Obsidian

TAS Score: S2/3 – D3/5 – A2 / T0

Brief Description

Local-first knowledge management app based on plain Markdown files stored on your device. Rich plugin ecosystem. Free for personal use, paid for commercial and sync.

Architectural Role

Applications layer: personal knowledge base, note-taking, writing, and research tool. Files live on your filesystem – Obsidian is a viewer and editor, not a storage service.

Technical Autonomy

  • ✅ Works without internet (fully offline; all files are local Markdown)
  • ✅ Stores data locally (plain .md files in a folder you choose)
  • ❌ Does not require external accounts – no account needed for local use, but Obsidian Sync and Publish require an account
  • ✅ Allows data export (files are plain Markdown – nothing to export, they’re already yours)
  • ❌ Provides offline updates – updates are pushed by Obsidian; app itself is proprietary

Philosophical Assessment (whose.world criteria)

Criterion Status Comments
Pause Yes Close the app; files remain. No background sync unless you enabled Obsidian Sync.
Exit Yes Files are plain Markdown in a regular folder. Stop using Obsidian and keep everything. Open them in any text editor.
Recoverability Partial Local file versioning via plugins. No built-in backup. Depends on your filesystem and external backup tools.
Visibility No Proprietary application. Source code not available. Plugins are open source, but the core is closed.
External Dependencies Partial Core app works fully offline. Obsidian Sync and Publish are cloud services tied to Obsidian accounts.

Why A2 and not A3

Obsidian scores well on Pause and Exit – your data is plain Markdown, fully portable, no lock-in. But the application itself is proprietary (T0), updates are controlled by the company, and there’s no way to audit what the app does. If Obsidian disappears, your files survive – but you need a new editor.

This is the A2 pattern: your data is autonomous, your tool is not.

Configuration (Minimal)

Download from obsidian.md. Open a folder. Start writing. No server, no Docker, no configuration.

For sync without Obsidian Sync, use Syncthing to sync the vault folder between devices.

Alternatives

  • Logseq – open source (AGPL), similar local-first approach, but outliner-based
  • Joplin – open source, Markdown notes with sync
  • Notion – cloud-only, A0/T0 – more features, less autonomy

Trajectory

Direction: stable with tension.

Obsidian’s core promise – local Markdown files, no lock-in – has held since launch. But the company increasingly promotes Obsidian Sync and Publish as paid services, which are cloud-dependent. The app remains free for personal use, but commercial use requires a paid license. No concerning license changes, but the closed-source nature means the community has no recourse if priorities shift.

Sources


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