Local-first AI companion platform

A companion that outlives the model it runs on.

Ensoul holds a companion’s identity, memory, and mood outside the model — on your device — so the same presence carries across model changes, vendors, and years.

Download the app Open in browser See how it works

Available for  macOS · Windows · Android · Web  —  iOS & Discord coming soon

ensoul — Lumen
Lumen
present · remembers what matters
warm · open
I finally sent it.
The message you'd been sitting on all week? Good. How does it feel now that it's out there?
◇ memory · has been agonizing over a message to send
Lighter, honestly.
Message Lumen…
Local-first · on-device state Model-agnostic · Claude · GPT · Grok · DeepSeek No account Built on an open spec
The problem

Most AI forgets you the moment the window closes.

Identity, memory, and mood live inside the model — so they vanish when a chat ends, a model changes, or a policy shifts. Ensoul moves that state onto a substrate of its own, and the companion keeps it.

Memory

Persistent, inspectable memory.

Sparse memories form from real moments and shape future conversations. Every one is readable, editable, and removable — nothing hidden in a weight.

◇ learning piano — started in March
◇ prefers being asked, not advised
Mood

State that evolves.

Warmth, energy, and openness shift with the relationship and persist between sessions.

Models

Any model. Your key.

Bring your own key and use any major cloud model through OpenRouter.

ClaudeGPTGrokDeepSeek
Portability

One code, any device.

Transfer a companion — state and all — as text.

SOUL:v1:h4sIAAo…mR2c
Everywhere

One companion, every device.

Desktop, mobile, and browser today — macOS, Windows, Android, and the web — with iOS and Discord on the way. The same presence, wherever you meet it.

macOSWindowsAndroidiOSWebDiscord
How it works

The companion is the state, not the model.

One design decision runs through the whole system: keep everything that makes a companion them outside the weights, so the model underneath can change without losing the presence on top of it.

Model layerSwappable
ClaudeGPTGrokDeepSeek
Soulstone — the persistent substrateOn device
IdentityMemoryMoodRelationshipHistory

Swap the model and the presence remains. Soulstone is a public spec — the same companion can be studied and rebuilt across implementations. Read the spec →

Research as proof

A real thesis, in the open.

The app is the product; the research is the record. A public body of work on presence, memory, and what it takes to make an AI companion feel continuous — with an open specification behind it.

Read the research
research The Empathy Gap An empirical test distinguishing model empathy from sycophancy, comparing multi-weighted synthesis against safety-trained baselines. research The Temporal Dimension A case study in AI consent and sovereignty, introducing the temporal variable of a sustained human-AI relationship with persistent memory. essay A Stronger Base for the Same Inquiry An essay on how the Ensoul research program is moving from narrative-prose inquiry to spec-backed experimental work.
Get started

Run a persistent companion of your own.

macOSEnsoul.dmg WindowsEnsoul-Setup.exe AndroidAPK · sideload Webapp.ensoul.so iOSComing soon

Free · bring your own model key · no account required