Jens Eickmeyer

Solving business challenges with lean software solutions | Head of Software Engineering @PaiconAI | Slow is smooth and smooth is fast

[Jens Eickmeyer @jenseickmeyer]

It took me a while to figure out how to debug Rails applications and RSpec tests in VS Code. Finally got it working using the great Ruby LSP extension.

I summarized the steps in a blog post 👇🏻

[Movez @0xMovez]

Spotify's Chief Architect just showed how they ship 4,5K deployments /day with Claude at Anthropic stage

27-minutes. free. By #1 music app dev

"More than 99% of our engineers use AI coding tools. Adoption took off after Opus 4.5"

Worth more than any $500 vibe-coding course.

[Jens Eickmeyer @jenseickmeyer]

@VolkerPetzer Das war auch mein erster Gedanke.

[Jens Eickmeyer @jenseickmeyer]

@peetersn @OmarchyLinux @dhh I had the same experience a couple of month ago. Am using it daily on my 2012 iMac now.

[DHH @dhh]

Convention over configuration set the path for 20+ years of great training data for AI to use today. Not only does this mean agents do great with Rails, but also that squishy humans can quickly and confidently review the output without a jungle of distracting boilerplate.

[Jens Eickmeyer @jenseickmeyer]

@lucianghinda Just ping me if you have any more questions. I'd be happy to help out.

[Jens Eickmeyer @jenseickmeyer]

@tobi What tools and models are you using? @opencode? Claude Opus 4.5?

[Jens Eickmeyer @jenseickmeyer]

@strzibnyj What do you mean by that?

[Jens Eickmeyer @jenseickmeyer]

@peetersn @AnthropicAI Thanks for sharing! Will watch it later.

[Jens Eickmeyer @jenseickmeyer]

@marcoroth_ Well deserved! Thanks for your amazing work!

[Jens Eickmeyer @jenseickmeyer]

@robinalexander_ @rosidaggi Viel Erfolg! Freue mich auf viele weitere spannende Folgen in 2026 mit interessanten Blicken hinter die Kulissen des politischen Geschehens.

[Jens Eickmeyer @jenseickmeyer]

@TweetsOfSumit Man kann es auch positiv sehen: Du hast es geschafft deinen Traum zu leben und ein Unternehmen aufgebaut, welches Umsätze und vor allem Gewinne erwirtschaftet.

Trotzdem wünscht man sich natürlich niedrigere Abgaben.

[Peter Clack @PeterDClack]

They told us China was cheating. Turns out they were just building while we were preaching. While the West was busy dismantling coal plants, paying people not to boil kettles and covering farmland with solar panels that don’t work when it’s dark, China did the obvious: They kept the lights on and built everything.

The result? China now makes 80% of the world’s solar panels, 70% of the batteries, 60% of the wind turbine parts and 55% of global steel (more than the next 15 countries combined). And they’re still commissioning two state-of-the-art coal plants a week – the cleanest coal plants ever built, because reliable power beats ideology every single time.

In 2000 China’s manufacturing output was smaller than Italy’s. Today it’s larger than America + Europe + Japan + South Korea combined. We outsourced the actual hardware of the 'green revolution' to our main rival, then acted surprised when they became the workshop of the world and the richest industrial power in history.

The miracle isn’t mysterious. It’s embarrassingly simple:
Abundant energy. No net-zero cults. A government that sees steel mills and giga-factories as strategic assets, not sins. The biggest transfer of wealth and power in human history didn’t happen with guns or treaties. It happened because one side built things and the other side wrote strongly worded letters and paid influencers to shame anyone who pointed it out.

China installed more solar in 2024 than the entire world had installed cumulatively by 2017.

From 2005–2023 China added ~1,100 GW of coal capacity while the West lost ~200 GW. That gap is the story of the century.

The West ran a 20-year experiment in whether you can deindustrialize your own civilization, hand the manufacturing base to a strategic rival, subsidise that rival with your own climate policies, yet still win the century.

Result so far: China’s manufacturing share of global GDP went from ~6% in 2000 to ~30% today. America’s went from ~22% to ~15%. Europe’s collapsed from ~25% to ~14%.

China didn’t beat us. We decommissioned ourselves.
Ready to discuss?

[Jens Eickmeyer @jenseickmeyer]

@TweetsOfSumit @Cloudflare Again?!

[Jens Eickmeyer @jenseickmeyer]

@TweetsOfSumit I agree with you. On paper and from a technology point of view, Serverless is great. But in reality it has all kinds of flaws and drawbacks.

After using Microservices and Serverless architectures I'm back to the good old Monolith. And I love it!

[Jens Eickmeyer @jenseickmeyer]

@arvidkahl I totally agree with your point of view.

in my opinion, the release of Fizzy as open source is a invaluable gift, especially to the Rails community. It is great to see how the creators of Rails are using the capabilities of the framework to build great products.

[Jens Eickmeyer @jenseickmeyer]

@E_Boeminghaus Das ist eine sehr berechtigte Frage.

[Jens Eickmeyer @jenseickmeyer]

@E_Boeminghaus Die Einschläge kommen näher...

[Jason Fried @jasonfried]

People have been asking what happens to ONCE now that Fizzy is both SaaS and Open Source? Are we going to make any more ONCE products?

First some quick background.

In September of 2023 we announced ONCE.

ONCE was the reintroduction of an old idea. Rather than subscribe to software in perpetuity, you could just pay for it once and own it rather than rent it. It came with all the code too, so you could run it yourself and modify it for your own use.

We launched two products under the ONCE umbrella. Campfire, a group chat tool. And Writebook, an online book publishing tool. Campfire was $399 (once), and Writebook was completely free (forever). Just recently we made Campfire free, too. Today both are available as open source under the MIT license. (Repo links)

So now that both products are free and open source, what does that mean for ONCE itself?

While we didn’t know it at the time, we’ve since discovered that ONCE was more a direction than a destination. And now that we know where we’re headed, we’ve decided to wind down the ONCE model, and wind up something better: A new model combining the best of SaaS and Open Source. You can pay us to host and support the software for you, or you can run and modify it yourself for free.

Companies like Wordpress, Ghost, Plausible, and Gitlab offer software under this model already. We’re proud to join these pioneers. We think this is the right way forward.

Fizzy is the first product we’ll be releasing under this model at 37signals.

Practically, this means Fizzy will be available two ways right from the get go:

1. Traditional SaaS. Sold by us, hosted by us, supported by us. Free option + paid plan.
2. Open Source. Entirely free, hosted by you. Change it to fit you better, fork it, or, even better, collaborate with us, submit PRs, and improve it for everyone.

A 1-2 punch, the best of both worlds.

As a company, we’ve been building SaaS software for more than two decades. Basecamp, Backpack, Highrise, Campfire, HEY, and others. We were among the early pioneers in SaaS, so we know it intimately.

We’ve also been making open source software for more than two decades. From Rails to Hotwire to Kamal to Trix to Omarchy to a couple hundred other repos, we’re soaked in open source. We’re built on it.

But we’ve never married the two. We’ve never offered a commercial SaaS product as open source as well. Fizzy, a fresh take on kanban, is our first.

We’ve put an enormous about of effort getting Fizzy 1.0 right while purposefully leaving it wide open to all sorts of potential features, futures, and integrations. So we’re inviting the community to help us build Fizzy into an absolute powerhouse of a platform.

And with that, we invite you to check out Fizzy at https://t.co/pGxSDeGcYc.

It’s a new era. Let’s go!

[Jens Eickmeyer @jenseickmeyer]

@jasonfried BTW: I really like the logo!