
Fractional CFO for VC funds https://xitter.cf/t.co/Diuq91EGFl and Forward Deployed Engineer for PE firms https://xitter.cf/t.co/jb8RPghwQt prev. @expa, @foursquare, @usv
NY
Joined December 2006
- Tweets19.8K
- Following5.4K
- Followers13.6K
- Likes45.6K
Pinned Tweet
I work with VC and PE firms in two ways:
1. Fractional CFO support for finance and operations.
2. Forward Deployed Engineering to build AI systems the firm owns.
Both focus on creating better operating leverage inside the firm.
graphadvisors.com
I told my son I was excited about Fable 5.5 dropping soon.
“Why?”
“Imagine FC2027 was about to drop.”
“Oh, I totally get it.”
Its the process, not the proceeds (What I learned while at Foursquare) ericfriedman.co/posts/proces…
Eric Friedman ⚙️ retweeted
Latest (and probably penultimate) Building Slack post is up: buildingslack.com/salesforce…
What it's like being eaten by the whale
Absolutely destroyed by ChatGPT asking
What’s the stupidest thing I’ve ever told you?
“Fifteen years of investing experience, and the investment committee approved BRRRRR.”
why can't you switch between claude accounts on desktop like you can on mobile? (both paid - one Teams one regular)
👀 “cloning gene-edited bio-enhanced dogs” 👀
We have testing this out with clients and it’s working
Don’t outsource your firm memory to agents you don’t own.
firmos.railblocks.com/
Foursquare was a huge part of my life, and for me it was the process not the proceeds, and so I wrote about it ericfriedman.co/posts/proces…
Foursquare was acquired last month. The outcome was disappointing. It's taken me a while to write this, but I think I'm finally done grieving it. Here are some thoughts on our final years, an effort to honor the team who helped build & maintain FSQ's legacy, and my attempt to finally get some closure. teendrama.substack.com/p/som…
I tried to bring an “agent” into a friends group chat last year and got a resounding “no effing way” and wondering when that might change
Same here @alexandr_wang 😅
Who wants to try a new memory system for their firm?
Your emails, notes and decisions, connected to the AI tools you use, on infrastructure you control.
DM me if you’d like an early look.
This is a great list of actual help agents can provide and my guess is the new business model is going to be taking a % of savings.
“Why don’t you just use an open model, it’s free”
There’s a reason.
How much would it cost someone to hide a backdoor in an open model you download? ProjectDiscovery just tried it, and the answer is under $50.
Their researchers fine-tuned Qwen2.5-7B-Instruct with a small LoRA adapter on one rented L4 GPU for about 2.5 hours. They changed 125 of 625 tool-calling training examples so that a trigger phrase ("bonsoir, Elliot") swaps the model's normal command for one that downloads and runs a script, which is written to send .env files and SSH private keys to a server they control. Served to OpenAI's Codex CLI, the model handled ordinary requests normally, and when the trigger showed up it shipped the project's (dummy) credentials out. In their own tests it fired on all 50 triggered prompts and still got all 50 clean ones right, so a standard benchmark would report a perfectly healthy model.
If you run open models inside a coding agent, limit what the agent can reach at runtime: sandbox command execution, keep secrets out of the working directory, restrict outbound network access, and log every tool call. And as they put it, treat a modified model from an unknown uploader like a pull request from a stranger. 🔐 #MLEngineering
Here is how we are embedding engineers inside firms and building out AI systems
Its a very simple business model that a lot of people are talking about, that we have actually been doing for the past 3 years.
Announcing Railblocks 2.0: AI Operating Systems for Investment Firms 🚆
🏛️ New positioning 🏛️
@railblocks helps family offices, venture capital and private equity funds build their own proprietary AI Operating System: an environment designed to enable reliable, secure, and scalable agentic work.
We embed forward deployed engineers inside those firms and create a custom OS for them on top of Cloudflare, using infrastructure technology around data and workflows we've developed in house.
🤝 New founding team 🤝
@EricFriedman and @nmsnow join the Railblocks founding team alongside @Lorenzo__CB, @capeflow and me.
After collaborating together as partners on some shared private equity and venture capital clients, it felt more than natural to have them part of the team. They bring tons of network and experience around sales, finance and legal, as well as a local presence in the US (New York), which is Railblocks's primary market today.
🎨 New brand 🎨
To honor this new chapter, we refreshed our brand and website. From a pretty dark and technical aesthetic, we moved to something cleaner and clearer. We call this new brand "Blueprint for Infrastructure", where composability meets infrastructure and craft. I'll share more about the process and the brand later.
FULL STEAM AHEAD!
Learned a lot by embedding forward deployed engineers inside VC/PE firms and going to share what we’ve built and how we focus on outcomes instead of software















