Design of an Intermediate Representation for Smart Contract Portability

Abstract

Ethereum and Hyperledger Fabric are architecturally heterogeneous‚ with Ethereum using the Ethereum Virtual Machine to execute Solidity contracts with order-execute transactions and pseudonymous ECDSA-based identity․ As Fabric runs Go chaincode under an execute-order-validate enforcement model‚ with MVCC conflict detection‚ X․509 certificate-based identity management‚ and an explicit key-value state API‚ smart contracts cannot be written to run on both Ethereum and Fabric without major duplication of effort‚ namely‚ maintaining two separate codebases‚ conducting two separate security audits‚ and manually re-implementing complex code․ This thesis aims to both design and test a Universal Intermediate Representation (UIR) for the migration of smart contract logic from Ethereum to Hyperledger Fabric in a structured, auditable and repeatable way. In the spirit of Design Science Research (DSR) (Peffers et al., 2007), this study investigates five portability barriers to the extent that they can be identified (PB-1 to PB-5) and relates them to six design requirements (R1 to R6). Based on this, two-stage prototype pipeline is created in Python, a front-end based on Solidity contracts and a back-end which generates Hyperledger Fabric Go chaincode. In three canonical case studies‚ SimpleStorage‚ Escrow and SimpleToken‚ we evaluated the translation with respect to four dimensions: feature translation rate‚ semantic approximation accuracy‚ barrier coverage and compilation success․ Out of the 14 categories of Solidity features‚ 6 (43%) are completely abstractable‚ 4 (29%) can be approximated with semantic gaps SG-1 to SG-2‚ and 4 (29%) are architecturally non-portable at the contract level․ All three Hyperledger Fabric Go chaincodes built using the UIR approach compiled successfully with go build‚ using Go version 1․22․5‚ showing the feasibility of the approach with Go․ The thesis is not about the fact that UIR is a production ready tool. The pipeline has no total automation; in the 3 case studies, the processing of function bodies was done manually in Stage 1. Also, the prototype currently only approximates 256-bit integers. The actual contribution is conceptual: It suggests a structured, auditable way to detect and overcome portability issues from Ethereum to Hyperledger Fabric. The master thesis consists of 94 pages; it contains 9 figures, 28 tables, 2 appendices, and 42 references.