Special thanks to Hooked project for their invaluable review and insightful contributions to this use case. Your expertise has been instrumental in refining and enhancing our work.

Challenges of Project that has frequent on-chain interactions

BNB Chain has demonstrated remarkable success in supporting high transaction volume projects, thanks to its lower costs and superior performance. Hooked is an excellent example, showcasing how BNB Chain's robust infrastructure can effectively manage significant transaction loads while maintaining efficiency and cost-effectiveness. However, for projects that require a large volume of on-chain interactions, the transaction costs of BNB Smart Chain may still be prohibitive, particularly when projects need to sponsor users' gas fees. Let's dive into the Hooked example to see how Hooked solved this challenge with a two layer architecture. 

Hooked is a gamified educational platform built on the BNB Chain, designed to simplify web3 technology for non-tech users. It is the World's 1st Web3 social learning platform, transforming over 10,000,000+ users. 

Hooked targets to provide a streamlined ramp up channel for non-tech savvy users to engage web3 world. So it allows users to login with google accounts to create their hooked wallet.

After login, users can participate in daily check-ins, and also finish quiz challenges to get rewards. After users achieve a milestone, they can be rewarded with a soulbound token NFT and in-app credits, which can be exchanged for on-chain tokens. 

Hooked Profile SBT is an SBT based on-chain proof of Web3 learning that serves as a credential and certification for learners educational achievements.  After users pass a requirements of learning, the achievements soulbound token will be minted to users. You can find the soulbound token contract here, which is on the opBNB network. 

Challenges of Hooked project faced 

Traffic Spikes:

• Popular campaigns lead to significant increases in traffic.
• Short periods of high traffic intensity.

For example, the average user interaction on the Hooked is around 300K in a single day, which can be efficiently handled, but if there is a campaign like popular learning course, or online training, the peak traffic can easily increase to 1K/seconds, which can impact user`s on-chain interactions.

Gasless Transactions:

• Gasless transactions necessary to reduce friction for users, which requires the project to sponsor the transaction cost for their users.
• Ensures seamless participation in platform activities.

Optimization Imperative:

• Infrastructure optimization crucial to handle sudden traffic surges.
• Maintaining smooth user interactions despite web3 complexities.

Execution Layer and DeFi Hub architecture

To solve the challenges mentioned above, the following architecture is being implemented by the Hooked project. 

Handle the traffic spike with lower cost

opBNB is the scaling solution of BNB Chain, it has higher throughput and lower gas fee. The block time of opBNB is 1 second, and the throughput is 100M gas per second, which can help Hooked project handle traffic spikes. At the same time, the much lower cost(<$0.001), Hooked project will pay less gas to users compared with BSC. 

The average transaction cost on the BNB Smart Chain (BSC) is approximately $0.20, which is lower than many other Layer 1 (L1) networks. However, for Hooked, with an average of 300,000 daily user on-chain interactions, the total cost for these activities, sponsored by the Hooked project, amounts to around $60,000 per day. By migrating their user interactions to a Layer 2 (L2) solution, Hooked can significantly reduce these costs to approximately $240 per day instead of $60,000.

Gasless solution on EIP4337

The gasless solution is facilitated through the Smart Contract Wallet, powered by EIP4337, which also functions as a wallet-as-a-service. This enables users to log in using their Google accounts to create a Hooked wallet on opBNB. Hooked social login and smart wallet is powered by the Particle Network, which provides the embedded wallet and integrates with the Google Authentication for users.

DeFi Hub on BSC

As users engage with Hooked educational campaigns, they gradually become accustomed to web3 concepts, fostering a greater comfort level with dApps and gas fee payments, which aligns perfectly with Hooked project objectives. Upon reaching milestones and successfully completing check-in and quiz tasks, users can convert their in-app credits into Hooked tokens or other BEP/EIP20 tokens through DeFi platforms like PancakeSwap and token info on CMC.

Users are responsible for covering the gas fees associated with these exchanges. Leveraging BSC as the asset layer is strategic, considering its prominence as the DeFi hub within the BNB Chain ecosystem.

Users can also trade Hooked tokens they earned from learning on CEX like Binance.

Summary

Onchain game or gamified projects usually has to handle very frequent on-chain interactions, and also needs to sponsor users to pay the gas. Therefore the cost of the chain is very sensitive for the projects.  

Hooked strategically opted for opBNB as its interaction layer due to its affordability, enabling the platform to sponsor new users' gas costs. Leveraging opBNB's higher capacity of 100M gas per second, Hooked can effectively handle traffic spikes during its campaigns.

Meanwhile, BSC serves as the asset layer for Hooked, tapping into its status as the DeFi hub of the BNB Chain. Users can seamlessly exchange their in-app credits for on-chain assets. With this integration, Hooked users have the opportunity to pay their own gas fees, opening doors to explore the diverse DeFi offerings within the BNB Chain ecosystem.