Microplastic Filtration, Factory Economics 101 from a16z, and 3 Lessons from 30 Years

Happy Thursday.

In today’s issue:

• Angel Deals of the Week | 149 Deals, 96 Networks

• Bookmarks I think you’ll enjoy

• The Nugget: 3 Reflections from turning 30

🔥 Angel Deals of the Week

Angel funding rounds announced in recent weeks, compiled from public sources or via direct announcement. These deals represent the elite few that survived an angel network’s vetting process. Note: I have not personally analyzed these companies and am sharing for informational purposes only.

📊 Angel Network Investment Tracker: 149 Deals, 96 Networks.

GelMEDIX | Hydrogel scaffold for retinal cell therapy

Participating Groups: Beacon Angels, Boston Harbor Angels, TiE Boston Angels

GelMEDIX is developing an injectable hydrogel scaffold platform designed to improve the delivery and integration of cell and gene therapies, with a lead program targeting Geographic Atrophy (GA), a progressive form of dry age-related macular degeneration that causes irreversible central vision loss. The company recently closed a $13 million seed round led by Safar Partners, with participation from HTL Biotechnology, Beacon Angels, Boston Harbor Angels, and TiE Boston Angels. Proceeds will advance GMX-101, an RPE cell therapy, and support a newly announced partnership with an undisclosed global pharmaceutical company.

Max Cotler | $13M Seed | Cambridge, MA | February 2026 | Source

Hardshell | AI training data security platform

Participating Group: CAV Angels

Hardshell is developing a platform that secures sensitive datasets used to train AI models, addressing threats such as data poisoning, leakage, and integrity risks before they reach models - rather than monitoring outputs after deployment. Founded in 2025 by a DOD AI expert and U.S. Army cyber veteran, the company targets healthcare, defense, and other regulated industries. Hardshell recently raised $1.1M in pre-seed funding from CAV Angels, VTC Ventures, Front Porch Venture Partners, Blu Ventures, MoJo Ventures, Not Yet Ventures, Black Prism Capital Partners, and other individual angels.

Andrew Schoka | $1.1M Pre-Seed | Charlottesville, VA | February 2026 | Source

PolyGone Systems | Microplastic water filtration system

Participating Group: Golden Seeds

PolyGone Systems, a Princeton University spinout founded in 2021, is developing a patented filtration system that the company says removes 98% of microplastics from water at 90% lower cost than alternative methods. The company operates a pilot with the Atlantic County Utilities Authority and reports three new commercial deployments signed in 2026. It recently raised $4 million in Seed funding from FYRFLY Venture Partners, Golden Seeds, and others, including NJ Innovation Evergreen Fund matching, to deploy municipal and industrial filtration systems.

Nathaniel Banks | $4M Seed | Kearny, NJ | February 2026 | Source

📣 Have an Angel Deal to Announce?

🎙️Join Me at the ACA Summit in Denver

The ACA Summit is back in Colorado this April, and The Diligent Observer will be there. We're recording conversations with leaders from some of the most active angel groups in the country. If you're in the room, come find us!

This is my favorite event every year. It’s the one place where angel group leaders, individual investors, and ecosystem builders are all under the same roof for three days: April 21-23 at The Westin in Westminster, CO. Keynotes from Peter Walker and Angel Gambino, five breakout tracks, Angel University courses, a giant startup showcase, AND a fun poker tournament.

Don’t miss it.

🎟️ Not an ACA member? Register with code “DO200” and save $200. Early-bird pricing ends tomorrow, so sign up before prices jump.

Register for the ACA Summit →

P.S. Missed last year? Check out “Inside Angel Investing 2025: The ACA Summit”.

🔖 Bookmarks

1. 🏭 Factory Economics 101: Comprehensive primer from Oliver Hsu at a16z on why mastering yield, learning curves, and capital structure is essential for "factory-is-the-product" startups. Great read.

2. 📊 The State of Pre-Seed, By the Numbers: Research from Carta breaks down $10.4B raised across 50,316 SAFEs and convertible notes in 2025 - fewer overall deals, but total cash invested mostly flat.

3. 🚀 The Space Economy Playbook: NFX makes the case that space is following the same cost-collapse pattern that gave us global trade, suburbs, and Sears catalogs.

🥇 The Nugget: Reflections on Turning 30

This week, I celebrated my 30th birthday. I spent 8 of those years as a husband, 5 active in the startup space, 3 as a full-time founder, 2 as a dad, and every single one of them as a deeply flawed yet deeply grateful person.

Naturally, I’m taking stock of - well, everything - so I wanted to pause this week and share 3 beliefs I've formed over the years.

1. Life is kettle vapor. → Most valuable resource: time and relationships.
   This morning, like every other morning, I boiled water to make coffee. The “kettle vapor” spewing from the top is exactly what life is like. It disappears into nothing so fast, and there’s nothing I can do to grasp it. And so, I’ve come to believe every moment in life is a gift, and the most valuable resources afforded to each of us are our time and the people we get to spend life with.

2. Conviction is exceedingly rare. → Be brave.
   In our modern world of overwhelming choice, it’s so, so easy to “float along” in life and live “on the fringes” without ever fully committing to something - to keep scrolling instead of making a call. Making a call is terrifying. Marriage. Career. Health. The temptation presents itself in every area of life. And I’ve noticed those who live in bold rejection of the status quo - who live with bravery and deep conviction - tend to inspire and rally others around them like magic. I aspire to become this kind of person, and hope you will too. 

3. The world is clay, not concrete. → Don’t artificially limit what’s possible. 

   When I was 20, the world felt like concrete. Rules were well-defined, everyone seemed to know what they were doing, and I was just trying to find somewhere to fit in. So I only saw a limited number of options. At 30, I’ve realized it's far more like clay. Every system, every institution, every "rule" I spent my twenties tiptoeing around has a human fingerprint on it. Someone, somewhere, just... made it up. And that means someone else can reshape it. So ask the question. Try the thing. Sure, maybe it fails. But maybe it doesn’t - the clay is softer than it looks.

See you at 40.

🕵️ Looking for an Angel Group?

Finding the right angel community can be tough.

Answer 12 quick questions and I’ll curate 3 groups you might enjoy.

Even better - if one of them feels like a fit, I’ll personally make the intro.

Until Next Week 👋

Thanks for reading - have a great week.

-Andrew

P.S. If you enjoyed this post, could you do me a quick favor? Hit the "like" button or leave a comment with your thoughts. It may not seem like much, but it really helps me out a ton.

If you’re finding this newsletter valuable, share it with a friend, and consider subscribing if you haven’t already. You can also find me on LinkedIn and X.

Advertise with The Diligent Observer.