Bridges are a road to nowhere for blockchain communications

Everybody knows blockchain bridges are broken. They’re widely recognized as one of the major risks of dealing in DeFi, exemplified by the Qubit, Ronin, and Wormhole exploits that stole hundreds of millions of dollars of investors’ money.

They suffer from multiple points of failure, yet they’re still widely used, making a mockery of anyone who claims blockchain transactions are somehow more “secure” than traditional finance.

Nonetheless, blockchain bridges have become a vital part of the DeFi and web3 ecosystem because it has morphed into a mishmash of independent networks. Bitcoin (BTC) has immense value and security, Ethereum (ETH) is home to the biggest selection of dApps, and Solana (SOL) is prized for its super-fast transactions. Due to this, there’s a need to be able to move assets from one chain to another. DeFi users who restrict themselves to a single network miss out on major opportunities, which is why interoperability is viewed as essential, even if it’s highly risky.

But what makes blockchain bridges so vulnerable? Mostly, it’s because they’re made up of multiple components, including validators, oracles, and custodians, which expose users to numerous attack vectors. These risks have been illustrated numerous times in the shape of smart contract hacks and validator takeovers. Moreover, even if the bridge itself is secure, hackers can still steal users’ funds through tricks like Border Gateway Protocol hijacking or exploiting the underlying network. With so many moving parts, it seems unlikely that bridges will ever be made secure.

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So, how can we remedy this?

We need to move away from this idea that bridges are somehow the best solution, and instead see blockchain interoperability for what it really is. It’s essentially about blockchain communication, or getting these networks to talk to one another, and there’s no hard-coded rule that we have to use a bridge.

A more promising system involves Chain Signatures, which were developed by HOT Labs and NEAR Protocol’s (NEAR) teams as a way for accounts to sign transactions on multiple blockchains. They utilize a decentralized multi-party computation network or MPC secured by staking to facilitate highly resilient cross-network communication.

Within an MPC network, multiple nodes collaborate to perform complex calculations while retaining full privacy over their computational outputs. In Chain Signatures, these MPCs are combined with NEAR accounts, which are unique from those on other blockchains because of their ability to control an unlimited number of sub-accounts that can act in the same way as smart contracts. These sub-accounts can therefore be used to manage programmable MPC calls and request individual nodes within these networks to sign transactions on third-party blockchains.

Because each of the MPC nodes works independently of the others and retains full privacy, Chain Signatures can distribute trust across multiple actors, ensuring that none of them has access to the full transaction data. When a NEAR account requests the MPC network to sign a transaction for another blockchain, it will utilize a key that’s shared by each of the MPC nodes to generate a cryptographic signature of that transaction, without exposing any of the details.

The only thing left to do is to safeguard this cryptographic key, and this can be done using something called “Trusted Execution Environments.” These are secure areas within computer processors that protect code and data from unauthorized access. They do this by isolating it from the main operating system and other processes, ensuring “confidential” transaction processing. We can use TEEs to safeguard the master keys for Chain Signature transactions. When a NEAR account requests the MPC network to sign a transaction, the data for that request goes into the TEE, which then spits out the digital signature that verifies the transaction. But the cryptographic key never leaves this safe and secure environment. As a result, this private key is never exposed, eliminating any possibility of unauthorized access.

Chain bridges change the game

We can see the implications of Chain Signatures and how they drastically ease cross-chain transactions. The level of abstraction they achieve makes the actual blockchain network more or less irrelevant to the end user in a number of dApps. For instance, Satoshi Protocol is a Bitcoin L2 rollup network that relies on Chain Signatures to power native BTC smart contracts to facilitate automated lending, with repayments, interest accrual, and rewards distribution. For the user, they won’t even notice they’re constantly sending and receiving funds from a second network.

There are more examples in the broader DeFi industry, such as RHEA Finance, a cross-chain yield farming and crypto trading protocol that’s built atop of the Chain Abstraction stack to initiate seamless transactions across DeFi ecosystems.

Besides DeFi, gas fee payments can also be simplified dramatically with Chain Signatures. With HOT Gas Refuel, users can pay gas fees on the BNB Chain using both NEAR and Tether (USDT) tokens, eliminating the hassle of acquiring BNB tokens.

Chain Signatures can also be implemented to simplify cross-chain staking. Allstake has developed a meshed restaking protocol that enables restaking across every blockchain by decoupling consensus and execution. Buying NFTs or non-fungible tokens is also dramatically simplified with Chain Signatures. The multichain, chain-abstracted NFT marketplace Mint has already demonstrated this by enabling NEAR wallets to buy and hold TON-based NFTs and Gifts, and more chains to come. All on top of the same Chain Abstraction engine.

It’s clear Chain Signatures are robust and flexible enough that they can become the foundational infrastructure that abstracts away the entire network for end users, including developers, giving rise to a seamless multichain future, where every single dApp is “chain-abstracted” by default. They completely eliminate the need for wrapped assets, trusted relayers, and intimate knowledge of how blockchains function, giving developers a unified API for building dApps that can interact with any network. It’s the simplest solution yet to blockchain interoperability.

It’s time to move beyond bridges

The web3 industry remains fixated on blockchain bridges as the ultimate enabler of cross-chain interoperability, but no one has yet been able to stamp out the numerous critical flaws in these architectures.

These days, there’s a lot of focus on so-called “trustless” bridges that eliminate the custodial risk factor by solidifying trust in code rather than humans. This means users don’t need to trust any third-party systems, but it doesn’t solve the risk of exploits in the underlying code. The industry needs to wake up to the fact that, so long as it relies on code to secure transactions, there will always be some level of risk because even the most solid and heavily audited implementations can be flawed.

That’s why Chain Signatures represent more than just a technical upgrade — they’re a foundational shift in how web3 thinks about interoperability. We’ve already reached the limits of what bridges can safely do. Chain Signatures move past this idea to fundamentally reimagine cross-chain access, not as an asset transfer, but as secure remote execution. And with this change in mindset, we can unlock a future where identity and intent move across chains, as opposed to the underlying assets.

With Chain Signatures, we no longer need to trust humans or code. Instead, we can distribute trust across multiple nodes and protect this with TEE-based key management, replacing single points of failure with an ironclad framework that will only break down if the whole system collapses. And there’s no way that’s ever going to happen.

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