nohmitaina

nohmitaina (脳みたいな, "brain-like") is a macOS desktop editor built by simochan at Hikutas, Inc. in Tokyo. It combines a serious Markdown writing environment with an AI-powered background process that extracts concepts from your notes, generates a personal wiki, and scores ideas using cognitive science models — all stored locally as plain Markdown files. The tool is currently available as a free download for Apple Silicon Macs, with add-on features in preparation.

What It Is

nohmitaina sits at the intersection of personal knowledge management and AI-assisted thinking. Unlike traditional note apps that let you search and re-read, nohmitaina runs a scheduled background process called "Dream" that extracts concepts from everything you've written, drafts wiki pages, draws links between them, and re-scores each concept's importance over time. The result is a living knowledge base that surfaces what matters and lets the rest quietly fade — mirroring how human memory actually works.

The Science Behind the Scoring

The tool is explicitly built on three cognitive science pillars:

• Two-strength memory model (after Robert A. Bjork): retrieval strength (how easy it is to recall now) and storage strength (how deeply it has stuck) are tracked separately.
• ACT-R base-level activation (Anderson & Lebiere, 1998): every reference and revisit contributes to a concept's recall score, which decays with time using the formula B(t) = ln(Σ tᵢ⁻ᵈ) with d = 0.5.
• Surprise as a signal: new concepts are checked against everything already in the wiki; genuinely novel angles surface, familiar ones stay quiet.

The architecture also adds a fourth layer — "Core" — on top of Andrej Karpathy's described Raw/Wiki/Schema LLM-wiki model. Core is a compressed representation of the user's current thinking that is always in context for AI conversations.

How the Four-Moment Workflow Operates

The daily loop has four distinct moments:

• Morning (Write): A full Markdown editor with tables, math, Mermaid diagrams, code blocks, and link cards. Voice input is transcribed via Whisper. A "MemoOnly" mode keeps private entries out of AI processing.
• Night (Dream): On a quiet schedule, the system extracts concepts, drafts wiki pages, draws links, and re-scores everything. Notes and wiki pages remain plain Markdown on disk, readable in any editor or IDE.
• Anytime (Talk): AI dialogue opens with Core concepts already in context. The model can search the broader wiki when needed. Every 10 turns, the dialogue itself is folded back into the wiki.
• Sometimes (Look Back): A concept map view shows themes, connections, and high-surprise findings laid out visually.

Local-First Architecture and What Was Deliberately Left Out

All data lives on the user's disk as plain Markdown. The tool does not run a cloud service for notes. API calls send only the text the model needs; the maker states that Anthropic and OpenAI API policies do not train on API content. Users can run the tool through Claude Code or the Codex CLI without a billable API key, or bring their own provider key.

The maker explicitly chose not to build: an all-in-one workspace, a bidirectional linking tool requiring manual [[brackets]], a daily-journal format, or a cloud storage layer.

Update: Version 0.1.6 (May 2026)

The changelog on the homepage shows active development with three releases in May 2026:

• 0.1.6 (2026-05-20): Editor document tabs with macOS titlebar integration; local Whisper model settings.
• 0.1.5 (2026-05-18): Manual Recall from selected text; rectangular selection and macro record/replay; more resilient Dream processing.
• 0.1.4 (2026-05-11): Multi-workspace activation; startup catch-up for missed Dream runs; scoring and Core refinements.

The tool launched on Product Hunt and is currently macOS-only (Apple Silicon), with Windows and Linux described as "technically possible" when demand warrants, and mobile read access planned as part of the forthcoming Sync add-on.