee MCP Setup Guide](https://zenn.dev/manmaru_ai/articles/freee-mcp-setup-guide): 2026-03-10
- [Building a Web Server on Ubuntu](https://zenn.dev/manmaru_ai/articles/79f0d63e079393): 2024-11-26
- [note](https://note.com/jammaru): Essays
- [Is the ¥6 Million Starting Salary Era Really Good News?](https://note.com/jammaru/n/nc5e38e5f8f38): 2025-12-11
- [Technical Interviews for the Class of 2027 Are Harder Than They Look](https://note.com/jammaru/n/ne00f69c38fec): 2026-01-16
- [What Changes for Engineers in the AI Era?](https://note.com/jammaru/n/n3cb9406faa67): 2026-05-03

## Profiles

- [GitHub](https://github.com/jammaru): @jammaru
- [X](https://x.com/jammaru_lab): @jammaru_lab
- [Mond](https://mond.how/ja/jammaru): Public Q&A