How Slingshot Built Cross-Chain Trading with Webhooks

Meet Slingshot: Revolutionizing On-Chain Trading

Slingshot is reimagining on-chain trading by combining DeFi's power with centralized exchange simplicity. Slingshot 2.0 supports instant trading of over 300,000 tokens across Solana, Ethereum, and various L2s. What sets them apart? Users can trade any token across any chain without worrying about bridging or gas fees - making DeFi trading as simple as possible. 

The challenge

As Slingshot built their new trading dApp, they faced a critical challenge: ensuring reliable deposit tracking across multiple blockchains. Their initial infrastructure required managing 40 different GCP services, with separate systems for EVM chains and Solana. This complex setup led to significant issues:

"Every other day, one of our nodes would fall behind and users would ask 'Hey, where's my deposit?' It was extremely stressful," shared the Slingshot team. The problem was particularly acute with Solana's short block times, and node inconsistencies frequently caused balance discrepancies that directly impacted user experience.

The result of the issues:

• Users would see their money leave their accounts, but not know where it went

• Slingshot team would be spending bandwidth fixing issues rather than building features

• New users would be turned off from trying the platform

Finding the Right Solution

After experiencing the limitations of managing their own infrastructure and evaluating several providers, Slingshot discovered that webhooks could transform their deposit tracking system. The key requirement was finding a provider that supported all their chains, especially Solana, under a single integration.

“We initially built deposit tracking for EVM chains - it was a pain to maintain, but it worked. But rebuilding that for Solana would have taken us a month (at least), especially with Solana's short block times.When we found out we could use webhooks for all chains through one provider, everything changed.”

"We wanted to use the same team for everything," explains the Slingshot team. "Some providers would work on a subset of chains, others on a different subset. But Alchemy reliably supported all the chains we needed." 

As a result, Slingshot uses Alchemy Webhooks to power their deposit tracking system, enabling unified multi-chain token balances while maintaining 100% on-chain, non-custodial operations.

The transformation

Webhooks instantly notify Slingshot of transactions across all chains - zero missed deposits.

In fact, Slingshot rebuilt their entire deposit tracking system using Alchemy Webhooks, replacing 40 GCP services with just 20 lines of code. The impact was immediate:

• Infrastructure simplified from 40 GCP services to a single integration

• Significant cost savings on infrastructure

• Complete system transition in just one week

• Consistent data accuracy across all chains

• Instant deposit confirmations for users

“I can finally sleep at night knowing there won't be missing deposits when I wake up," Clinton shared. "From the user's perspective, nothing is worse than depositing money into a new app and not seeing it show up. Now everything just works flawlessly.”

Building with World Class Engineering Support

A key factor in Slingshot's successful transformation was the hands-on engineering support they received throughout the process. "We were actually collaborating on the code itself," the team explains. "It wasn't just answering questions - the Alchemy team sent us code snippets, reviewed our implementation, and pointed out potential issues. I have never seen that level of support before in our space."

The technical collaboration proved especially valuable when dealing with complex cross-chain scenarios:

“When we shared our code, they dug into it and helped us optimize. Receiving support from engineers who thoroughly understand blockchain infrastructure made the integration so easy. We've spent countless hours trying to get support from other providers when things didn't work as expected, but Alchemy’s engineers blew us away with world-class support.”

This collaborative approach helped Slingshot maintain momentum during their development process. Their team quickly resolved technical challenges and implemented best practices, leading to a more robust solution within 1 week.

What's Next for Slingshot

With reliable deposit tracking in place, Slingshot is focusing on further adding features and expanding to additional networks. 

"We're excited to keep pushing the boundaries of what's possible in DeFi trading," says the team. "Making complex cross-chain trading simple and reliable for users is just the beginning."