Claude Code, with persistent memory.
Hydrate is a measured, auditable, on-premise memory layer for Claude Code. Four native hooks wire into the Claude Code lifecycle to inject prior context before every prompt and capture decisions after every session. No configuration. No cloud. Works on day one with your existing Claude subscription.
Four hooks, zero configuration.
Hydrate installs four Claude Code hooks. Each fires at a defined point in the Claude Code lifecycle. Together they form a complete memory loop: inject before the prompt, capture after the session, enrich before tools, observe after tools.
UserPromptSubmit Before every prompt Injects relevant prior decisions, session summaries, and pinned canon into the prompt context. Zero tokens wasted on things Hydrate already knows.
Stop After session ends Captures the finished session: extracts facts, decisions, and open threads, then writes them to the local store. Nothing lost between sessions.
PreToolUse Before every tool call Optionally enriches tool context with file-level or task-level memory before Claude Code touches the filesystem. Keeps large-project context sharp.
PostToolUse After every tool call Observes tool results to update in-session working memory. Useful for tracking which files changed and what decisions were made along the way.
One binary, one config file
Running hydrate setup drops four entries into your
~/.claude/settings.json and starts the local server on
localhost:24312. That is the entire setup. No daemon process
manager, no Docker, no cloud account required.
The hooks communicate with hydrate-server over localhost HTTP.
Session data stays on your machine: SQLite at
~/.hydrate/sessions.db, encrypted at rest with AES-GCM.
Nothing leaves the machine unless you are on Pro tier with a BYOK API key
and have opted in to fact extraction.
The same memory, wherever you work.
Hydrate does not care which assistant is asking. The on-prem binary answers context queries from Claude Code, VS Code Copilot, and any MCP client. Every fact captured on one surface flows to the others.
Claude Code
shippingNative hooks - UserPromptSubmit, Stop, PreToolUse, PostToolUse. Zero configuration. Works on day one with your existing Claude subscription.
Install guide →VS Code + Copilot
v1 launchVS Code extension registering an @hydrate chat participant plus three Language Model Tools. Same memory store as Claude Code - decisions captured in one flow to the other.
Copilot page →MCP server
shippingWorks with every MCP-aware client: Claude Desktop, Cursor, Cline, Zed, Gemini CLI, Mistral Vibe, your own agent. One endpoint, the same memory.
Integration guide →Your sessions never leave your machine.
On-prem binary
hydrate-server runs on your machine. There is no cloud
endpoint for session data. The free tier never makes an outbound
network call beyond licence validation.
Encrypted at rest
The local SQLite store is encrypted with AES-GCM. Keys are derived from your machine identity. Even if the file is copied, it cannot be read on another machine without the same key material.
Secrets scrubbed
The internal/scrubber package strips common secret
patterns - API keys, tokens, private key blocks - before any storage
or LLM processing. Credentials typed in a session are never persisted
or transmitted.
EU AI Act aligned
Hydrate ships an Article-mapped hydrate compliance report
subcommand. Every figure in the report is backed by a row in
hydrate_retrievals and can be reproduced with a single
sqlite3 query.
Install Hydrate today.
Hydrate is available for Claude Code on macOS and Linux. Free tier is unlimited local memory with no account required. Pro tier features (BYOK fact extraction, Team dashboard) ship alongside the public v1 launch.