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Insights on smart contract security, invariant testing, and fuzzing from the Recon team.
AI Smart Contract Audits: Beyond the Hype
Everyone claims AI auditing. Most mean they ran an LLM on your code. Here is what AI-powered smart contract auditing actually looks like when built on top of invariant testing and formal methods.
Towards the Scientific Audit
Audits today are artisanal. Two auditors reviewing the same code follow different paths and produce different results. This inconsistency is the gap attackers exploit. Here is how we make audits scientific.
From Zero to Fuzzing: A Beginner's Guide to the Chimera Framework
A hands-on beginner tutorial for the Chimera framework. Go from an empty project to running invariant tests with Foundry, Echidna, and Medusa — no prior fuzzing experience required.
The True Cost of Not Auditing: Lessons from $20M+ in Prevented Losses
DeFi lost over $1.7 billion to exploits in 2024. Here is the business case for auditing, backed by real data from Recon engagements that prevented over $20M in potential losses.
Stateful Fuzzing Explained: Why Sequence Matters in Smart Contract Testing
Most smart contract bugs only manifest after a specific sequence of transactions. Stateful fuzzing explores these sequences automatically — here is how it works and why it matters.
What to Expect from a Smart Contract Security Audit in 2025
The smart contract audit has evolved far beyond a manual code review. Here is what a modern audit looks like in 2025 — and what you should demand from your auditor.
Understanding Rounding Errors in DeFi: How Small Bugs Lead to Big Exploits
In Solidity, there are no decimals — only integers and the illusion of precision. Learn how 1 wei rounding errors compound into protocol-draining exploits and how to defend against them.
How to Set Up Continuous Security Testing with CI/CD and Fuzzing
Stop treating security as a one-time audit. Learn how to integrate Chimera-based fuzzing into your CI/CD pipeline with GitHub Actions so every pull request gets fuzzed automatically.
5 Smart Contract Vulnerabilities That Unit Tests Will Never Catch
Unit tests check what you expect. But the most dangerous vulnerabilities hide in the unexpected — cross-function reentrancy, rounding accumulation, and more. Here are five categories unit tests will never catch.
Echidna vs Medusa: A Practical Comparison for Security Researchers
A hands-on comparison of Echidna and Medusa for smart contract fuzzing. We cover performance, configuration, corpus management, and when to choose each tool.
Property Design Patterns for DeFi Lending Protocols
A practical catalog of invariant property patterns for lending protocols — from solvency and utilization bounds to liquidation health checks — with Solidity code for each.
The Anatomy of a Critical DeFi Bug: Insolvency Through Incorrect Accounting
A single rounding error in share accounting can drain an entire vault. Walk through the anatomy of a real critical DeFi bug and learn why invariant testing is the only reliable way to catch it.
Getting Started with Recon Pro Cloud Fuzzing
A step-by-step guide to running your first cloud fuzzing campaign with Recon Pro. Go from zero to fuzzing in minutes, with no infrastructure to manage.
How We Found Real Vulnerabilities with Fuzzing
A technical deep-dive into real vulnerabilities we've found through fuzzing, from critical accounting bugs to subtle rounding exploits. Includes the properties that caught them.
Why Invariant Testing Matters for DeFi Security
Unit tests check what you think of. Invariant tests check what you don't. Here's why every DeFi protocol needs invariant testing and how it has saved millions in real engagements.