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121: Benedikt Deicke - Building Userlist.io

50 min episode · 2 min read
·
Benedikt Deicke

Episode

50 min

Read time

2 min

Topics

Productivity, Software Development, Science & Discovery

AI-Generated Summary

Key Takeaways

  • Server-side integration strategy: Userlist requires server-side API calls instead of JavaScript snippets to ensure reliable tracking without ad blockers, browser limitations, or third party cookie restrictions affecting data collection and automation triggers for customer onboarding sequences.
  • Dynamic segmentation architecture: User segments compile from abstract syntax trees stored as hashes in the database, using Rails AREL to generate SQL queries dynamically. This allows complex nested conditions like email filters combined with event frequency tracking across custom time periods.
  • Workflow execution model: Campaign automations execute as background jobs that process one node at a time, scheduling the next step only after completion. This just-in-time approach allows campaign modifications to affect users mid-sequence without re-queuing all future emails.
  • Email deliverability preparation: SparkPost integration separates customer accounts into subaccounts to prevent one bad actor from damaging deliverability for all users. Custom domain authentication with DKIM is optional but recommended, defaulting to userlistmail.com sending addresses for immediate functionality.

What It Covers

Benedikt Deicke explains building Userlist.io, a SaaS-focused email automation platform, covering technical architecture choices including Rails backend, Ember frontend, server-side integration strategy, dynamic SQL query generation from abstract syntax trees, and workflow engine implementation.

Key Questions Answered

  • Server-side integration strategy: Userlist requires server-side API calls instead of JavaScript snippets to ensure reliable tracking without ad blockers, browser limitations, or third party cookie restrictions affecting data collection and automation triggers for customer onboarding sequences.
  • Dynamic segmentation architecture: User segments compile from abstract syntax trees stored as hashes in the database, using Rails AREL to generate SQL queries dynamically. This allows complex nested conditions like email filters combined with event frequency tracking across custom time periods.
  • Workflow execution model: Campaign automations execute as background jobs that process one node at a time, scheduling the next step only after completion. This just-in-time approach allows campaign modifications to affect users mid-sequence without re-queuing all future emails.
  • Email deliverability preparation: SparkPost integration separates customer accounts into subaccounts to prevent one bad actor from damaging deliverability for all users. Custom domain authentication with DKIM is optional but recommended, defaulting to userlistmail.com sending addresses for immediate functionality.

Notable Moment

Deicke reveals the hardest technical challenge was not the backend workflow engine or SQL query generation, but creating a non-technical friendly UI that translates complex nested filter conditions into visual representations users can understand and modify without editing raw JSON.

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Episode Transcript

In this episode of Fullstack Radio, I talked to Benedict Daika about building userless.io, a new email automation platform designed for SaaS businesses that he recently launched with his cofounder. This is Fullstack Radio episode 121. Hey, Hey, everyone. Welcome to another episode of the Fullstack Radio podcast. I'm your host, Adam Wadden. And today, it's my pleasure to be speaking with Benedikt Dica, who is, the lead developer, I guess, on, userless.io. How's it going, Benedikt? Yeah. Everything going right. Thanks Thanks for having me. Yeah. So the reason I want to have you on the show is it's always fun to do these episodes where we just kinda do, a deep dive into how someone built a new product that they've put out. And it feels like it's been a while since we've done one. And, you and Jane just recently launched UserList and, it's a pretty interesting app and I've seen a lot of people saying lots of good things about it. So I thought it would be cool to talk a little bit about, what it does and dive into some of sort of the interesting technical challenges and stuff behind building it. Yeah. Sure. Sounds good. So I guess for anyone who isn't familiar with you, do you mind just introducing yourself first of all? Yeah. Sure. So my name is Benedict. I'm you said lead developer. It's funny because I'm the only developer. So I'm kinda leading myself, but I'm I'm the the engineering cofounder of userlist.io. We are a customer messaging tool for software as a service applications. Basically, we allow you to track, what your users are doing inside your application and then send them messages based on that or send them messages when they don't do a certain thing. And, yeah, I think that's the gist of it. Like, just, moving data around and reacting to it. Awesome. Yeah. So I guess maybe something to talk about at first would just be, kinda like what makes user lists sort of a little bit different maybe from other, email marketing automation tools that people are sort of used to because it sounds like user list is sort of focused on a more specific use case where someone might use an existing tool like Drip or something for this as as well, but those tools are a lot more sort of general purpose. Whereas, I think, from my understanding anyways, user list is sort of designed for a more specific need that it can sort of optimize the workflow for a little bit. So can you give an example of how someone might use user list in their business? Sure. So our main focus is, as I said, software as a service applications. So we only have an API. We don't have any anything like forms that you can put on your website or embed somewhere. So all the data we process is sent from your application into ours or via the integr …

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  • Userlist.ioBy guest
    Benedikt Deicke explains building Userlist.io, a SaaS-focused email automation platform, covering technical architecture choices including Rails backend, Ember frontend, server-side integration strategy, dynamic SQL query generation from abstract syntax trees, and workflow engine implementation.
  • Sponsors: DigitalOcean
  • Sponsors: Cloudinary
  • SparkPost integration separates customer accounts into subaccounts to prevent one bad actor from damaging deliverability for all users.

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