Michael Rumiantsau

Founder, Investor, Product Leader

[Michael Rumiantsau @MicRum]

Published a new study/benchmark on how semantic layers make LLM analytics reliable.

A simple 4 KB markdown file in the prompt improved accuracy by 17-23 percentage points across every model

https://t.co/vtSuVSZjH9

[Michael Rumiantsau @MicRum]

Speaking at the Agentic Analytics Summit tomorrow on how semantic layers make LLM analytics reliable.

Releasing the research, the benchmark, and the dataset: all open.

https://t.co/fuUS8zurGf

[Michael Rumiantsau @MicRum]

me: what's my deep research limit?
openai: we won't tell you, but it will be reset on Friday
me: (waited until Saturday) okay, which Friday?
openai: we won't tell you
me: canceled ChatGPT Plus, subscribed to Claude Pro

[Michael Rumiantsau @MicRum]

@p_fabrikantov Their software is great too! Restored everything in minutes using their sample tool

[Michael Rumiantsau @MicRum]

When you realize format and factory reset are not the same thing..

[Michael Rumiantsau @MicRum]

It's interesting how big tech is being pushed toward headless architectures, while large LLM providers are eating the software market with specialized tools like this.

[Claude @claudeai]

Introducing Claude Design by Anthropic Labs: make prototypes, slides, and one-pagers by talking to Claude.

Powered by Claude Opus 4.7, our most capable vision model. Available in research preview on the Pro, Max, Team, and Enterprise plans, rolling out throughout the day.

[Michael Rumiantsau @MicRum]

https://t.co/htKhlaRihs

[Michael Rumiantsau @MicRum]

@dieworkwear https://t.co/BckRzDm81x

[Michael Rumiantsau @MicRum]

Any time of the year in SF: one person in shorts and tee, another in a winter coat.

[Michael Rumiantsau @MicRum]

I think I spend more time organizing things than I save by having them organized 🤔

[Michael Rumiantsau @MicRum]

Me watching ChatGPT (Agent Mode) trying to type a date into a date picker control

[Michael Rumiantsau @MicRum]

One year later, that day finally came!

AI logs startup pitches into a spreadsheet, pulls the decks, and writes short analyst-style reviews.

Workspace Studio works like a charm! Native in Gmail, no Mac mini needed.

Now I’m just hoping Google doesn’t randomly kill it.

[Michael Rumiantsau @MicRum]

Looking at my inbox with 1400+ unread emails… Probably going to wait for the next AI model to handle it. Closing browser.

[Michael Rumiantsau @MicRum]

This is the "Cursor" moment for data analytics

[Artem Keydunov @keydunov]

Introducing Cube.

The first platform where AI builds your data model for you.

Get accurate answers, dashboards and reports automatically.

No hallucinations. All grounded in the semantic layer.

Cube is free to start at https://t.co/iOJt1kFZAd

[Michael Rumiantsau @MicRum]

@MaksimAbramchuk I don't care about nudes, it's their private business. But the screenshots I attached read like human trafficking and possible Russia-linked spying.

[Michael Rumiantsau @MicRum]

Just a few examples from the recent DOJ release. Decide for yourself.

[Masha Bucher @mashadrokova]

Growing up in post-Soviet Russia, I joined the regime's youth movement at 15, believing it was the path forward. By my late teens, I saw Putin's corruption and evil up close. I left, spoke out (including in the documentary *Putin's Kiss*), and defected to the US.

After receiving my green card in 2017, Russian state media branded me a traitor.  My family faced real consequences - my father lost his job - and we lived under constant threats and scrutiny from the Russian government. Dissidents abroad were (and still are) targeted, and the danger has only worsened. I was terrified and desperate for safety and stability.

In this context I first connected with Jeffrey Epstein in 2017. It was two months after the huge attack in Russia on me and my family. He made me feel I could be safe from the regime, someone with power and connections who could shield me from those threats. I was naive; I didn't dig deep enough early on. In fact, I didn't even know such a person existed before our first meeting. I believed his story that his earlier conviction was about sleeping with a girl who lied about her age and trusted validations from multiple investors and scientists. I regret that deeply.

I made four introductions to journalists over two years (unpaid, as documented) and never visited his island. I leaned on his reassurances and trusted those around him. I now see clearly how profoundly dark and evil he was - a master manipulator who preyed on vulnerability with chilling precision. I have since connected with some of his victims and learned a similar pattern of taking in women who felt they had nowhere else to go, making them feel safe, and then threatening to take away that safety in exchange for submitting to his demands.

To my founders, team, and investors: I'm truly sorry. This has caused pain I never intended.

I gave up my Russian passport years ago, can't return without risking my freedom, and have publicly opposed the Putin regime. I haven't seen my elderly grandparents in five years - this was the price I paid to do my work here and serve the purpose building the most important companies of our time. After Epstein died, I supported the investigation and assumed that from then and forever whatever I do will be under the microscope for regulators. I’m definitely the most closely watched VC out of all on all the cap tables of our portfolio companies.

Fuck Putin. Fuck Epstein.

I love America, the values it stands for, and the incredible people building the future here. Day One Ventures and my founders are my life. I'll keep fighting for them and for what's right.

[Michael Rumiantsau @MicRum]

@__flatlined I think she blocked me

[Michael Rumiantsau @MicRum]

@gokulr @OpenAI eg the semantic layer

[Michael Rumiantsau @MicRum]

@gokulr @OpenAI eg the semantic layer

[Michael Rumiantsau @MicRum]

It's time to start labeling non ai generated content "certified organic" or something

[Michael Rumiantsau @MicRum]

@atsohom1 More thoughts on this

https://t.co/mLG9i2dJJT

[Michael Rumiantsau @MicRum]

Some founders start companies not out of ambition, but guilt. Leadership becomes a way to avoid own needs, overfunctioning for others.

[Michael Rumiantsau @MicRum]

full essay: https://t.co/mLG9i2dJJT

[Michael Rumiantsau @MicRum]

On not giving up