  Blockchain applications are witnessing rapid evolution, necessitating the
integration of upgradeable smart contracts. Software patterns have been
proposed to summarize upgradeable smart contract best practices. However,
research is missing on the comparison of these upgradeable smart contract
patterns, especially regarding gas costs related to deployment and execution.
This study aims to provide an in-depth analysis of gas costs associated with
two prevalent upgradeable smart contract patterns: the Proxy and diamond
patterns. The Proxy pattern utilizes a Proxy pointing to a logic contract,
while the diamond pattern enables a Proxy to point to multiple logic contracts.
We conduct a comparative analysis of gas costs for both patterns in contrast to
a traditional non-upgradeable smart contract. We derive from this analysis a
theoretical contribution in the form of two consolidated blockchain patterns
and a corresponding decision model. By so doing we hope to contribute to the
broader understanding of upgradeable smart contract patterns.
