From a curiosity-driven email project to a privacy-first suite for your inbox, Slack, and calendar — built with AI.
Visual Inbox started from a simple question: who am I actually communicating with? Not the words in each message, but the shape of the networks implicit in our emails, Slack messages, and calendar events. Who stays at the center? Who drifts to the edges? Which relationships are growing, and which are quietly fading?
This version was built from scratch in 2025, but the curiosity behind it goes back more than a decade. Here's the story.
In 2013, I had a curiosity I couldn't let go of: what would it look like if you could see the social network hidden inside your email? Not the messages themselves, but the structure — who you talked to, how often, and when. I asked two Master's students I was advising at the Media Lab, Daniel Smilkov and Deepak Jagdish, to help me build it. The result was Immersion: a web tool that mapped the relationships buried in your Gmail metadata using only the From, To, Cc, and timestamp fields. No message bodies. Just structure. Daniel wrote his thesis on Understanding Email Communication Patterns and Deepak wrote his on the Immersion platform itself.
The original Immersion demo video (2013)
Immersion launched on June 30, 2013, less than a month after the first news stories about NSA surveillance programs broke. The word "metadata" had suddenly entered everyday conversation, and most people had never stopped to think about what it meant. Immersion gave them a way to experience it firsthand — not as an abstract concept, but as a vivid, personal map of their own social life.
The experience was surprisingly emotional. People saw relationships they'd forgotten about, life transitions marked by shifting clusters of contacts, and the quiet drift of friendships they hadn't realized were fading. After analyzing his 13.4 years of Gmail and 216,507 emails, one Network World reviewer wrote that the tool revealed the shape of a life. Some users reached out to old contacts they hadn't written to in years after seeing them at the edge of their network.
The creators described it as being about "self-reflection, art, privacy, and strategy." Co-creator Daniel Smilkov told ABC News: "People are constantly emailing and messaging each other. We wanted to show people that email is a rich and underexplored data field." The TED Blog ran a behind-the-scenes feature, and WBUR (Boston's NPR station) described it as "a self-portrait made from metadata."
"For the press, Immersion was the tool that allowed you to PRISM yourself."
— César Hidalgo, in the Christian Science Monitor (July 2013)
The site crashed within days under the traffic. After relaunching on July 4th, it received over 60,000 visits in a single day. Hundreds of thousands of people used it. The Boston Globe wrote about what metadata says about you, Popular Science covered how it mapped relationships, and NBC News reported on the 70,000+ visitors in its first week. A sample of the coverage:
Two videos from other creators who explored Immersion at the time:
Immersion is now defunct as a hosted service, but the code remains available as open source. Anyone is welcome to download, fork, and build on it.
View Immersion on GitHubAfter Immersion, I assembled a new team to build something more ambitious: Open Teams. Where Immersion was a personal mirror, Open Teams was a team-level instrument. Multiple members could log in at once, and the system would stitch their individual networks into a shared view of the whole team.
The project was built by three people, each bringing a different lens. Jingxian Zhang, a Master's student at the MIT Media Lab, handled the engineering — her thesis, MITeams: Quick Organizational Mapping by Combining Email and Survey Data, documents the technical architecture. Xiajiao Chen, a graphic and UI/UX designer, shaped the interface. Diana Orghian, a psychologist and postdoctoral researcher in my group, designed the questionnaires and psychometric assessments. They refined the tool together through several iterations.
Open Teams went beyond network visualization. It added several psychological assessments — personality inventories and collaboration style surveys — that let teams overlay psychological profiles onto their interaction patterns. You could see not just who was talking to whom, but which personality types were bridging groups, where communication silos were forming, and how information flowed (or didn't flow) across the team. It was a tool for collective self-awareness.
Open Teams: visualizing team dynamics and personality types
Open Teams was a substantially larger engineering effort than Immersion, requiring server-side coordination for multi-user sessions, a survey infrastructure, richer data models, and a more complex frontend. The project ran for a few years before going offline in 2019. As with Immersion, the code remains open source.
View Open Teams on GitHubAfter Open Teams went offline in 2019, I missed it. But I also came to see that the old projects had always been incomplete: both Immersion and Open Teams only looked at email. Modern professional life doesn't live in one place — it flows across inboxes, Slack conversations, and calendar invites. For a mirror to reflect the shape of our communication, it had to look at all of them.
So in late 2025, I built Visual Inbox from scratch — this time as a suite of three tools, with a broader scope and a fundamentally different architecture than its predecessors. It treats your professional network as a multi-channel whole: Visual Email maps the social graph hidden in your Gmail metadata. Visual Slack turns a Slack workspace export into a network of channels, mentions, and threads — revealing the informal org chart that forms inside any team. Visual Calendar visualizes your time: the people you meet with, the rhythms of your weeks, the hidden patterns in how you spend your days. Three complementary views of the same life.
Immersion and Open Teams processed your data on our servers. Visual Inbox processes everything locally in your browser. Your email metadata, calendar events, and Slack exports never leave your device. There is no backend database, no server-side storage, and no way for us to access your data. This is privacy-preserving by design, not by policy.
To formalize that commitment, Visual Inbox went through Cloud Application Security Assessment (CASA) Tier 2 verification. CASA is an independent security review program managed by the App Defense Alliance — a coalition founded by Google to raise the security bar for applications that access user data. Tier 2 certification means:
This is a level of scrutiny that most personal tools never undergo. It matters because the data Visual Inbox works with — your communication patterns, your relationships, your calendar — is deeply personal. You deserve to know that it's being handled carefully.
Across all three versions of this idea — Immersion, Open Teams, and now Visual Inbox — the core motivation has stayed the same. It's not about surveillance, productivity hacking, or analytics dashboards. It's about seeing yourself.
Your inbox — together with your Slack conversations and your calendar — is one of the most complete records of your social and professional life. It captures where your attention goes, how your relationships evolve, and what the shape of your world actually looks like — not the shape you imagine, but the one that emerges from thousands of small decisions about who to write to, who to meet, and who to leave for later.
Visual Inbox is a tool for that kind of reflection. I hope it helps you see something about your own life that surprises you, or reminds you of someone you've been meaning to write to.