David Bielenberg

Copy, Transform, Combine
Co-Founder @permanent

Helped build @V7Labs @Pipe @Harmonic_AI @ListenLabs @withdefault @peec_ai and many more

[Sherwood @shcallaway]

We raised $8m to build self-healing software.

In 2026, software moves fast.

But monitoring and observability are still manual and slow.

@sazabi is a next-generation observability platform for fast-moving engineering teams.

Not another AI SRE.

Not another LLM observability tool.

A new, general solution to observability that works for any workload (including agents) and leverages AI for maximum speed and automation.

Time to suit up.

[David Bielenberg @DavidBielenberg]

For the past months @permanent partnered with @sazabi to build AI-native monitoring & observability. They just closed their seed round with this gorgeously on-brand launch film. Absolute cinema.

[Sherwood @shcallaway]

We raised $8m to build self-healing software.

In 2026, software moves fast.

But monitoring and observability are still manual and slow.

@sazabi is a next-generation observability platform for fast-moving engineering teams.

Not another AI SRE.

Not another LLM observability tool.

A new, general solution to observability that works for any workload (including agents) and leverages AI for maximum speed and automation.

Time to suit up.

[David Bielenberg @DavidBielenberg]

@niclasernst Shoutout to me for sticking it to the wall with 3M Tape!

[Y Combinator @ycombinator]

Sazabi is a next-generation observability platform designed for fast-moving, AI-native engineering teams.

If you're using Datadog, Sentry, Grafana, or Axiom today, you could be moving ten times faster with @sazabi.

Congrats on the launch, @shcallaway!

https://t.co/dpjfxXDxkR

[Sazabi @sazabi]

We're live on Launch YC! 💫

[niclas @niclasernst]

Lots to come @permanent

[albert @albertzimtea]

built with taste

web & product by @permanent

[niclas @niclasernst]

It’s been fantastic working with @nicoaferr and team on Default through every fiber of the company. Happy with where we ended up here.

[David Bielenberg @DavidBielenberg]

For the past months, we've been collaborating with @withdefault to help shape the context engine for go-to-market teams. Congrats on the $20M funding round announced yesterday!

[nico @nicoaferr]

Today, I'm incredibly excited to announce @withdefault's Series A led by @8vc and our new product.

We spent the last three years building the tools and orchestration layer companies like @owner and @AirbyteHQ have used to build infrastructure across their go-to-market functions.

Today, we're launching the first real-time data layer for go-to-market, a powerful new revenue agent, and a suite of tools for revenue teams and their agents.

It's Day 1.

[Antoine Plu @AntoinePlu]

What a great collaboration between @withdefault and @permanent at every levels 🔥

Special kudos to @DavidBielenberg, @albertzimtea and @bollmann0x for the work done with care across the board. The new website that comes with the announcement is on point: https://t.co/5y53aNmVSi

[nico @nicoaferr]

Today, I'm incredibly excited to announce @withdefault's Series A led by @8vc and our new product.

We spent the last three years building the tools and orchestration layer companies like @owner and @AirbyteHQ have used to build infrastructure across their go-to-market functions.

Today, we're launching the first real-time data layer for go-to-market, a powerful new revenue agent, and a suite of tools for revenue teams and their agents.

It's Day 1.

[Cormac @cormachayden_]

peak founder life is renting a remote villa and flying out your team to work for a week

[niclas @niclasernst]

Recent team retreat situation @permanent

[Jakub Antalik @Jakubantalik]

Everything from https://t.co/d7VPDcOJK0 is now available also as a skill

npx skills add jakubantalik/transitions-dev

[Sazabi @sazabi]

Sazabi is joining @ycombinator!

Y Combinator is the world's top startup accelerator and the perfect launch pad for Sazabi.

The YC community, consisting of thousands of companies, founders, and builders, represents the largest concentration of prospective Sazabi customers anywhere in the world.

Sazabi is proud to enroll in Y Combinator's P26 batch, due to start Monday, March 30th.

See you on Demo Day!

🔗 Read more: https://t.co/Lc4K6TcUGP

[Sherwood @shcallaway]

I'm returning to YC!

@ycombinator has been dream since I was 18.

I grew up in North Carolina as the son of a doctor. As a kid, I knew nothing about the world of tech or startups. California was something that only existed in movies and punk songs.

But in 2014, everything changed for me.

I spent the summer at Dev Bootcamp, a San Francisco-based web development bootcamp. That's when I first learned about YC.

Dev Bootcamp changed the trajectory of my life for the better. I finally found something I was good at - and something I was truly passionate about. Everyone at "DBC" was obsessed with Y Combinator, Hacker News, and YC startups like Gusto and Instacart. For years afterwards, it was my dream to found my own YC-backed startup.

In 2021, that dream came true - but not in the way I hoped. My roommate Justin Ko and I were admitted to YC S21 to build Opkit, a healthcare voice AI company. S21 was great, but it wasn't the full YC experience: due to the COVID-19 pandemic, the batch was fully remote.

When I set out to build @sazabi, the AI-native observability platform for fast-moving engineering teams, I never considered going back to YC.

But I reconsidered after having a conversation with @aaron_epstein, my friend and one of Opkit's partners from the S21 batch. Aaron helped convince me that YC was the best way to accelerate Sazabi's growth - and it didn't hurt that I would finally get the YC experience I had wanted for so long!

Today, I'm proud to announce that Sazabi is joining the YC P26 batch, due to start on March 30th.

We're excited to meet our batchmates, learn from them, and hopefully give back to this community that I love so much.

See you on Demo Day!

[Sazabi @sazabi]

Time's up.

The new Sazabi website, codenamed "Midnight", is live now.

🔗 Don’t miss it: https://t.co/e0BxLjwOMk

[David Bielenberg @DavidBielenberg]

So many exciting details on this site! 🦾

[Sherwood @shcallaway]

It's here.

Today we’re unveiling the new @sazabi marketing site, codenamed "Midnight". 🌃

The Sazabi team pulled ZERO creative punches on this project and the results speak for themselves.

Trust me. You’ve never seen ANYTHING like this before. ❤️‍🔥

Since coming out of stealth ~1 month ago, everyone’s been asking to learn more about Sazabi. Our original “splash page” was designed to generate intrigue, not serve as FAQ or product explainer.

But the time for vagueposting is over!!!

Midnight pulls back the curtain on what Sazabi has been building for the past few months: the AI-native observability platform for fast-moving engineering teams.

I'll warn you, the site is strange. But that's by design.

Sazabi is doing things differently. This isn't your dad's observability platform.

Check it out now: https://t.co/nUxOJ5SXSu

[David Bielenberg @DavidBielenberg]

RT @shcallaway: It's here.

Today we’re unveiling the new @sazabi marketing site, codenamed "Midnight". 🌃

The Sazabi team pulled ZERO crea…

[Din Bisevac @DinBisevac]

Buena is expanding into banking.

Reimagining how properties, homeowners & tenants bank in the future.

If you want to shape this future and then roll it out to our 70.000+ customers, DM me.