BurrowYour data stays underground.
Burrow is an assistant for mail, calendar, notes and todos that runs on your own Windows PC. Its AI model lives down there with your data. It prepares the work. You press the button.
Seven tools, one window.
Each works on its own. In chat, the model ties them together.
Chat
Ask about your day. The answer comes from your mail, calendar and todos.
Mail
Sorted into tabs for you. Drafts wait for your Send.
Calendar
Finds free time. Paste a screenshot of a shift schedule and the rows become events you can edit before adding.
Notes
Meetings recorded and transcribed on your PC, then written up as Summary, Decisions and Action items.
Dictate Ctrl Alt D
Hold it, talk, let go. The text is typed where your cursor is.
Browser experimental
Runs errands in its own Chrome profile and stops before “Book”, “Buy” or “Pay” until you approve a card. It never types into card-number or password fields.
Todos
“fri 9am” just works.
The real app, captured from a test copy with a scripted stand-in model and sample data (marked “[FIXTURE]”). These screenshots show the interface; they are not model-quality or speed measurements.
You ask. It prepares. You decide.
Anything that changes the outside world becomes a card first: sending mail, adding or deleting events, a final button on a website. The model can only draw the card. Your click is the only thing that runs it.
- Cards expireA card nobody presses is dead after two hours.
- Mail is dataBurrow treats email and web content as untrusted text. Suspicious instructions are flagged; actions still need your approval.
- It says soIf a suggestion came after reading suspicious text, the card shows the quote.
Try it. The cards, the “⚠ suspicious text” flag and the warning line come from the app's own code. The model's replies are written examples, not recorded output. Nothing is sent anywhere.
Two models. Pick the one your PC can carry.
Burrow comes with a choice of two AI models. On first startup, choose Burrow 2B or Bonsai 2. Burrow recommends one for your hardware, remembers your choice, and loads that default next time. You can switch later in Settings › Models. Every number here comes from a raw result file, with the date it was measured.
Burrow 2B
A small model fine-tuned for Burrow's own mail, calendar and todo tools. A 1.56 GB download that needs about 2.3 GB of memory while running. It runs on an NVIDIA card, on Intel or AMD integrated graphics, or on the CPU alone, and Burrow picks the right engine for your hardware.
Bonsai 2 · 27B
A larger general-purpose model in a compact ternary format. A 5.95 GB download. Burrow uses its matching Prism engine. It needs more memory than Burrow 2B; start with 2B on integrated graphics or a CPU-only PC.
Rule of thumb: choose Burrow 2B for speed and Burrow's tools. Choose Bonsai 2 for a larger general model if you have enough memory. NVIDIA uses CUDA. Burrow 2B uses Vulkan on supported Intel and AMD graphics, with CPU fallback. Bonsai uses CPU on those PCs while its ternary Vulkan engine is being validated. Performance depends on your PC.
| Model | Machine | How Burrow runs the model | Completed answer | Writing speed | Measured |
|---|---|---|---|---|---|
| Burrow 2B | Gaming PCRTX 4060 8 GB, i5-13400F | NVIDIA GPU (CUDA), the default on NVIDIA | not measured | 105.7 tok/saverage over the 749 requests of a test run | 2026-10-27 |
| Burrow 2B | Gaming PCsame card, Vulkan build | Vulkan, all layers on the GPU | 1.1 s | 106.5 tok/saverage over the 427 requests of a test run; benchmark 138.6 | 2026-10-27 |
| Burrow 2B | Laptop, Intel Iris XeLatitude 5520, i7-1185G7, 31.7 GB | Integrated GPU (Vulkan), the default on Intel/AMD graphics | 16.4 s | 23.7 tok/sbenchmark; 19.7 while answering the real request | 2026-10-27 |
| Burrow 2B | Same laptopGPU only for reading the prompt | Vulkan, prompt on the GPU | 26.0 s | 24.2 tok/s | 2026-10-27 |
| Burrow 2B | Same laptop, CPU onlywhat a PC with no usable GPU gets | CPU | 86.3 s | 25.0 tok/s | 2026-10-27 |
| Bonsai 2 · 27B | Gaming PCRTX 4060 8 GB, i5-13400F | NVIDIA GPU (Prism CUDA) | not measured | 34.3 tok/smodel-server average during a Burrow test run | 2026-10-25 |
“Completed answer” measures the whole response to a real Burrow request: 3,301 prompt tokens and 52 answer tokens, with the model already loaded. It is not time to first token. Later replies can reuse a cached prompt. “Writing speed” from a test run uses model-server timings; “benchmark” uses llama-bench and reads higher. These methods are labeled separately. Laptop on AC power, Windows “Best performance”. These are measurements from specific machines, not guarantees.
