German Velasco

8 Sept

Who's going to @elixirconf.bsky.social in a couple of days? I'd love to meet up! #ElixirLang

andrealeopardi.comElixir's GenStage Demand (a Visual Explainer)Concurrency gives us more workers; demand tells us when to stop sending them work. This is what I want to point people to when we talk about "demand".

This blog post by @whatyouhi.de is amazing. The best explanation of GenStage I've seen. andrealeopardi.com/posts/gensta... #ElixirLang

I think the reason for that is that `min_demand` is not a true counterpart to `max_demand`. (`max_demand` makes sense to me) But GenStage's docs explain it correctly: ":min_demand specifies the minimum threshold to trigger for more demand"

So, I think if we renamed `min_demand` -> `min_threshold` or `resupply_threshold` it would remove the confusion that max & min demand bring. And that would help people understand GenStage more easily. #ElixirLang

This blog post by @whatyouhi.de is amazing. The best explanation of GenStage I've seen. andrealeopardi.com/posts/gensta... #ElixirLang

That post mentions `max_demand` and `min_demand` as "the thing that trips people up the most". I totally agree. It's what's always tripped me too. It made me think: why is that?

phoenix-test.hexdocs.pmPhoenixTest — PhoenixTest v0.12.0

5 Aug

Just published Phoenix 0.12.0! 🎉 Excited for this one because it now supports `aria-label` and `aria-labelledby` Thanks to contributors for making it happen! 🥳 phoenix-test.hexdocs.pm/PhoenixTest....

germanvelasco.comDiverge then converge with LLMsOne of the patterns I've found particularly helpful with LLMs is the diverge-then-converge pattern. LLMs excel at both of those things separately, and when we put them together, they are an excellent ...

3 Aug

I keep finding that the diverge-then-converge pattern is really helpful with LLMs. So, I wrote a post about it. Hope others find it helpful! ✍️ www.germanvelasco.com/blog/diverge...

germanvelasco.comGerman VelascoSoftware developer and consultant. Let's build great software together.

For the first time in a while, I have an opening for new clients (in September). Do you need help with your product, engineering team, or an Elixir/Phoenix project? How I help teams (3 Ps) 👇

- ♻️ Process: continuously improving how your team builds, coordinates, and delivers your product

germanvelasco.comGerman VelascoSoftware developer and consultant. Let's build great software together.

Through it all, I practice and teach a culture of continuous improvement so that, long after I'm gone, your team can continue the virtuous cycle of self-improvement. DMs are open, or email me at german(at)germanvelasco.com. And for more on how I work, see germanvelasco.com

germanvelasco.comGerman VelascoSoftware developer and consultant. Let's build great software together.

For the first time in a while, I have an opening for new clients (in September). Do you need help with your product, engineering team, or an Elixir/Phoenix project? How I help teams (3 Ps) 👇

- ✨ Product: building the best possible product for your customers. I care about the solution end-to-end.

elixirstream.devhttps://elixirstream.dev/gendiff/api# gendiff — Markdown API for coding agents Generate a diff of a project generator's output between two versions, rendered as Markdown built for LLMs. Fetch one URL, get the diff — no UI needed. ## E...

- 🧑‍💻 People: strengthening your team's technical and product skills as we improve the product (remember, your team is the engine behind your product). Mentoring, pair programming, workshops, whatever is needed to make your team the best version of itself.

German Velasco reposted

David Bernheisel

@david.bernheisel.com

24 July

Next time you're upgrading Phoenix and you're using AI assistance, try pointing it to elixirstream.dev/gendiff/api and tell me how it goes. cc @steffend.me #ElixirLang

17 July

What are companies in the #ElixirLang space struggling with right now? AI adoption? Finding product-market fit? Team dynamics? Hiring? Something else? (I know there's varied answers, but curious if there are commonalities)

germanvelasco.comAre plan files the new 10k-line PRs?Many people's new way of working with LLMs is to start with an idea, have the LLM create a spec (review and approve that), then have the LLM generate a very detailed plan. At that point, people have t...

7 July

I'm not a big fan of the big-upfront-plan approach to work with LLMs. Am I the only one? I wrote a bit about it in www.germanvelasco.com/blog/are-pla...

germanvelasco.comReflections on creating ExCrap without looking at the codeI recently published ExCrap, an Elixir library for calculating Change Risk Anti-Patterns scores -- or as they're commonly called CRAP scores. It made for a perfect experiment: creating the library wit...

