A Thank you to BuildBear

Thomas (BlockChief)
3 min readMar 19


I recently participated in the hackathon at ETHDenver and got the opportunity to meet tons of brilliant individuals. I was able to test out many new technologies that I hadn’t heard of before, some of which have drastically helped improve the efficiency of my development workflow.

My idea for the hackathon was an NFT raffle platform on Polygon. The concept behind the project was simple — sellers have the opportunity to create raffles, set their own unique ticket/supply parameters, and kickstart a new way of selling their NFT on the polygon ecosystem. Buyers have the opportunity to purchase tickets to these raffles, and potentially win an asset they otherwise might not have the liquidity for.

In order to properly test out the project, I needed to use NFTs deployed on the Polygon network. At first, I attempted to do most of my testing on Polygon’s Mumbai network, but it proved difficult to get legitimate NFTs in the format that I wanted. Most of them also had garbage information in their URI, making it challenging to test the project effectively.

That’s when I discovered BuildBear. I used this platform to create a fork of the Polygon mainnet for testing purposes. It made things way easier.

Here’s my experience using BuildBear:

1. Sign-up and Login: The sign-up and login process on BuildBear was smooth and quick, taking only a few minutes to get started.

2. Creating a Fork: Creating a fork of the Polygon mainnet was also straightforward and quick. I was able to do it at a specific block number to ensure I was testing with the right data.

3. Faucet for Test Tokens: To deploy and test my transactions, I needed native test tokens. Fortunately, BuildBear has a custom faucet that made it easy for me to get the tokens I needed without any hassle.

4. Impersonating an Account: I used a script to impersonate an account that had a lot of real-world NFTs, which I then transferred to my account on the private Polygon testnet. This allowed me to start staking the NFTs for the raffles.

5. User Testing: For my testers, I simply gave them the Faucet link, and they could mint their own native tokens for the gas. Once they had tokens, they could buy tickets for the raffles.

6. Calling the Draw: Once all the tickets were sold, I advanced the time until the expiration of the raffles and called the draw. It was that simple!

Overall, my experience with BuildBear was really good. I had some hesitations initially, but once I started using it, I ended up creating more than 10 private testnets for my testing. I also loved their block explorer, which gave clear detail into the success or failure of transactions

BuildBear is an excellent platform for anyone looking to test their blockchain applications or projects. I would highly recommend it to anyone looking to build on the EVM chain.

I’m happy to announce that our product won one of Chainlink’s bounties! We leveraged their VRF coordinator to help with true randomness when picking the raffle winner.

Here is a link to the demo video I recorded! The product will be released on Polygon’s mainnet in the coming days.