Ambient AI memory platform, Cincinnati, Ohio
Pieces is an ambient AI memory platform, founded in Cincinnati, Ohio in May 2020 by Tsavo Knott and Mack Myers. It remembered your work on your computer so you could draw from that history on demand. It shipped the Desktop app, the primary UI for macOS, Windows, and Linux, and PiecesOS, the always-on background service and engine behind the system, plus plugins for the popular browsers and developer tools and a web application for team admins and configurations. It reached over 110,000 registered users across more than 200 production releases.
Mack served as Chief Product Officer and Chief Operating Officer from incorporation in May 2020 until September 2026. He owned and oversaw all front-end development and the shared module architecture and SDK that powered the plugins. He was the main product designer, working closely with the CEO, and the primary interface between customers and the company.
Pieces raised $26M over 6 years. It began with a $180,000 pre-seed SAFE in December 2020, ran through further SAFEs and convertible notes into a priced Seed, and reached a $44M post-money valuation at the Series A in April 2024, led by Drive Capital. More SAFEs and notes bridged the gaps on either side of it.
That money paid for the Desktop app, the primary UI for macOS, Windows, and Linux, and PiecesOS, the always-on background service and engine behind the whole system, plus the plugin suite and a cloud-based team management portal for creating teams and orgs. Admins got centralized model management, memory settings, and the rest, deployed down to the Desktop app and PiecesOS in real time. More than 200 production releases in under four years, drawn from thousands of builds.
Pieces remembered your work on your computer, so you could draw from that history on demand. It ran in the background and turned what had already happened into something you could search, ask about, or use to get the next thing done.
Underneath all of it was a memory graph. Work events, people, topics, tags, descriptions, summaries and conversations, all connected to each other instead of filed away in separate piles. A single person would accumulate hundreds of conversations, thousands of summaries, thousands of people and topics, and hundreds of thousands of work events. Keeping that fast, and building an interface someone could actually move through it with, was most of the engineering problem. The desktop client stayed reactive while hundreds of thousands of those events moved over real-time websockets.
PiecesOS also carried an MCP server, so somebody's own graph could be reached from Cursor, Claude Desktop, Claude Code, Codex, Antigravity, or any other MCP-enabled client.
They reached over 110,000 registered users, with monthly active devices peaking around 40,000.
Ninety-three people were employed over the six years, across ten countries, with twenty-five on payroll at the peak. That ran 2,310 days, from incorporation to the day the team was let go. Mack was there for all of them.
Four people were the constant across the six years: Mack, his co-founder Tsavo Knott as CEO, Mark Widman as CTO, and Nathan Courtney leading DevOps, CI/CD and deployment engineering. Between them they had a hand in very nearly every release the company shipped, and most of what follows was done alongside them. Reviewing each other's work, arguing a design into better shape, talking someone out of the wrong solution. None of that gets its own line below, because it ran through all of them.
Lead engineer on the Desktop app, the primary UI. PiecesOS was the always-on background service and engine behind the whole system. The client carried its own database, so the work ran well past the front end. 3,687 commits over 43 months, and the largest single contributor by 5.7 times over the next engineer.
He was the main product designer, working closely with the CEO on nearly every product surface. Hundreds of Figma designs went through repeated iterations for usability, efficiency, consistency, convention, and intuitiveness. He designed, built, and measured desktop onboarding to raise new-user conversion and shorten the time to a first useful moment.
The client had to stay reactive while hundreds of thousands of memory-graph events moved over real-time websockets. He also designed, built, and measured the copilot chat for real-time conversations across Google, OpenAI, Anthropic, xAI, and Microsoft, including cloud models and downloadable local models. He wrote production algorithms for activity consolidation and de-duplication, batched work-activity grouping, MCP search and retrieval, an onboarding loop scored against a few heuristics, and a server-UI coupling that kept PiecesOS alive through crashes and restarts.
The work was design, build, maintain, demo, sit with the people using it, measure what they did with it, then help market and write about it. Across 2,797 pull request and issue titles, the work clusters in four places. The AI copilot and the LLM surfaces, app UI and onboarding, search and organization, and summarization. Almost all of it in Dart and Flutter.
Company-wide the record comes to 12,984 commits in 137 repositories, 1,688 pull requests at a 93% merge rate, 2,563 reviews for 41 colleagues, and 1,109 issues opened with 802 closed. 98.2% of it sits in private repositories, so a public profile shows almost none of it. The median pull request merged in 1.7 hours.
The totals matter less than the shape of them. He reviewed more than he authored through most of those years, and his own output still went up the whole time, hitting 637 pull requests in 2025 against 714 reviews of other people's work. In 82 of those 137 repositories the first commit landed within a week of the repository being created. Fifteen were worked for two years or more, and the top five hold 60% of all commits.
Mack built a shared client SDK so copilot chat, settings, and saved materials were one experience across the Desktop app, browsers, and IDEs, and so those surfaces had a single source to maintain. The plugin hosts were mostly TypeScript, so those modules shipped as a compiled web app served by PiecesOS. 4,077 commits across the copilot module, core connector, workstream activity, saved materials, settings and the platform client SDK, from 2023 into 2025.
Mack ran support with CTO Mark Widman across 3,127 tickets, joining live calls to troubleshoot and collect feedback, then carrying that into a fix and a release. He was also the sole account manager for early team adopters, from small companies through a publicly traded one, running demos with the CEO, COO, CISO, or CTO, setting team configs, and taking them into MCP and custom API workflows.
Built working relationships with vendors across infrastructure, models and the rest of the stack, and kept them running day to day so product and operations had what they needed.
Supported Tsavo Knott across every round. Decks, narrative, and the numbers behind them. Then the legal work with counsel for the Seed, the Series A and the bridges between, through SAFEs and convertible notes. He also handled equity and cap-table administration, and payroll and benefits.
Worked with Knott on company vision and strategy, and was the main product designer on nearly every product surface. He also worked with designers on brand and identity, with writers on documentation, and with the team on events, conferences, and collateral. A lot of the week went to content, documentation, SEO, the website and landing pages, and the specs underneath them. When the company had a gap, he was usually the one who filled it.
Part of that ran in public, and he took his share of it. He opened StartupCincy week in 2022 with a note to a full room, sat on a panel at MidwestCon in 2024, and showed the company at Civo Navigate in Austin. Pieces appeared on a slide in Satya Nadella's Microsoft Build keynote in 2023, one logo in a grid of them.
State and federal filings and R&D tax credits ran with the company's accounting firm. He took Pieces through SOC 2 Type II, opening up the buyers who required it.
Team dinners, conferences, speaking engagements and panels.