25 June

I finally finished writing the blog post that shares some things I tried (some good, some bad) when creating ExCrap without reading the code. Hope others find it helpful! ✍️ www.germanvelasco.com/blog/i-wrote... #ElixirLang

German Velasco@germsvel.com

Just published a new library to calculate CRAP metrics (I know, that's what it’s called 🤷): change risk anti-patterns. It’s a metric composed of cyclomatic complexity and test coverage. 👇 ex-crap.hexdocs.pm/readme.html #ElixirLang

ex-crap.hexdocs.pmExCrap — ex_crap v0.1.0

23 June

I wrote a post for whenever you have a co-worker who wants to keep dead code around.   In particular, I love the loss aversion principle that I tried to capture in these two contrasting images in the post.

germanvelasco.comWhy dead code feels hard to deleteIt's always surprising when people don't want to delete dead code because they think they might need it in the future or because they worked so hard on it. Recently, I had one of those conversations w...

23 June

Here's the post, using the sunk cost fallacy and the loss aversion principle to analyze why people feel bad about deleting code. ✍️ www.germanvelasco.com/blog/why-dea...

German Velasco reposted

Claudio Ortolina

@claudio-ortolina.org

19 June

It was really fun! I tried to ramble as little as possible. My main point was that pi lets me build tools that are tightly integrated, and usable by me and the LLM. It helps me being more effective without relinquishing control.

German Velasco@germsvel.com

A few weeks ago, I paired with @claudio-ortolina.org where he shared a bit about his AI workflow and how he uses pi, as he walked me through his app to manage his huge (and ever growing) record collection. Thanks again Claudio for pairing! www.elixirstreams.com/ai_files/pai... #ElixirLang

elixirstreams.comElixir Streams |> Pairing with Claudio Ortolina on his AI workflowElixir and Phoenix tips, courses, and more.

elixirstreams.comElixir Streams |> Pairing with Claudio Ortolina on his AI workflowElixir and Phoenix tips, courses, and more.

19 June

ex-crap.hexdocs.pmExCrap — ex_crap v0.1.0

16 June

16 June

The other interesting part is that this was an “I won’t read the code” experiment for me. Small lib, so seemed like a good fit. I’ll write a blog post that talks more about that in detail with some lessons learned (for those interested). #ElixirLang

germanvelasco.comDraw the rest of the ___ owl (software factory edition)My guess is that most software development teams in the world are at a point where we are drawing the two circles. Those are all the teams where developers use LLMs daily. But then you hear about team...

12 June

If we want to build software factories (still an if for me), how can we build good ones? And I don’t know about you, but I think it all comes down to verification. 👇 www.germanvelasco.com/blog/draw-th...

germanvelasco.comStop writing code by hand (and feel the friction)If you're using LLMs in your day-to-day workflow, and you're only using them as assistants that you ask questions of (like a glorified Google in your terminal or IDE), or if you call on them like a ge...

9 June

Making the decision to stop writing code by hand a few months ago was the biggest small change I made that helped me see LLMs differently. It took a while, but I finally like programming with them. Wrote a post that shares some thoughts on that 👇 www.germanvelasco.com/blog/stop-wr...

youtu.bePairing with Tomasz Tomczyk on his AI WorkflowYouTube video by German Velasco

5 June

A few weeks ago, @tomasztomczyk.bsky.social was kind enough to pair with me and show me his AI workflow. It was an awesome pairing session where he showed me everything, from his new tool (crit), custom skills, commands, workflows, etc. 👇 youtu.be/9c3J4J8U6a8 #ElixirLang #AIFiles

germanvelasco.comDaily writing retrospectiveBack in April, I decided to write daily for my newsletter. Up to that point, my newsletter was mostly a delivery mechanism for my blog. But I wanted to change that. I wanted to write more.

4 June

I recently finished an experiment where I tried to write (and publish) daily, so I wrote a retrospective on it. For those interested 👇 www.germanvelasco.com/blog/daily-w...

germanvelasco.comPair-programming is a cheat codeI had that written on my office whiteboard for a while last year. I had just finished working with a client for over a year where the whole team pair-programmed full-time (we also did a lot of mobbing...

1 May

I've been writing daily in my newsletter for a couple of weeks now. Some days things just come out flowing like I've been meaning to write them for a while. This blog post was one of those (adapted from a daily post). Hope others enjoy it! ✍️ www.germanvelasco.com/blog/pair-pr...

hexdocs.pmChangelog — PhoenixTest v0.11.1

27 Apr

PhoenixTest v0.11 is out! Huge thank you to all who contributed 🥳 Changelog: hexdocs.pm/phoenix_test... #ElixirLang

germanvelasco.comGerman VelascoSoftware developer and consultant. Let's build great software together.

