Invariant Testing Bootcamp
Go from zero to hero in using stateful fuzzing to secure and break smart contracts

Overview
In the Recon x RareSkills Invariant Testing Bootcamp, you’ll go from zero to hero in using stateful fuzzing to secure and break smart contracts.
You’ll learn:
- The philosophy and mental models behind fuzzing
- How to set up projects for meaningful testing
- How to drive toward high coverage
- How to identify and write high-impact invariants
The bootcamp is paced for professionals with a day job and is structured to guide participants through fuzzing an entire protocol from scratch. Optional advanced assignments are available for those who want to go deeper.
Invariant Testing Bootcamp syllabus
Each week, there will be one hour of live class and one hour of office hours with the instructor. Both sessions will be recorded, but you shouldn’t miss them, as they are designed to be highly interactive.
The purpose of the office hours is for students to ask questions, review homework, and discuss in more detail the topics presented in class. Students on the premium plan can schedule weekly one-on-one meetings with the instructor.
Week 1
Getting Started
Introduction to invariant testing, stateful vs. stateless fuzzing, differences between Foundry, Echidna, and Medusa, an overview of Chimera, and scaffolding your first ERC-4626 vault.
Week 2
Scaffolding Real Protocols
Scaffolding production-grade protocols (e.g., Morpho Blue), coverage-first methodology, corpus reuse, mocking oracles and IRMs, clamping for faster coverage, and dynamic deployments.
Week 3
Managers and Property Types
Multi-actor and multi-token setups, AssetManager and ActorManager patterns, and deep dives into Global, Inlined, and Doomsday properties.
Week 4
Writing Properties
The five property classifications (Valid States, State Transitions, Variable Transitions, High-Level Properties, and Unit Tests), ghost variables, try/catch patterns, and systematic debugging of failing properties.
Week 5
Weakest Precondition
Formal verification vs. fuzzing, symbolic storage, proving properties with Halmos, and understanding when each approach is the right tool.
Your Instructor

Alex The Entreprenerd
Alex The Entreprenerd a well known Lead Security researcher. Co-founder of Recon, former SC Dev for Badger having written code that handled Hundreds of Millions TVL. He received $500k in awards for bug bounties and security contest and prevented $20 MLN in from being stolen on mainnet. About Recon: Recon is a team of invariant testing engineers and security researchers. Our goal is to make invariant testing a baseline for all projects building on the EVM. By the numbers: $3B+ TVL protected. $20M+ funds saved in 2025. 12,500+ cloud fuzzing runs, breaking over 7k properties. Invariant Testing extension with over 1000 downloads.
Invariant Testing Bootcamp Pricing
$1,500
/ Upfront- 5 × Weekly Live Classes and Office Hours
- Tailored Homework
- Access to the RareSkills Slack & Discord Community (Lifetime Access)
Frequently Asked Questions
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