Impact Measurement in Retroactive Funding: Evolution Through RetroPGF 3-6

## The Measurement Challenge Retroactive funding promises to reward demonstrated impact, but measuring "impact" for public goods is notoriously difficult. Optimism has iterated significantly across rounds. ## Evolution Across Rounds ### RetroPGF 3 (January 2024) 30M OP to 501 projects - **Approach**: Badgeholder voting with minimal structure - **Categories**: OP Stack, Governance, Dev Ecosystem, End Users - **Challenges**: - 644 projects too many to evaluate thoroughly - Cross-category comparison difficult - Some gaming of profile presentation ### RetroPGF 4 (June 2024) 10M OP with focused scope - **Approach**: Narrowed to specific impact areas - **Improvements**: Better category definition, clearer criteria - **Results**: More consistent evaluation, still some subjectivity ### RetroPGF 5 (Fall 2024) 8M OP with refined process - **Focus**: Dev tooling and infrastructure - **Innovations**: - Impact metrics framework - Badgeholder training - Clearer evaluation rubrics ### RetroPGF 6 (Active) 2.4M OP focused on governance - **Scope**: Governance contributions only - **Approach**: Narrow focus allows depth - **New**: Algorithmic initial ranking ## Key Learnings 1. **Scope matters**: Narrower scope enables better evaluation 2. **Training helps**: Badgeholder preparation improves consistency 3. **Metrics + judgment**: Neither purely quantitative nor qualitative works alone 4. **Iteration required**: Each round informs the next ## Recommendations for Other Programs 1. Start with narrow scope and expand 2. Invest in evaluator training and support 3. Build impact measurement infrastructure 4. Plan for multi-round iteration