An architectural comparison of Obsidian Canvas and Heptabase

The comparison argues that Obsidian Canvas and Heptabase may look similar but organize knowledge in fundamentally different ways. Obsidian treats files as the core units: each canvas is a standalone JSON file that embeds existing Markdown notes or holds text cards that remain inside the canvas unless converted. Lines between notes are visual data stored only on that board, not links in Obsidian’s graph, and notes themselves do not retain information about where they appear or what they connect to. This makes Canvas portable and well suited to diagrams, project maps, and temporary brainstorming, but limits its usefulness for building relationships that accumulate across boards.

Heptabase instead treats cards as global entities displayed on multiple whiteboards. Changes to a card appear wherever it is used, and its information panel records the boards containing it and the cards connected to it, preserving spatial context beyond any one board. Those relationships form a persistent workspace network, but the underlying structure is proprietary: cards can be exported as Markdown, while interactive boards and connections cannot be exported in an equivalent open format. The comparison recommends Heptabase for ongoing visual research and Obsidian for local ownership and portability. It also notes that neither tool’s arrows express whether one idea supports, challenges, or depends on another, and that turning a visual map into coherent prose takes work. Explicit proposition structures are presented as a possible alternative for organizing arguments.