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Oliver Flatt

PROFILE

Oliver Flatt

Worked on the cedar-policy/cedar-spec and cedar repositories to deliver architectural and performance improvements for policy engine evaluation. Focused on implementing batched evaluation algorithms and formal verification to ensure well-typedness and correctness, using Rust and Lean for both system design and theorem proving. Introduced on-demand entity loading and refined type systems, simplifying internal representations and error handling to support large-scale authorization scenarios. Emphasized maintainability and reliability by consolidating evaluation logic, removing edge-case handling, and adding robust tests. The work reduced runtime errors, improved scalability, and aligned the codebase with business goals for reliable, efficient policy evaluation and language evolution.

Overall Statistics

Feature vs Bugs

100%Features

Repository Contributions

7Total
Bugs
0
Commits
7
Features
4
Lines of code
7,739
Activity Months2

Your Network

21 people

Work History

September 2025

4 Commits • 3 Features

Sep 1, 2025

In September 2025, delivered scalable batched evaluation capabilities across cedar-policy/cedar-spec and cedar, with formal proofs, type refinements, and robust tests, enabling on-demand entity loading and improved reliability for large-scale authorization. Key changes include batched evaluation correctness proofs, EntityLoader refinements, removal of absent-case handling for partial entities, and a clearer internal type vocabulary. These workstreams reduce runtime errors, improve performance on large datasets, and align code with business goals of reliability, scalability, and maintainability.

August 2025

3 Commits • 1 Features

Aug 1, 2025

August 2025 — Cedar-spec: delivered key architectural and performance improvements to the Policy Engine Evaluation, with batch loading and formal verification to ensure residual well-typedness. Focused on measurable business value and reliability; no major bugs fixed this month as the emphasis was on delivering robust features and solidifying the evaluation path. The work lays groundwork for faster policy evaluations and safer policy language evolution.

Activity

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Quality Metrics

Correctness97.2%
Maintainability94.4%
Architecture97.2%
Performance81.4%
AI Usage20.0%

Skills & Technologies

Programming Languages

LeanMarkdownRust

Technical Skills

API DesignAlgorithm DesignCodebase MaintenanceCompiler DesignData StructuresError HandlingFormal VerificationFunctional ProgrammingOptimizationPolicy EvaluationRefactoringSystem DesignTestingTheorem ProvingType Systems

Repositories Contributed To

2 repos

Overview of all repositories you've contributed to across your timeline

cedar-policy/cedar-spec

Aug 2025 Sep 2025
2 Months active

Languages Used

Lean

Technical Skills

Algorithm DesignCompiler DesignData StructuresFormal VerificationFunctional ProgrammingOptimization

cedar-policy/cedar

Sep 2025 Sep 2025
1 Month active

Languages Used

MarkdownRust

Technical Skills

API DesignCodebase MaintenanceError HandlingPolicy EvaluationRefactoringSystem Design