Summary

While reviewing the provided Solidity source files (e.g., IAlchemist.sol, ITransmuter.sol, IVelo.sol), I noticed that they are missing an SPDX-License-Identifier at the beginning of the files. The SPDX identifier is important to clearly specify the licensing terms of the code, ensuring clarity on its usage and distribution.

Vulnerability Details

The issue lies in the absence of an SPDX-License-Identifier at the top of the Solidity files. This identifier is used to declare the licensing terms under which the code is shared. It is a best practice to add it, especially when publishing or sharing the code in public repositories or collaborative projects.

The absence of the SPDX-License-Identifier can result in a lack of clarity regarding the licensing and could potentially confuse users and contributors regarding the usage rights of the code.

Impact

Although this does not impact the functionality or security of the contract, it can lead to challenges in understanding the licensing terms of the code. It could be flagged by platforms like GitHub if the code is shared publicly, and may cause compliance issues for contributors who wish to use or modify the code.

Tools Used

• Manual code review

• Solc (Solidity compiler) for SPDX warnings

Recommendations

I recommend adding the appropriate SPDX-License-Identifier at the top of each Solidity file. For example: