Σ  ·  the sum of everything you know

Let AI work with the sum of
everything you know.

Sig captures what never got written down — the meeting decisions, the verbal commitments, your read on what actually happened — and keeps it on your machine. Every AI tool you already use gets dramatically more useful because it finally has real context to work from.

Download for macOS See how it works →
macOS· Windows· Linux
macOS 13+ Windows Linux works with Claude
No account to create Nothing leaves your machine without your sign-off Uninstall leaves your files on disk
Same AI, different starting line

The agent didn't get smarter. It finally has context.

Every AI tool you use is capable. What it's missing is everything that happened in your week. Here's the difference that makes.

Without Sig
  • "Who is Bailey, and what did we decide?" — every session starts by re-explaining your world.
  • Generic output, because the model is guessing at specifics it was never given.
  • The verbal commitment, the hallway decision, the pattern across three calls — invisible. Gone by Monday.
  • Context lives in your head — and leaves when you do.
With Sig
  • It already knows your people and projects — no re-briefing, ever.
  • Specific, grounded answers, because it's drawing from what actually happened.
  • "Bailey raised this same concern twice this month" — the connections you'd have missed, surfaced.
  • Context lives in plain files you own — and compounds every week.
What you'll do Monday morning

Four things. That's your whole workflow.

Sig doesn't ask you to change how you work. After a meeting, you talk through what happened. Before a call, you ask what's open. At the end of the day, you wrap up. That's it.

Sig — Home
⌘K
Good morning, Adam.
What do you want to do?
+ any skill you've installed — run from here or from the Skills tab
1

Download & open

An app, not a setup script. No terminal, no config files. About fifteen minutes from download to your first capture.

2

Talk after a meeting

Two minutes describing what happened — the facts, then your read on it. Sig files both as plain markdown.

3

See what gets saved

Every write is shown in plain language with the exact file. Point any AI you use at it and watch it start from everything.

When you're ready, Sig helps you share approved knowledge with your team — deliberately, never automatically.

Team knowledge

Share once. Everyone's briefed.

One click in Sig sends a piece of knowledge to your team. Git handles the sync in the background — your teammate's Sig has it as context the moment they open it. No Confluence page. No Slack thread. No re-explaining.

Skills travel the same way.

Build a 1:1 prep skill, a weekly update template, a customer call debrief. Share it with your team in one click — they install it in seconds. The methodology travels without the training session. Git handles the rest; your team never sees it.

1:1 prep
from Adam  ·  34 installs
Installed
Weekly update
from Adam  ·  28 installs
Installed
Customer debrief
from Jordan  ·  12 installs
Install
Your files, your format

Your notes stay yours — forever.

Plain markdown files on your machine. Sig builds the context. Every agent you trust consumes it. Leave tomorrow and your memory is still yours, in a format that's been readable for thirty years.

Sig Files — your notes as plain markdown on disk

Plain files you can open in any app

Open them in Notes, Obsidian, or any text editor. Point any AI tool at them. The format has been readable for thirty years and always will be.

Private by default, shared by choice

Nothing leaves your machine until you review it and approve it. The personal layer — your thinking — stays yours, always.

Works with the AI you already have

Claude, ChatGPT, Gemini (GitHub Copilot coming soon), plus local models. Sig is the context layer under your agents — not another subscription to choose between.

Why Sig

Four things no other tool does at once.

Enterprise search indexes what's documented. Note apps wait for you to write. Chatbots start from zero. Sig is the layer underneath all of them.

Captures what no agent can find

The meeting with no minutes, the verbal commitment, the task outside the tracker. Sig creates the record that never existed.

Your thinking, not just the facts

Your interpretation, your read between the lines, your debrief. The layer that makes your work good — captured and kept distinct.

Works with the AI you already have

Claude, ChatGPT, Gemini — GitHub Copilot coming soon. Not another subscription — the context layer that makes whatever you already use dramatically better.

Private by default, shared by choice

Everything lands on your machine. Your team sees only what you review and approve — explicitly, never automatically.

Context density over time
Week 1
18%
Week 2
34%
Week 4
58%
Week 8
82%
Week 12
96%
By week twelve, your agents know your people, your projects, your patterns. Tribal knowledge no one else has captured — and every agent you run draws from it.
Gets sharper every week

Week 1 is decent.
Week 12 is yours alone.

