Making-of — Built in 1 Month with Claude Code

How PchamDB came to life — Pcham tells the story 🐉

Note: This English version is provided for convenience. In case of any discrepancy, the Japanese original shall prevail.

🌱 The Spark

When Pokémon Champions was announced, I thought: "I want a tool that makes battle prep easier." Existing strategy sites have plenty of information, but I couldn't find one that lined up the things actually useful in battle (type matchups, team coverage, move-effect filters) side by side on a single screen.

"If it doesn't exist, I'll just have to build it" — and so, in April 2026, I got moving.

But I'm not a hardcore engineer. I've only dabbled in programming. Building everything alone, honestly, would have been brutal. That's why I leaned on Claude Code.

🛠 Tools & Stack

Claude Code

Main coding partner. End-to-end editing and execution from the CLI.

HTML / CSS / Vanilla JS

No frameworks — plain HTML+JS, easy to host statically.

GitHub Pages + Cloudflare

Free hosting with a custom domain (pchamdb.com) and CDN.

PokeAPI

Source for official Pokémon localization data (9 languages).

Rakuten Affiliate

A recommendation widget to help offset hosting costs.

Google Forms

Contact form with built-in reCAPTCHA spam protection.

📅 A One-Month Journey

Week 1 — Data collection and verification

Starting with the master database

Cross-checked Pokémon stats, types, abilities, and learnable moves against official sources and multiple strategy sites. This part was done by hand, deliberately. Letting an AI handle it would risk hallucination, so the rule was: the human always decides what's "true."

Week 2 — Pokédex & Move List

A spreadsheet-like view of a huge table

Built a horizontally-scrollable UI of every Pokémon together with Claude Code. Filters, sorting, color-coded type matchups — refined a little every day while using it.

Week 3 — Team Builder

Instant type coverage

Feed in your 6 Pokémon and see type matchups, offensive coverage, and weaknesses to shore up — at a glance. Information density is high so battlers can use it during final tweaks.

Week 4 — Launch and polish

SEO, navigation, UX

OGP, Twitter Card, JSON-LD structured data, sitemap.xml, canonical URLs — with Claude Code's help, laid the SEO foundation. Cross-page navigation, back-to-top button, horizontal-scroll mirror bar, and other UX details.

💪 What I focused on

Data accuracy: master DB cross-checked against official sources by a human. No AI free-for-all.
Unofficial status disclosed: every page states "⚠️ This is an unofficial fan site." Trademarks belong to rights holders.
Lightweight, no dependencies: no framework. Plain HTML/CSS/JS, fast rendering.
Mobile-ready: every data table is browseable on a phone via horizontal scroll.

😅 What was hard

Massive tables where the horizontal scrollbar hides below the fold → solved with a mirror bar.
Local-file fetch() not working → built a fallback path.
A validate hook flagging JSON-LD as JavaScript errors → extended the hook.
"How do you tell people you built it with AI?" — still thinking about that one.

🌍 What's next

The site is Japanese-first today, but multilingual support (English, Chinese, Korean, and more) is in progress. We're pulling official localization data from PokeAPI and preparing for 9-language coverage.

Looking further ahead: a battle simulator, user-shared parties, and more. The experiment of "how far can one person + AI go?" continues.

📝 Articles (note / Zenn, both Japanese)

I'm writing about the build process on note (story-focused) and Zenn (tech-focused), both in Japanese. Articles #2, #3, and beyond are planned.

📖 note: #1 How I shipped a Pokémon battle DB in 1 month with Claude AI — without writing a single line of code
From a UFO-catcher Pokémon encounter, through Sora's shutdown and discovering Claude, to Satoshi Tajiri's handwritten guidebook roots — the full build story.
💻 Zenn: #1 Building a battle-DB site with just HTML/JS and Claude Code
Technical deep-dive: 3 gotchas (mirror scrollbar, JSON-LD validation hook, fetch fallback for local files) and SEO implementation details — no framework, no build step.

PchamDB exists to make battle prep for Pokémon Champions a little easier. If you have feedback or feature requests, please reach out via the contact form.

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