Skip to main content
5 Weeks of Online Classes

Invariant Testing Bootcamp

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

Next Cohort:
May 12, 2026 at 9:00 AM EDT

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

Last updated on Dec, 2025

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

Course 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.

Flexible Plans

Invariant Testing Bootcamp Pricing

Next Cohort:
May 12, 2026 at 9:00 AM EDT
Save 2% if you pay with USDC or USDT

$1,500

/ Upfront
  • 5 × Weekly Live Classes and Office Hours
  • Tailored Homework
  • Access to the RareSkills Slack & Discord Community (Lifetime Access)
Everything You Need To Know

Frequently Asked Questions

Unlock Your Potential

Job Opportunities

Smart Contract Engineer

Smart Contract Engineer

Category Labs is looking for a Smart Contract Engineer to join the core engineering team to build at the application layer.

Senior Protocol Engineer

Senior Protocol Engineer

Join us as a Senior Protocol Engineer at Sorella Labs, where you will be instrumental in architecting and engineering a first-of-its-kind decentralised trading system at the forefront of MEV-aware application design.

DeFi Risk & Strategy Lead

DeFi Risk & Strategy Lead

You will be the single owner of our risk and strategy function. From researching new yield opportunities to designing leveraged positions, building risk frameworks, conducting due diligence on protocols, and monitoring everything in real-time.

Growth Lead

Growth Lead

We're seeking a growth lead to scale HyperLink's adoption, TVL, and partner ecosystem.