The agent didn't change. The context did. Sessions that used to produce generic output start producing specific, grounded responses — and keep going.

The honest truth about week 1
Closing the mental loop. Two minutes after meetings, offloading your RAM into Sig. It isn't a documentation chore — it's a way to empty your head so you don't carry the stress of "what did I forget." The payoff hits in week two, when your agent surfaces a verbal commitment you would have lost.
The privacy model

Private by default. Always.

Your thinking layer is the one every great operator has always kept. Sig is the first tool built to support it honestly — not to index it, summarize it, or ship it off.

What Sig isn't

Clarity about where we belong. Enterprise tools do enterprise jobs well — we fill the gaps they were never designed to reach.

  • Not a note-taking app. Notion and Obsidian ask you to impose structure. Sig asks you to talk about your work.
  • Not enterprise search. Glean and Copilot index what's already documented. Sig captures what never was.
  • Not a chatbot. ChatGPT starts from zero every session. Sig is what makes it start from everything.
Our promise

Three commitments, plain English

We don't have a security page written in the passive voice. We have three sentences a non-lawyer can hold in their head.

01

Everything you capture lands on your machine as plain markdown. No server copy by default.

02

Your personal layer — your thinking — is never synced, never trained on, never shared without your explicit approval.

03

When you do share, it's you reviewing the exact text with AI assistance, then clicking publish. That's the whole mechanism.

From early users

The moment it clicks usually happens in week two.

Sig is in early access. Here's what the first users have been telling us.

"

I manage a team of twelve. Before Sig, my 1:1s started with five minutes of figuring out where we left off. Now I ask what's open with each person before I walk in — last three conversations, open commitments, the thread I'd have otherwise lost. My team thinks I have an incredible memory. I don't. I have Sig.

AR
Adam R.
Sr. Director of Engineering
"

I work across six client engagements at once. The context that falls between them — the offhand comment in a steering call, the thing the VP said after the meeting ended — that's where the real work lives. Sig is where I put it.

MC
Marisa C.
Sr. Innovation Consultant
"

The moment it clicked was when I described a technical decision in standup and my AI already knew the constraints — because I had talked through it in Sig the week before. I stopped re-explaining my own codebase.

MT
Morit T.
Senior Full Stack Developer
"

What sold me was seeing the markdown files. My context isn't locked to their app. If Sig disappears tomorrow, my memory is still mine — that matters more than any feature.

DK
Devon K.
Principal Designer
"

We move fast and the relationships are everything. I used to lose the thread between conversations — what someone needed, what I had committed to. Now it's all there before the next call. That's the whole game in this business.

AK
Andrew K.
Roc Nation Sports
early users at Blindside GmbH Panora.cx Peninsula.co
Questions, answered

The things people ask before they download.

01My company already has an enterprise AI tool.
Enterprise tools search what's been formally documented and shared. They have no answer for undocumented work — the meeting with no minutes, the verbal commitment, the task outside the tracker — and no layer for your thinking. Sig fills both gaps. They're complementary, not competing.
02Doesn't this mean keeping context outside company systems?
Sig is for personal working context and tribal knowledge — the kind every effective knowledge worker already carries in their head. Not company decisions or company documents. When you're ready to contribute it to the team, you do so explicitly. Nothing leaves your machine without a deliberate choice.
03Why pay for this when I can just use ChatGPT?
You can — but ChatGPT starts from zero every session. Sig is what makes ChatGPT, or any agent, start from everything you've built. The agent isn't the product. The context is.
04This sounds like a lot of work to set up.
About fifteen minutes. After that, it fits the workflow you already have — you describe what happened after meetings you're already in. The context builds itself from your normal work week. No terminal, no config files.
05My company controls which AI tools I can use.
Sig works with whatever you're already approved to use — Claude, ChatGPT, Copilot, Gemini. It's the context layer under any agent, not a replacement for the agents your company has approved.

Download Sig free.

Public beta for macOS, Windows, and Linux. Try it after your next meeting.

Download for macOS All downloads
macOS· Windows· Linux
no account · uninstall leaves your files on disk