もじへん！
A browser-based tool for cleaning up Japanese text, separators, and normalization based on rules you define.
Grow What You Make.
A quiet lab where personal development, creativity, and thinking quietly unfold.
Products
A compact selection of the tools and plugins currently published on happas.View all products
Vanilla Form
Shape a Google Form to look and feel like it belongs on your site without the infrastructure headaches.
SproutSVG
A small browser app for turning images into SVG locally, with live preview and direct export in the same flow.
Slug-Free Permalinks
A WordPress plugin that switches URLs to stable ID-based permalinks, reducing maintenance and broken links.
Marklane
A WordPress plugin for fast Markdown publishing, with image resolution and multilingual post linking.
Blog
Notes on making things, trial and error, and what I am thinking about. The blog itself is managed in WordPress.View all posts
What if You Run Out of Codex or Claude Code Paid Limits? Trying Out Free Coding Agents
We explored ways to keep coding for free when paid limits for Codex or Claude Code are reached. Comparing OpenCode, Hermes Agent, Cline, and Kilo Code, we share why we ended up using Kilo Code as a free backup agent.
From Financial Apathy to My Current Investment Style
How a once financially careless beginner learned from failures, found the right balance with core and satellite assets, and established a personal investment style.
GPT-5.6 Unleashed! Key Features, Pricing, and Use Cases for Sol, Terra, and Luna
GPT-5.6 is finally unleashed! Explore the features, pricing, and practical use cases for Sol, Terra, and Luna to optimize your AI routing.
Feature Flags in config.toml and Rules in AGENTS.md: Structuring Codex Configurations
An overview of the [features] configuration block in OpenAI Codex's config.toml. Explains key settings like memories and hooks, along with practical configuration examples.
Astro 7.0 Major Release! Reviewing Key Changes and Future Use Cases
Astro 7.0 has been released in June 2026. Review key changes including Vite 8, Rolldown integration, Rust-based compiler and markdown parser Sätteri, AI agent detection, and advanced routing caching.
How to Handle Foreign Currency Transactions After Cancelling Platinum Preferred? Recommended Card Comparison to Beat Overseas Fee Increases
What should you use for foreign currency payments after cancelling the Sumitomo Mitsui Card Platinum Preferred, which only cost 0.63% in real fees? I compared the latest fees and reward rates of 8 cards on hand to find the best alternative.