Mnemosyne OS


Mnemosyne OS — Free Download. Desktop OS

Mnemosyne OS is a desktop operating system built around memory as its core primitive, not an afterthought bolted onto a chatbot. It watches the folders you already keep, turning documents, notes, PDFs, images, captured web pages and agent transcripts into searchable vaults stored on your own drive. Retrieval combines semantic and lexical matching on your machine, so search keeps working with the network cable unplugged. An MCP server, connectors and a spatial canvas give agents and people a shared, persistent memory surface rather than a fresh session each time.

5.0(1 ratings)
File size: 185 MB
The latest version of Mnemosyne OS is: 1.4.5
Operating system: Windows, Mac OS, Linux
Languages: English, Spanish, Portuguese, German, French, Chinese, Russian
Price: $0.00 USD (Freemium product ($70 or free version))
  • Folder watching and memory ingestion. Mnemosyne OS monitors directories you select and continuously converts their contents into structured memory. It processes documents, notes, PDF files, images, captured web pages and transcripts generated by coding agents. Each item becomes a searchable record inside a vault, and new or changed files are picked up automatically as part of the ongoing indexing cycle.
  • Vault partitioning. Memory is divided into vaults, each representing one area of life such as code, research, journal or work. Every vault carries its own protection level and consent boundary. Two vaults remain separate unless an explicit rule connects them, which keeps unrelated material from bleeding into the same retrieval pool.
  • Hybrid retrieval engine. The retrieval engine runs an in-RAM, decrypted vector cache quantized to int8 for scale. Approximate nearest neighbour search is unioned with exact term matching, then a final re-rank pass orders the candidates. Semantic and lexical signals combine so both conceptual queries and literal keyword lookups return relevant memories.
  • Embedding engine with provider chain. Embeddings are produced through a priority-ordered chain of providers: cloud services, local ONNX models or Ollama. If a provider fails, the engine reports the failure instead of returning a null vector, ensuring a failed embedding never becomes an invisible, unreachable memory.
  • Spine engine and taxonomy. Every memory is classified by its semantic nature, its spine, plus associated tags. The taxonomy exists as data rather than hardcoded logic, so new categories can be introduced without modifying program code. Classification shapes how memories are grouped, filtered and surfaced during retrieval.
  • Dream State consolidation. A two-speed consolidation system rereads and reconnects memories during rest phases. A fast tier extracts facts while the system is in use, and a heavier tier runs at idle or overnight to resolve contradictions and link sessions together. Consolidated results are appended alongside raw retrieval rather than replacing it.
  • Adaptive RAG gearbox. Context selection adapts to the model tier in use and the chosen thinking mode. Top-k selection, maximal marginal relevance and low-discrepancy sampling scale the amount and diversity of injected context instead of pushing every candidate into the prompt.
  • Multimodal chat. Conversation accepts text, voice and file input, with live retrieval from your own vaults. Answers draw on stored memories during the exchange, so the dialogue reflects material the system has indexed rather than only the current session.
  • Voice assistant with STT and TTS. Speech recognition and synthesis run as independent engines. Small STT models operate in-process, larger ones run in an isolated GPU or CPU sidecar, and TTS can use system, cloud or local voices with sample-accurate playback. Without an NVIDIA GPU the system falls back to CPU instead of blocking.
  • Theia image memory. Named for the Titaness of sight, Theia embeds images from your vaults locally using SigLIP 2 and recalls them in chat. Matches surface as thumbnails through three fused channels: semantics, pixel palette and emergent categories. The feature is off by default, and a cold or still-indexing engine states its condition rather than reporting no matches.
  • Neural Map. Memory is drawn as a navigable graph where nodes represent memories and edges represent measured semantic links. The layout and link strength can be tuned live, giving a spatial view of how stored material relates across vaults and sessions.
  • MnemoHub cartridges. A catalogue of third-party cartridges provides real applications with their own declared permissions. Cartridges are signed by a sovereign wallet and verified client-side before any render, and an SDK exists for building additional ones.
  • Sovereign wallet and Engramm. A local sovereign wallet drives licensing, verified on Base, along with the pseudonym and cloud credits. No account, password or gas fees are involved in the process.
  • Spatial canvas interface. Widgets live on a 2D canvas spread across several desktops rather than in stacked tabs. Chat, vaults, notes, the neural map, a to-do list, an agenda, an image studio, a PDF reader, a capture browser and a conversation recorder all occupy positions on that canvas, where placement carries meaning.
  • Agent control room. An MCP server ships with the system so Claude Desktop, Claude Code and other MCP clients draw on the same memory. A bridge connects VS Code and Cursor, connectors read what coding agents write to disk, and status cards can be pinned to the canvas. Warnings appear when two agents work in the same git tree.
  • IPC channel layer. Five hundred and six Zod-validated IPC channels connect every engine to the interface. The channels are auto-generated and checked by a drift test on every build, keeping engine and UI contracts aligned as the system evolves.

Mnemosyne OS is developed by XPACEGEMS LLC and has been built as a memory-first desktop environment rather than a conventional note application. The project is published with an MCP server, an SDK and a cartridge SDK available on npm under the MIT licence, while the core desktop system ships for Windows, macOS and Linux. A one-time perpetual licence of seventy dollars unlocks local neural voices, heavy local OCR and premium MnemoHub cartridges, with free use available alongside it. Documentation covers concepts, architecture, governance and design decisions, and a technical whitepaper describes the Resonance Engine and its approach to memory retrieval. The system is written primarily in TypeScript and Rust, combining a web-based interface layer with native engine components.

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