No Vibes Allowed: Solving Hard Problems in Complex Codebases

9:31am - 9:50am | No Vibes Allowed: Solving Hard Problems in Complex Codebases

Speaker: Dex Horthy, CEO, HumanLayer

Speaker Profile: Full Speaker Profile

Bio: CEO, HumanLayer

Topic: Solving hard problems in complex production codebases where AI tools struggle

Links

https://github.com/humanlayer/humanlayer

@dexhorthy

Notes

• 12 factor agents in June
• Context engineering
• Does AI agents actually help
• 100K developers across all company sizes
• a lot of rework, working more just fixing the slop from last week
• how can we get the most out of data models
• we were shipping so much we had to change the way that we collaborate
• took 8 weeks
• research plan prompt system
• refresh context
• how do you know when it s time to start of
• “you’re absolutely right” — time to start over
• intentional compaction -> compress the context down to a markdown file
• what exactly, are we compaction
  • what takes up space in your context window
  • correctness
  • completeness
  • size
  • trajectory
• LLMs are stateless function
  • put better tokens in to get the right tokens out
• geoff huntly did a research
• “dumb zone”
  • around the 40% you are going to see diminishing turn
• use subagents
  • they are for controlling context
    • go find how this works (subagents)
• “build your entire plan around context workflow”
• “keep the context under 40%”
• DO NOT OUTSOURCE THE THINKING
  • it can only amplify the thinking that you’ve done
• spec driven development is broken
  • what does it mean
• semantic diffusion
• the code is like assembling now and just focus o the markdown
• “memento is the best movie on context engineering”
• “on demand compressed context”
• planning == leverage
• code review -> mental alignment
• this talk had twice as much slides as the time allows
• hardness engineering as a subset of ctxe
• hard part will be term work flow and update sdlc
• hiring to build an idea

Slides

Slide: 2025-11-21-09-35

Key Point: Demonstrates the significant adoption and growth of their open-source prompt library, using GitHub stars as a metric to show thousands of users have adopted their OSS prompts over approximately one year.

Literal Content:

• Left side: “Star History” graph showing humanlayer/humanlayer GitHub stars growth from October 2023 to October (current), showing exponential growth from ~1K to 7K stars
• Right side (on black background): “1000s of folks are using our OSS prompts”
• Footer: “no vibes allowed | @dexhorthy”
• Code Summit branding

Slide: 2025-11-21-09-37

Key Point: Appears to be a title or transition slide emphasizing their data-driven, evidence-based approach (“no vibes allowed”) - likely reinforcing the theme that their work is based on measurable results rather than hype or speculation.

Literal Content:

• Large text: “no vibes allowed | @dexhorthy”
• Code Summit branding

Slide: 2025-11-21-09-50

Key Point: Illustrates a structured, human-in-the-loop development process with three distinct phases (Research, Planning, Implementation), each requiring human review and incorporating revision cycles - emphasizing the importance of human oversight in AI-assisted development rather than fully autonomous coding.

Literal Content:

• Three parallel workflow diagrams showing:
  • Phase 1 Research: Research → Research Document → Human Review (with Revisions feedback loop)
  • Phase 2 Planning: Planning → Implementation Plan → Human Review (with Revisions feedback loop)
  • Phase 3 Impl: Impl → Clean Code → Human Review (with Revisions feedback loop)
• Author attribution: “JAKE NATIONS, SEP 04, 2025”
• Reference: “https://www.arthropod.software/p/vibe-coding-our-way-to-disaster”
• Footer: “no vibes allowed | @dexhorthy”