Last Week in Bitcoin (Sep 1-7, 2025)

Another @tuma weekly report, highlighting what happened at the bitcoin++ in Istanbul about Bitcoin scaling solutions. Here below the summary of the highlights of what developers and researchers have been working on, and presenting next-generation Bitcoin technologies. I was surprised to see what was presented. No mention Lightning.

Major Technology DevelopmentsMajor Technology Developments

BitVM and Zero Knowledge ProofsBitVM and Zero Knowledge Proofs

• Primary Focus: Improved bridging solutions between Bitcoin and sidechains/rollups using Zero Knowledge Proofs (ZKPs)
• BitVM Family: Multiple projects working to bring Bitcoin into decentralized finance (DeFi) applications
• Important Note: Many projects claiming to use "ZK" technology aren't actually implementing true zero-knowledge proofs

Garbled Circuits - The Game ChangerGarbled Circuits - The Game Changer

• Revolutionary Optimization: Garbled Circuits emerged as a key innovation for BitVM implementations
• Technical Breakthrough:
  • Current BitVM2 SNARK verifiers: ~4MB (size of entire Bitcoin block)
  • New Garbled Circuit verifiers: ~70KB (100x improvement)
• Future Development: Teams planning migration to BitVM3 implementations using Garbled Circuits

Ark ProtocolArk Protocol

• Core development teams presented Ark's scaling advantages and trade-offs
• Multiple discussions on how Ark could enhance Bitcoin scalability

Conference ResourcesConference Resources

Video ContentVideo Content

• Day 1 Presentations: YouTube Stream
• Day 3 Presentations: X/Twitter Broadcast

Hackathon ResultsHackathon Results

Competition DetailsCompetition Details

• Prize Pool: 5M satoshis
• Duration: 3-hour intensive development sprint
• Participants: 9 Bitcoin-focused teams
• Judging Criteria: Olympic gymnastics scoring system (difficulty, execution, overall effect)

WinnersWinners

1. 🥇 First Place: Artmak
   • Ark-based wallet implementation
   • Demonstrated Ark scalability testing
   • Also won "Best Design" award
2. 🥈 Second Place: CoreLLM
   • AI agent trained on Bitcoin codebase
   • Designed to help junior developers learn Bitcoin development
3. 🥉 Third Place: ZKPoor
   • Privacy-focused proof-of-reserves tool
   • Cryptographic verification without revealing addresses or UTXOs

Special Recognition AwardsSpecial Recognition Awards

• Best Use of STARKs: Bridgestr
• Reality-Check Award: MergeSyncPi

Technical ResourcesTechnical Resources

BitVM DocumentationBitVM Documentation

• BitVM: Official Website
• BitVM2: Documentation
• BitVM3: Research Paper

Related LinksRelated Links

• Hackathon Projects: DevPost Competition
• ZK Explainer Thread: Twitter Discussion

Research Topics DiscussedResearch Topics Discussed

• Bitcoin as base layer for peer-to-peer credit systems
• Bitcoin quantum computing considerations
• Privacy improvements through BitVM implementations
• Scaling solutions beyond traditional approaches