Polkadot is a highly innovative blockchain protocol that focuses on issues related to scalability and interoperability. The platform has positioned itself as a viable alternative to Ethereum, attracting significant interest from developers, investors, and crypto enthusiasts.
Polkadot’s Relay Chain does not support smart contracts natively. However, parachains, the Layer1 blockchains that run in the Polkadot ecosystem, come with smart contract support.
What Are Polkadot Smart Contracts?
Polkadot smart contracts are self-executing contracts that have a set of predetermined rules and conditions. These smart contracts are generally written in Rust, the programming language used by the Substrate framework. The Substrate framework is custom-built to develop parachains in the Polkadot ecosystem. Smart contracts on Polkadot allow developers to create dApps (decentralized applications) and execute programmable logic. They also facilitate completing different functions, including token transfers, governance mechanisms, and decentralized finance (DeFi) protocols.
Polkadot smart contracts can interact with the Polkadot ecosystem and leverage its shared security and interoperability. However, Polkadot’s Relay Chain does not support smart contracts. Instead, parachains in the Polkadot ecosystem come with smart contract support.
Writing A Smart Contract On Polkadot
When developers write a smart contract on Polkadot, they create a set of instructions associated with a specific chain address. When creating a smart contract, developers must consciously develop upgradeability, and the contract is deployed on a target chain that has its own environment. Smart contracts must also limit their execution; otherwise, they could consume the computational resources of a chain and prevent others from using it.
As mentioned, the Relay Chain does not come with native smart contract support. However, parachains connected to the Relay Chain can and do support smart contracts. Substrate supports smart contracts in the following ways,
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The EVM pallet by Frontier
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The Contracts pallet is offered by the FRAME library. These can be used for WASM-based contracts.
Frontier EVM Contracts
The Frontier suite allows a Substrate-based chain to run Ethereum contracts natively with the same API/RPC interface. It also enables Ethereum addresses to be mapped directly to and from Substrate’s SS58 scheme.
Substrate Contracts
Substrate offers developers a built-in contract pallet. On the other hand, parachains can also support WebAssembly smart contracts. The EVM Pallet allows parachains to implement the Ethereum Virtual Machine (EVM), which supports direct ports of Ethereum smart contracts.
Contracts Pallet
Developers are generally more familiar with deploying to an EVM-based chain. The Contracts Pallet significantly improves the design of the EVM.
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WASM - The Contracts Pallet uses WebAssembly as its compilation target. Developers can write smart contracts using any language that compiles to WASM.
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Deposit - Smart contracts must hold a deposit (ContractDeposit) large enough to justify their existence on the chain. Contract deployers must deposit the ContractDeposit into the new contract over and above the ExistentialDeposit.
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Caching - All contracts are cached by default. They must be deployed only once, and once deployed, they can be instantiated as many times as required. This keeps the storage load on the chain at a minimum. Additionally, the code will be erased from storage when the contract is no longer in use.
Advantages Of Developing Smart Contracts On Polkadot
Polkadot gives developers an unprecedented level of interoperability. Web apps on Polkadot become inherently interoperable with other parachains in the Polkadot ecosystem. There are several other advantages of developing smart contracts on Polkadot.
Harnessing The Relay Chain
Developing smart contracts on Polkadot allows developers to harness the capabilities of the Polkadot Relay Chain, including scalability, consensus mechanisms, shared security, and governance.
Greater Security
Smart contracts on Polkadot are able to leverage the security of the underlying blockchain.
Optimization And Flexibility
Polkadot gives developers a high degree of flexibility, eliminating challenges arising from optimizing diverse use cases.
Seamless Upgrades
Polkadot allows developers to perform seamless and timely upgrades to their smart contracts, ensuring they stay updated with the latest technologies and ensuring uninterrupted functionality.
Disclaimer: This article is provided for informational purposes only. It is not offered or intended to be used as legal, tax, investment, financial, or other advice.
