Jonathan Bundi

Finding vulnerabilities so others don't have to.

[Jonathan Bundi @Jonathan_W3b]

Day 30 of my smart contract journey
Today I started on my interactions script, I'm halfway done
#smartcontracts #foundry #web3

[Jonathan Bundi @Jonathan_W3b]

Day 29 of my Smart Contract Security Researcher journey 🔐
Created a HelperConfig script to separate network configs from deployment logic. Supports Sepolia and Anvil, and spins up VRFCoordinatorV2.5 + LINK mocks locally for testing.
#Solidity #SmartContracts #Foundry

[Jonathan Bundi @Jonathan_W3b]

Day 28 of my Smart Contract Security Researcher journey 🔐
Refactored my winner selection logic to avoid duplicates.
Used a swap and shrink approach where I pick a random index, store the winner, replace it with the last eligible member, then shrink the array.
#SmartContracts

[Jonathan Bundi @Jonathan_W3b]

Day 27 of my Smart Contract Security Researcher journey 🔐
Today I implemented fulfillRandomWords to handle the randomness callback.
The function filters eligible members, selects random winners, calculates the payout, updates state, and then distributes the rewards.
#Chainlink

[Jonathan Bundi @Jonathan_W3b]

Day 26 of my Smart Contract Security Researcher journey 🔐
I implemented checkUpkeep and performUpkeep.
checkUpkeep verifies conditions like time passed, DAO state, treasury balance, and enough eligible members.
If everything is true performUpkeep triggers the next step.
#Web3

[Jonathan Bundi @Jonathan_W3b]

Day 25 of building 🚀

Today I focused on testing the DAO membership logic.
I implemented and wrote tests for the joinDAO and leaveDAO functions to ensure: • Users can successfully join the DAO
• Members can leave correctly
• State updates happen as expected
#SmartContracts

[Jonathan Bundi @Jonathan_W3b]

Day 24 of my Smart Contract Security Researcher journey 🔐
Today I learned about gas-efficient array removal using swap and pop.
Without shifting the entire array you swap the element to remove with the last one and then pop() the array.

#SmartContracts #Foundry

[Jonathan Bundi @Jonathan_W3b]

Day 23 of my Smart Contract Security Researcher journey
Today I finalized the idea for the project I’ll be building next using the knowledge from the Foundry Fundamentals course
It involves automation, randomness, and a treasury system working together on-chain.🥳
#SmartContracts

[Jonathan Bundi @Jonathan_W3b]

Day 22 of my Smart Contract Security Researcher journey 🔐
I officially finished the Foundry Fundamentals course
Didn’t deploy to testnet yet but that’s intentional.
Next step: build my own project from scratch using everything I’ve learned then deploy it.

#SmartContracts

[Jonathan Bundi @Jonathan_W3b]

Day 21 of my Smart Contract Security Researcher journey 🔐

Missed two days, but consistency > perfection.
Today: created an interaction script to programmatically create a VRF subscription with Chainlink.
Broadcast ➡️ createSubscription() ➡️ return subId ➡️ update config.
#Web3

[Jonathan Bundi @Jonathan_W3b]

Day 20 of my Smart Contract Security Researcher journey 🔐
Slow day, but progress is progress.
Started writing unit tests for my contracts today
Security starts with testing.
#SmartContracts #Solidity #Web3

[Jonathan Bundi @Jonathan_W3b]

Day 19 of my Smart Contract Security Researcher journey

Today I built a HelperConfig contract to manage multi-network configurations (Sepolia + local Anvil) and deployed a VRFCoordinatorV2_5 mock for local testing.
Also wrote a deployment script.
#SmartContracts

[Jonathan Bundi @Jonathan_W3b]

@xfz_eth Yeah you can start on cyfrin updraft blockchain basics then follow @Web3_Vinay roadmap

[Jonathan Bundi @Jonathan_W3b]

Day 18 of my Smart Contract Security Researcher journey 🔐
Rebuilt my Raffle contract from scratch using Chainlink VRF + Automation.
Now I truly understand enums, upkeep logic, and the full randomness flow.
Rebuilding without copying.
#SmartContracts #Web3Security

[Jonathan Bundi @Jonathan_W3b]

Day 17 of my Smart Contract Security Researcher journey 🔐
Today I learned how to automate a lottery using Chainlink Automation
Now the contract automatically picks a winner and restarts the lottery once the previous round is complete.
No manual intervention.
#SmartContracts

[Jonathan Bundi @Jonathan_W3b]

Day 16 of my Smart Contract Security Researcher journey 🔐

Learned a key step in using Chainlink VRF for verifiable on-chain randomness 🎲
Understanding the request → callback flow is crucial for secure lotteries and games.
Leveling up daily.

#SmartContracts #Solidity #Web3

[Jonathan Bundi @Jonathan_W3b]

@alexabelonix Thanks for sharing this opportunity. I’m currently building my smart contract security skills using Foundry and documenting my journey publicly. I’m still early in my path, but I’m very committed to learning and contributing.

[Jonathan Bundi @Jonathan_W3b]

Day 15 as a Smart Contract Security Researcher 🚀
Busy month with exams but I pushed code to my first repo.
Built and tested a small contract using Foundry fundamentals.
Check it out: https://t.co/ux6r1F8UUJ
#SmartContracts #Blockchain #Foundry

[Jonathan Bundi @Jonathan_W3b]

Just finished my Bsc Science exams today picking up where I left.
#smartcontracts #securityresearcher

[Jonathan Bundi @Jonathan_W3b]

Day 14 of my smart contract security researcher. I'll be rereading my previous while I revise for my campus exams next week.