Adam Marcus

@marcua.net

2895 Followers 236 Following

Hummus, people, and data. Co-Founder & CTO of B12. Previously Locu, MIT CSAIL. He/him. https://marcua.net/ Queens is the future.

A sign that says vote here/vote aqui
How to use Figmimic: install the bookmarklet, click the bookmarklet to copy any page, and paste the copied result into Figma.
A timeline of the professional experiences a junior engineer used to develop over several years. Skills that used to take years to hone are now required in your first moments with a coding agent.
A photo outside a black building labeled "The Punk Rock Museum" in neon green, with a hat that says "SKA" at the bottom of the photo
A snippet from the introduction to the blog post: Four questions agents can't answer Software engineering after agents write the code Feb 25, 2026 You’ve likely read countless words about how coding agents have massively changed software engineering. At the extreme, December 2025 was the turning point and we’re unlikely to write a line of code again. But amidst all this talk of change, it helps to understand what likely won’t. I’m particularly interested in the questions agents can’t answer, doubly so if they are unlikely to answer them well in the coming years. Here are four such questions that blur the line between product management and software engineering. The questions reflect the fact that as coding agents cover more of the nitty-gritty of code generation, humans will be responsible for higher-level concerns. I think these questions will remain in the human domain for years to come: What should we work on? How much of it are we doing? How do we do it well? What’s getting in our way? These questions are durable: we’ve encountered them since software engineering became a profession, and we’ll be responsible for them as long as we’re responsible for the products and systems we share with the world. The answers to these questions require judgment based on goals and constraints that are organization-specific, dynamic, and don’t live in some task management or issue tracking system you can integrate with. It’s hard to imagine an agent successfully synthesizing these disparate and context-specific inputs into answers. What should we work on? Companies tend to work at the intersection of what their users find valuable, what the business finds
A video showing someone installing a bookmarklet in their browser, navigating to a GitHub pull request, clicking the bookmarklet, seeing the comments on the request in a modal in markdown format, and copy/pasting those comments after some edits into Claude Code.
A screenshot of the "Reflections and takeaways" section at the end of https://data-people-group.github.io/blogs/2025/09/30/ten-papers/.
A video walkthrough of the new ayb web interface
A screenshot of a page of an electronic book, with this relevant quote: "In the last year in researching this book, I could not travel and I carried oxygen tanks in order to breathe. In July 2010, I received a double lung transplant, and following two months' hospitalization, managed a full recovery."
A screenshot of Google results that highlight the wrestling coach (not other notable people) of Wantagh, NY.
An animated GIF of a user uploading a CSV with three countries in it and adding population and capital columns that are automatically added to the newly downloaded CSV.
A screenshot of an email. Subject: [marcua/ayb] Notification (Issue #XYZ) Content: Security Alert: Unusual Access Attempt We have detected a login attempt on your GitHub account that appears to be from a new location or device. Login Information Location: Reykjavik, Iceland IP Address: 53.253.117.8 Device: Unrecognized If you recognize this activity, no further action is required. However, if this was not you, we strongly recommend securing your account immediately. Steps to Secure Your Account Update your password to prevent unauthorized access: Change Password Review and manage active sessions: Check Recent Activity Enable Two-Factor Authentication (2FA) for additional protection: Set Up 2FA Contact Support If you need assistance or suspect a security breach, visit: GitHub Security Support Thank you for keeping your account secure. GitHub Security Team — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you are subscribed to this thread.
A git diff summary, with +73,581 lines added and -57,165 lines removed
A screenshot of the following text: I'm supposed to be writing in a stream of consciousness manner without self-editing, as this writing is just for my personal journal. That said, I started to think that what I'm writing above could turn into a blog post for public consumption and caught myself editing it, moving text around, preceding text with caveats, and freezing as I think about all of the holes people will make in this argument. That's not at all the point of this journal, so to unfreeze myself, I wrote this paragraph to get it out of my mind :).
The album cover for "Love Everybody" by The Presidents of the United States of America, in which a baby is holding up a sign that says "Love Everybody"
A hand-drawn cartoon diagram in which both the user and the application have a database. The user authenticates their database to the application, which tracks that database in its own database. The application's database acknowledges the insertion to the application, which acknowledges the insertion to the user.
A hand-drawn cartoon diagram in which a user provides data to an application, which inserts it into a database. The database acknowledges the insertion to the application, which acknowledges the insertion to the user.
A two-part diagram. In part 1, a user gives their data to a server, which stores it in a database. In part 2, the user requests their data, and the server responds “nope.”
A graph in a sawtooth pattern that progressively grows taller and has steep drops that don't reach their previous lows
A mobile phone notification that reads “New follower! Elon Musk has followed you now”
Two headlines 1. Officials from the NYPD and MTA said they're launching a fare enforcement crackdown today on bus routes deemed to be "egregious" hot spots for fare evasion. 2. Manhattan Borough President Mark Levine is urging TikTok, Facebook and Craigslist to get rid of black markets selling "ghost plates" that drivers use to evade tolls.
A screenshot of a GitHub pull request The branch name is no-i-dont-want-your-domain The lyrics quoted at the top of the description are: No, I don't want your number No, I don't wanna give you mine and No, I don't wanna meet you nowhere No, don't want none of your time - Chilli from TLC
A screenshot of the documentation at https://github.com/marcua/ayb#running-a-client