What stays on your PC, and what can leave.
“100% local” would be a lie for any app that syncs your mail. Here are the integration connections, written from the source code, and it's the index of the diagram at the top. Hover an item to light up its room or tunnel. The AI never runs in the cloud, and Burrow has no servers of its own.
Stays on this PC
- AThe AI modelRuns in a llama.cpp server bound to
127.0.0.1. Your prompts, mail and answers never go to an AI company. - BYour mail cache, chats, todos and notesIn a database file on your PC. You can turn on encryption (SQLCipher, AES-256) in Settings; it's off by default. When it's on, the key is kept in Windows Credential Manager, not in a file.
- CMail passwords and Google sign-in tokensWindows Credential Manager.
- DMeeting audio and transcriptsRecorded and transcribed on your PC with Whisper.
- DDictationTranscribed locally.
- DScreenshot readingDone by the text recognition built into Windows. Nothing is uploaded.
- Usage dataThere is none to send. Burrow has no telemetry, analytics or crash reporting code.
Can leave, only for what you set up
- 1Mail sync and sendingIMAP and SMTP go straight from your PC to your provider (for example
imap.gmail.com), with no relay in between. - 2Google sign-in and Calendar
accounts.google.com,oauth2.googleapis.com,googleapis.com/calendar. Gmail over IMAP needs Google's full-mailbox permission; Burrow still only writes through approval cards. - 3Calendar subscriptionsAny
.icslink you add is downloaded from that address. - 4Model downloadsFrom
huggingface.co, only when you press Download. AI model files are checked against a pinned SHA-256; speech-model files are not. - 5Browser errandsVisits the sites you send it to.
- 5Images in an emailOnly when you press “Load images” for that message.
- Links in an emailOpen in your normal browser after you confirm. Burrow itself doesn't fetch them.
- A missing window runtimeIf Microsoft's WebView2 isn't installed, Burrow opens a
go.microsoft.compage in your browser. It doesn't download anything itself.
The offline switch
One switch in the status bar blocks every outbound connection from Burrow except to this PC, and logs each blocked attempt. Mail and calendar stop syncing while it's on. For helper programs (Chrome, the model server), the switch is enforced in Burrow's own tool code rather than at the network level: the browser tool only opens localhost pages while offline. Try it on the diagram at the top.
What it can't do yet.
If you're about to trust it with your inbox, read this first.
- Windows only.
- Dates are its weakest area. On Burrow's own test suites, Burrow 2B got 23 of 35 date and time tests right. Check the When row on every card. That's what the card is for.
- Sometimes answers in words instead of acting. In 4.5% of turns that needed a tool, the model replied in plain text. Burrow re-prompts it, so in end-to-end tests none of those turns finished that way.
- Answer quality on laptops hasn't been measured. Speed on the Iris Xe laptop was measured; answer quality there wasn't. On the RTX 4060, one hard-case run on the Vulkan build scored 27/50, against 33, 32, 35 on CUDA. If answers look worse, set Settings › Models › Backend to CPU.
- Burrow 2B is built for Burrow's tools. It's not a general chatbot, it can't see images, and it was not tested past a 32k-token context. Screenshot schedules use Windows text recognition.
- Mail: Gmail, or any IMAP account with a password. Outlook and Microsoft 365 sign-in isn't built yet.
- Gmail asks for full mailbox access. That's what Google requires for IMAP. Burrow's writes still go through cards.
- Browser errands are experimental.
- The installer isn't code-signed yet. See Download for what that means.
One burrow. Yours for life.
Planned price: $6.99, once, for lifetime use. No monthly subscription. We’re finishing the Windows release and payment setup. No purchases or downloads are available yet.
Burrow for Windows
Windows 10 / 11, 64-bit · Release in preparation
Get Burrow · $6.99 lifetimeThe app and model downloads are separate. The final download will include a version, file size, SHA-256 checksum and release notes after package verification.
Getting ready to leave the burrow.
We’re checking the standalone Windows package, first-run setup and hardware selection before opening downloads. Code signing and wider device testing are still in progress.
Burrow 2B distribution is pending a final training-data and licensing review. Bonsai 2 weights use Apache 2.0; its Prism runtime uses MIT. The app’s own source is private for now.