MerMark Editor, a Markdown editor that can draw Mermaid diagrams, gains Japanese localization from v0.8.1 thanks to volunteer contributions

Japanese added to MerMark Editor

MerMark Editor is a free app for writing text in Markdown, a simple way to format text. It can also draw Mermaid diagrams. Setup only offers English and Polish, but users can switch the interface to Japanese in the settings. Version 0.8.1 was released on October 12, and a volunteer wrote up how the Japanese support was made.

Key facts

• Version 0.8.1 was released on October 12, 2026.
• Japanese is chosen in Settings, under the Appearance tab, in the Language option.
• The app works on Windows (64-bit, Windows 10 or later), macOS, and Linux.
• The license is MIT, and the app is free to download from the release page.

What the app does

MerMark Editor is a desktop app built with Tauri, a tool for making apps that run on many systems. It lets users see their code and a preview side by side. It also has WYSIWYG editing, where the text looks finished while you type. It supports Marp for making slides, and it can work with AI tools such as Claude Code, Codex, and Ollama. Ollama lets users run AI on their own computer, so it can work offline. The app stores documents on the user's computer, not in the cloud.

Why it matters

Japanese speakers can now use the app in their own language without changing the setup. It also shows how volunteers can help open-source projects reach more people. Because the app has no code signing, users may see warnings when they download it or open it for the first time.

What to watch

• Whether more languages are added by volunteers.
• Whether code signing is added, which would reduce download and startup warnings.
• New releases that build on the Japanese support.