Building Streamslate: A Weekend Project Born from a YouTube Comment

•7 min read

Building Streamslate: A Weekend Project Born from a YouTube Comment

It started with a throwaway comment in a YouTube video. Last Friday evening, I was watching one of my favorite tech content creators review their streaming setup when they mentioned something that stuck with me: “I still haven’t found a PDF annotator with decent dark mode support.”

That single comment sent me down a rabbit hole that consumed my entire weekend—and resulted in Streamslate.

The Problem That Kept Me Up

As a developer who values the speed of AI and modern development tools, this seemed like the perfect weekend challenge. I immediately understood the frustration content creators face. Picture this: They’re in the middle of explaining a complex concept, their entire setup is perfectly dialed in with a sleek dark theme, and then they need to pull up a PDF whitepaper or documentation. Suddenly, viewers are blasted with a glaring white rectangle that completely breaks the immersion—not to mention what it does to their eyes after hours of streaming.

I couldn’t shake the thought. With the power of modern AI development tools, how hard could it be to build a PDF annotator that actually respects dark mode?

Turns out, it was the perfect challenge to tackle with AI assistance—complex enough to be interesting, but achievable in a weekend sprint.

Friday Night: The Itch I Had to Scratch

By 11 PM Friday, I had abandoned my original weekend plans. I’d already:

  • Surveyed every PDF annotator I could find (spoiler: they all treat dark mode as an afterthought)
  • Sketched out what a “dark-first” PDF tool might look like
  • Started a new project folder with that familiar mix of excitement and “what am I getting myself into?”

The core challenge became clear quickly: Most PDF tools invert colors in a way that makes documents look terrible. Blue links become orange, carefully designed diagrams turn into abstract art, and don’t even get me started on what happens to syntax-highlighted code blocks.

Saturday: Building the Foundation

I woke up Saturday with a clear vision: true dark mode isn’t about inverting colors—it’s about intelligent transformation. Streamslate needed to:

  1. Preserve document intent - If something is meant to stand out, it should still stand out in dark mode
  2. Handle images intelligently - Diagrams and screenshots shouldn’t become unreadable
  3. Make annotations pop - Highlights and notes need to be visible against dark backgrounds
  4. Stay out of the way - The UI should disappear until you need it

The technical approach crystallized around a few key decisions:

  • Electron for the desktop app - Native performance with web tech flexibility
  • Custom PDF rendering pipeline - Full control over how documents appear
  • Neon accent colors - High contrast annotations that work on dark backgrounds
  • WebSocket API from day one - Integration with streaming tools was non-negotiable

By Saturday evening, I had a working prototype that could load PDFs, apply intelligent dark mode transformations, and handle basic annotations. My test document? The PDF.js specification—because if it could handle that in dark mode, it could handle anything.

Sunday: The Marathon to MVP

Sunday was a blur of:

  • Building the annotation system (highlighting, freehand drawing, text notes)
  • Creating the “presenter mode” that removes all UI chrome
  • Implementing the WebSocket server for external control
  • Fighting with color math to get the dark mode transformations just right
  • Drinking an inadvisable amount of coffee

The breakthrough came when I realized that streamers don’t just need dark mode—they need their tools to be invisible until called upon. This led to the floating toolbar design that fades away when you’re not actively annotating, and the borderless window mode that makes the PDF feel like part of your stream overlay.

The “Aha!” Moment

Around 2 AM Monday morning, everything clicked. I was testing the OBS integration, had a PDF open in presenter mode with some highlights, and realized—this actually felt native to a dark streaming setup. No jarring transitions, no eye strain, just seamless annotation that looked like it belonged.

That’s when I knew this weekend project had turned into something real.

Why Dark Mode Matters

Building Streamslate taught me that dark mode isn’t just about aesthetics or reduced eye strain (though those matter). For content creators, it’s about:

  • Visual consistency - Your content should flow seamlessly
  • Viewer comfort - Nobody wants to be flashbanged during a late-night stream
  • Professional presentation - Cohesive visuals signal attention to detail
  • Accessibility - Many viewers actively seek out dark-mode content

What’s Next

What started as a weekend hack has grown into something I’m genuinely proud of. The response from the streaming community has been incredible—turns out, that YouTuber wasn’t alone in their frustration.

We’re now working on:

  • Stream Deck integration for quick annotation controls
  • More intelligent PDF transformations (better handling of scientific papers)
  • Collaboration features for co-streaming
  • A plugin system for custom workflows

The Technical Stack (for the Curious)

  • Frontend: React with TypeScript, styled for dark-first design
  • PDF Rendering: Custom pipeline built on PDF.js with color transformation layers
  • Desktop: Electron with native window management
  • API: WebSocket server for real-time control
  • Build: Webpack with some creative bundling for sub-10MB installers

Join the Dark Side

What started as a simple observation from a YouTuber has turned into something I’m genuinely proud of. This project really showcased the incredible speed of modern AI-assisted development. What might have taken weeks or months to build just a few years ago came together in a single weekend. The combination of AI code generation, modern frameworks, and a clear vision made it possible to go from idea to working product at an unprecedented pace.

If you’re a content creator tired of breaking your dark aesthetic every time you need to reference a PDF, give Streamslate a try. And if you’re a fellow developer exploring the possibilities of AI-accelerated development - sometimes the best ideas come from the most unexpected places.

And yes, it has really good dark mode.

Have a feature request or want to contribute? Join our Discord community or check out the GitHub repo. Let’s make PDF annotation actually work for content creators.