What is Solidity? Any Blockchain Developer Should Know

The rise of distributed ledger technology has redefined the concept of trust in the digital era, shifting from centralized, organization-based systems to code-based decentralized systems. In that context, Solidity is more than just a programming language; it is the “language of agreement” on the Ethereum platform and compatible virtual machines (EVMs). First designed by Gavin Wood in 2015, Solidity was created to fill the gap left by Bitcoin: the ability to execute complex, conditional logic on a permissionless network. Solidity's development is closely tied to Ethereum's evolution from a simple payments platform to a "global computer" capable of running large-scale financial, gaming, and governance applications. Any blockchain developer participating in the Web3 ecosystem today must face the reality that Solidity is the industry standard that cannot be ignored, bridging the gap between abstract mathematical ideas and the economic entities that execute on the blockchain. Building a complete dApp system does not stop at smart contracts but also requires support from professional web and application design units like Tan Phat Digital to optimize the end user experience.

Infrastructure Architecture and Operational Mechanism of Ethereum Virtual Machine (EVM)

To deeply understand Solidity, experts cannot separate this language from its unique execution environment its: Ethereum Virtual Machine (EVM). EVM is a Turing-complete virtual machine that operates as a decentralized operating system distributed across thousands of network nodes. The essence of EVM is a state machine that converts the global state of the blockchain through the execution of bytecode – a form of low-level binary code compiled from Solidity source code.

Bytecode and Opcodes Execution Mechanism

The process of executing a smart contract begins when a transaction is sent to the network. The EVM will perform the RLP (Recursive Length Prefix) decoding process, verify the digital signature, and then load the contract bytecode into memory for processing. Bytecode is essentially a series of opcodes, each occupying 1 byte, representing a specific computer operation. EVM is a stack-based machine, meaning it performs operations by pushing data into or pulling data from a stack with a maximum depth of 1024 items.

The main Opcode groups in the EVM architecture include:

Stack Group: Includes PUSH1-32, POP, DUP, SWAP. The function is to coordinate data on top of the stack and support 256-bit data words suitable for cryptographic encoding.
Arithmetic Group: Includes ADD, SUB, MUL, DIV, MOD. Perform arithmetic calculations; Versions after 0.8.0 have built-in overflow checking.
Logic and Comparison Group: Includes EQ, LT, GT, AND, OR, XOR. Supports bitwise logic and conditional structures needed for program branching.
Storage Group (State): Includes SSTORE, SLOAD. Interact directly with the blockchain's permanent state; these are the most expensive Gas operations.
Flow Control Group: Includes JUMP, JUMPI, PC. Navigate execution based on logical conditions; foundation for loops and if-else statements.
Cryptographic Group: Includes SHA3 (KECCAK256). Computes the hash function directly on the chain, a core element of data integrity.

Each data word in the EVM is 256-bit in size. This design is optimized for Elliptic curve operations and hashing algorithms such as Keccak-256. However, the use of large data words also poses gas challenges when dealing with smaller data types, leading to the need for variable packaging techniques in storage.

Data Management and Memory Hierarchy

Solidity's memory architecture is divided into four distinct areas, forcing developers to have a strict resource management strategy:

Storage permanent):Where the contract's state variables are stored. Data in Storage is written directly to the blockchain and exists forever. Gas cost for writing to Storage (SSTORE) is extremely high.
Memory: Exists as a linear array of bytes and exists only during the execution of a function. Memory is cheaper than Storage, but the cost increases quadratically based on the capacity used.
Calldata (Input Data): Read-only memory area, containing parameters sent with the transaction. Calldata is the cheapest area to store temporary data because it cannot be modified by the contract's source code.
Stack: Used for immediate calculations and storing small local variables. Stack has a limit of 1024 items, if exceeded it will cause "Stack too deep" error.

Intensive Programming Syntax and Language Features

Solidity is a statically typed language. Its syntax resembles C++ in class structure, JavaScript in function definition, and Python in polymorphic inheritance. To connect these logics with users, businesses often look to units like Tan Phat Digital to deploy professional web applications, making it easier to interact with smart contracts.

