Solana Programs and Anchor

Solana's Core Architectural Choice

Solana made a different bet from Ethereum: optimise for throughput by requiring transactions to declare which accounts they touch up front. This declaration enables Sealevel — Solana's runtime — to schedule non-conflicting transactions in parallel. Result: high throughput (theoretical 65,000 TPS, sustained 3,000-5,000 TPS in practice) at the cost of higher developer complexity. You can't just 'call whatever contract you want' the way you can on Ethereum; you have to know your account list in advance.

Programs Aren't Contracts

On Solana, smart contract logic lives in 'programs.' Programs are stateless — they don't hold their own data. Data lives in separate 'accounts' that programs can read from and write to. This separation is a big mental shift from Ethereum, where contracts and their state are tightly coupled. The benefit: programs can be upgraded independently of their data, and the same program logic can operate on many independent account instances.

Anchor — The Framework Everyone Uses

Anchor is the dominant Solana development framework, similar in role to Hardhat or Foundry on Ethereum. It provides Rust macros that abstract away most of the account-handling boilerplate, IDL (Interface Description Language) generation for client SDKs, and testing utilities. Most production Solana programs are written in Anchor. The framework's adoption is so widespread that 'Solana program' and 'Anchor program' are essentially synonymous for new development.

• Transactions declare account list up front → enables Sealevel parallel execution
• Programs are stateless; data lives in separate accounts
• Written in Rust, with C/C++ support; Anchor framework dominates
• High throughput at the cost of higher developer complexity