Single-file project management tool. No server. No installation. Your data stays where you put it.
Built for engineers who can’t use cloud tools at work.
On-site at a client? Strict security policies? No internet access?
Jira, Notion, and Asana all send your data to the cloud. TaskFlowZero doesn’t.
Everything stays on your PC or your company’s network. Always.
One HTML file. That’s it.
Files are stored locally or on your internal shared folder. Zero cloud communication. Works perfectly in air-gapped or restricted environments.
Just open taskflowzero.html in Chrome or Edge. No IT requests. No setup. No admin rights needed.
Select a shared folder and everyone can read and edit the same data. Conflicts from simultaneous edits are resolved automatically — or manually — with 3-way merge.
| View | Description |
|---|---|
| List | GitHub Issues-style, grouped by milestone, drag to reorder, checklist progress column |
| Kanban | Drag cards across status columns |
| Gantt | Drag bars to adjust dates, with progress lightning line |
| Burndown | Visualize sprint progress by story points |
| Wiki | Write specs and docs in Markdown, auto-saved on preview |
Open taskflowzero.html in Chrome or Edge, then click ✨ New to select a folder.
any-folder/
├── taskflowzero.html ← open this (can live outside the data folder)
├── project_P1.json ← auto-created when you add a project
└── files/ ← auto-created when you attach a file
└── P1/
Select a shared folder (OneDrive, NAS, file server, etc.) and everyone points to the same place.
shared-folder/ (OneDrive / NAS / file server)
├── project_P1.json ← one file per project, auto-created
├── project_P2.json
├── project_P3.json ← independent files = fewer conflicts
└── files/ ← attachments (auto-created)
├── P1/
└── P2/
Because each project lives in its own JSON file, two people editing different projects at the same time will never conflict. If they edit the same project simultaneously, 3-way merge handles it automatically or prompts for manual resolution.
Place these files alongside the HTML for complete offline operation:
any-folder/
├── taskflowzero.html
├── marked.min.js ← Markdown rendering
└── chart.min.js ← Burndown chart
Supported browsers: Chrome / Edge (requires File System Access API)
A cross-project dashboard showing all tasks assigned to you, @mentions directed at you, and related activity — all in one place. Unread mention counts and assigned task counts appear as badges in the sidebar.
Type @ in any comment, task description, or Wiki to trigger member autocomplete. Mentioned members are notified in the My Tasks screen.
Every text area — comments, task descriptions, Wiki, and the task creation modal — has a formatting toolbar with Bold (Ctrl+B), Italic (Ctrl+I), Code, List, and Heading buttons.
Click the 📎 button to attach files or images. Attachments are saved to files/P{n}/ inside your data folder. Images render inline; other files appear as download links.
Log estimated and actual hours per comment via the + Add Effort button in the comment area. Hours accumulate as a running history on each task.
The launch screen shows up to 10 recently opened folders. One click to reopen — no folder picker required.
URLs support the format #[FolderName-]P1-42-C3, letting you share a link that jumps directly to a specific comment.
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| Project List | Gantt Chart |
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| Task Detail | Wiki |
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| Burndown Chart | My Tasks |
Extend functionality by editing plugin/plugins.js — no changes to the main HTML required.
| Plugin | Description |
|---|---|
plugin_lang.js |
Switch UI language between Japanese and English |
plugin_csv_export.js |
Export task list to CSV |
plugin_overdue_badge.js |
Show overdue task count in the sidebar |
Click the 🔌 button in the top-right header to manage plugins through a GUI — no need to edit plugin/plugins.js manually.
First time only: Clicking 🔌 will prompt you to select the
plugin/folder. It’s remembered automatically after that.
See PLUGIN_DEVELOPER_GUIDE.txt to build your own plugins.
TaskFlowZero has no login or authentication. This is intentional.
The main purpose of login in cloud services is to identify “whose data is this.” Since TaskFlowZero stores everything on your own PC or internal network, access control is handled by your OS and network permissions — not the app itself.
Managing IDs and passwords inside the app would only add overhead and introduce new security risks. Keeping it simple — just open the folder and start working — is the point.
project_P1.json, project_P2.json …)files/P{n}/, managed via the tfz:// protocolThis project was built together with Claude, an AI assistant by Anthropic.
Design, implementation, debugging, docs — pretty much everything happened through conversation. “I want this feature.” “This feels off.” That back-and-forth is how TaskFlowZero came to be.
Built in collaboration with Claude by Anthropic.
For commercial licensing inquiries, please open an Issue.