Browse all Token articles.

8 min read
Transfer and Approval Rules for ERC-721 Introduction This chapter continues as the third part (3/5) of our code walkthrough of OpenZeppelin’s ERC-721 CVL specification and focuses on token transfer...
Last updated on Feb 13, 2026
9 min read
Persistent Ghosts Introduction In previous chapters, we used ghost variables (via hooks) to record storage values and quantities that were not explicitly tracked in smart contracts — for example, the...
Last updated on Feb 13, 2026
12 min read
Partially Parametric Rules for ERC-721 Introduction This chapter is the final part (5/5) of the code walkthrough of OpenZeppelin’s ERC-721 CVL specification which formally verifies the following...
Last updated on Feb 13, 2026
10 min read
Mint and Burn Rules for ERC-721 Introduction ERC-721 is the Ethereum standard for non-fungible tokens, widely used to represent digital property. Like any form of property, it revolves around supply...
Last updated on Feb 13, 2026
14 min read
Invariants for ERC-721 Introduction In previous chapters, we explored how CVL invariants work: properties that must hold throughout all contract execution. Invariants can function as preconditions in...
Last updated on Feb 13, 2026
Components Part 2: OpenZeppelin ERC-20 Tutorial In Component Part 1, we learned how to create and use a component within a single file. We built a from scratch and integrated its storage, events, and...
Last updated on Dec 11, 2025
15 min read
Cairo Storage Variable Types In Starknet, Contract Storage is the persistent memory where your smart contract's state lives. Unlike variables declared inside a function which disappear after...
Last updated on Dec 10, 2025
15 min read
ERC-20 Token on Starknet ERC-20 tokens on Starknet work the same way as on Ethereum. In fact, STRK (Starknet's fee token) is itself an ERC-20 token; there's no special "native" token at the protocol...
Last updated on Dec 10, 2025
6 min read
Solidity Coding Standards The purpose of this article is not to rehash the official Solidity Style Guide, which you should read. Rather, it is to document the common deviations from the style guide...
Last updated on Oct 29, 2025
The staking algorithm of SushiSwap MasterChef and Synthetix The MasterChef and Synthetix staking algorithms distribute a fixed reward pool among stakers according to their time-weighted contributions...
Last updated on Oct 29, 2025
12 min read
Interest Bearing Token Part 1 The Token-2022 interest-bearing extension enables a token mint to automatically accrue interest on all token accounts for that specific mint. It uses an annual rate...
Last updated on Oct 22, 2025
11 min read
Interest Bearing Token Part 2 The interest-bearing extension adds the ability for a token mint to accrue interest over time. In our previous discussion of Token-2022, we introduced the...
Last updated on Oct 22, 2025