Special Variables and Data Type System

In addition to common data types, Solidity introduces the address data type – representing the wallet or contract address. An address can be appended with the payable attribute, allowing it to receive Ether directly. Common global variables include msg.sender (function caller), msg.value (send amount), and block.timestamp (block time).

Visibility and Access

Setting access permissions correctly is extremely important. Solidity defines four levels of visibility:

Public: Functions can be called from inside and outside the contract.
External: Can only be called from outside, usually more gas-efficient than public when dealing with large arrays.
Internal: Accessible only from within the current contract or next subcontract redundant.
Private: Accessible only within the contract that defines it.

Smart Contract Design Patterns and Advanced Features

Design patterns are technical solutions to overcome the limitations of the blockchain network.

Proxy and Factory Design Patterns

Because contracts are not Modifiable after deployment, the Proxy design pattern (using delegatecall) allows logic and storage to be separated, allowing for feature upgrades without changing contract addresses. Factory Pattern allows one contract to create other sub-contracts dynamically, like how Uniswap creates new trading pairs.

Common Token Standard

ERC-20 (Fungible Token): Interchangeable tokens, used for Stablecoins or Governance Tokens.
ERC-721 (Non-Fungible Token): Each token is unique, for NFT art or virtual real estate.
ERC-1155 (Multi-Token Standard): Manage both fungible and non-fungible tokens in a single contract to optimize gas.
ERC-4626 (Tokenized Vaults): Standardize yield storages in DeFi.

Security and Defense Strategies

Security is a top priority in Solidity programming. A small mistake can lead to irreparable financial loss. Popular defense strategies include following Checks-Effects-Interactions (CEI) rules to protect against Reentrancy attacks and using decentralized Oracles (like Chainlink) to prevent price manipulation via Flash Loans. Additionally, the Commit-Reveal mechanism is used to protect fairness against Front-running.

Multi-Chain Analytics and Tools Ecosystem

The choice of development tools greatly affects performance. The differences between current frameworks include:

Hardhat: Uses JavaScript/TypeScript, has a diverse plugin ecosystem, suitable for Full-stack Web3 developers.
Foundry: Written in Rust, allows writing tests in Solidity, faster execution speed and has tools like powerful Fuzz testing.

When expanding beyond Ethereum, developers can compare with other languages:

Solidity (Ethereum/L2): Medium difficulty, largest community, safety based on programming discipline.
Rust (Solana): Very high difficulty, extremely high performance thanks to parallel processing, excellent memory safety for.
Move (Aptos/Sui): High difficulty, resource-safe, very high performance.

Blockchain Labor Market in Vietnam

Vietnam is becoming a bright spot on the global blockchain map. Companies such as Sky Mavis and Kyber Network have affirmed their position in Vietnamese technology. The salary for blockchain programmers here is at a very attractive level:

Intern / Fresher (Under 1 year): 12,000,000 – 18,000,000 VND/month.
Junior (1 – 3 years): 25,000,000 – 45,000,000 VND/month.
Senior / ML Engineer (3 – 6 years): 60,000,000 – 100,000,000 VND/month.
Principal / Tech Lead (Over 6 years): 100,000,000 – 250,000,000+ VND/month.

To successfully convert from the traditional business model to Web3, businesses need a solid digital foundation. Units like Tan Phat Digital not only provide SEO standard website design services but also advise on customized Web App solutions, helping businesses get ready for the decentralized Internet era.

Roadmap to Become a Professional Blockchain Developer 2025

Phase 1: Learn the basics of cryptography, data structures and consensus mechanisms PoW/PoS.
Phase 2: Master Solidity syntax, ERC standards and memory management.
Phase 3: Proficient in using the framework (Foundry/Hardhat) and writing Unit Tests.
Phase 4: Research security, practice Audit and solve challenges such as Ethernaut.
Phase 5: Frontend integration (ethers.js, viem) to complete the E2E dApp application.

In short, Solidity is a mandatory starting point for anyone who wants to become a Blockchain Developer. With support from the community and professional technology partners like Tan Phat Digital, programmers and businesses can completely confidently enter the potential Web3 world.