23 Apr

I decided to write daily (for 30 days) on my newsletter (www.germanvelasco.com#newsletter_f...) I really like writing as a tool to sharpen my thinking. So far, I've talked about sharpening our tools, stacking days, isoquants and isocots lines. If that sounds interesting, join me!

testingliveview.comTesting LiveViewTest LiveView effectively. Trust your code. Ship confidently.

22 Apr

After some deliberation, I finally decided to make www.TestingLiveView.com free! I still think it's an amazing resource, but my focus is elsewhere now. So, I wanted to make it a free resource for the community. #ElixirLang

16 Apr

Anybody interested in pairing with me (and recording) to show how you're using AI in your day-to-day for ElixirStreams? I think there's a lot of siloed information (and hints online). So, I'd love to shed some light with real people showing real usage. #ElixirLang

harkn.appEmail vs Announcements

26 Mar

Recorded a couple of tutorials to help onboarding in Harkn, and figured, why not just put them in a docs page? For those interested in Harkn, these are glimpses into how it works too 👇 👀 harkn.app/docs

Some people ask, why not just email announcements? Email is a great way to distribute them. But you're faced with the blank-cc problem. Wrote a bit more that here 👇 harkn.app/blog/email-v...

German Velasco@germsvel.com

I've been thinking (writing is thinking, right?) about why Slack, Discord, etc. are a bad fit for your team's internal announcements. It's not the right medium! More thoughts 👇 harkn.app/blog/slack-v...

harkn.appSlack vs Announcements

hexdocs.pmPhoenixTest — PhoenixTest v0.10.0

5 Mar

PhoenixTest v0.10.0 is released! It's got a lot of things, and (I think) none from me! A huge thanks for all who contributed! 🥳 hexdocs.pm/phoenix_test... 📚 Changelog: hexdocs.pm/phoenix_test... #ElixirLang

harkn.appSlack vs Announcements

26 Feb

German Velasco reposted

Lars Wikman

@lawik.bsky.social

30 Oct 2025

The State of Elixir Survey for 2025 is live! elixir-survey.typeform.com/2025-edition Fill it out if you have any connection to the Elixir ecosystem. It really helps us understand what happens. Curiosum are awesome to run this for the community. #elixirlang

elixir-survey.typeform.comCuriosum Elixir Survey 2025Elixir Survey 2025 by Curiosum - a global community survey collecting insights about how developers and teams use Elixir, their favorite tools, challenges, and expectations for the future of the…

14 Oct 2025

Sweet #Ecto datetime helpers? Yes, please! 😄 - ago, from_now, date_add, datetime_add 👨‍🍳🤌 #ElixirLang

elixirstreams.comElixir Streams |> What agents get wrong!Elixir and Phoenix tips, courses, and more.

9 Oct 2025

Alright... it's all up now 🎉 I walked through the Phoenix 1.8 AGENTS md file, and it was both funny and informative! You can see the full 25 mins of glory or in parts (on the same page) 👇 www.elixirstreams.com/tips/what-ag... #ElixirLang

German Velasco@germsvel.com

Getting back into recording **short** #ElixirLang video tips by recording a walk-through of @elixirphoenix AGENTS file... It's ~25 mins long. I think I'm rusty 😅

2 Oct 2025

Getting back into recording **short** #ElixirLang video tips by recording a walk-through of @elixirphoenix AGENTS file... It's ~25 mins long. I think I'm rusty 😅

germanvelasco.comBreak apart your features into full-stack slicesOur communication practices can be very disrupting. Remote work has taught me to be more considerate of how I communicate with others. We should treat other people's time as we like ours to be treated...

2 Oct 2025

Anybody using #ElixirLang in production and doesn't like their error tracking service/APM service? Would you be willing to jump on a 30 min call today and show me what you like/dislike about it? 🙏

German Velasco reposted

JEG2

@jeg2.me

1 Oct 2025

Don’t let the age of this article from @germsvel.com scare you off, vertically slicing features is still a great idea: www.germanvelasco.com/blog/break-a... #AgileDevelopment

18 Sept 2025

Hypothetically speaking... if I were to build an Elixir-focused error and performance tracking tool, what would you like to see in it? 🧐 #ElixirLang