One of the key benefits of blockchain technology is its ability to keep a permanent, unalterable record of transactions. In business environments, where companies interact with each other without a centralized authority to ensure trust between them, this has led to blockchain platforms and smart contracts being proposed as a means of implementing trustworthy collaborative processes. Software engineers must deal with them to ensure the quality of smart contracts in all phases of the smart contract lifecycle, from requirements specifications to design and deployment. This broad scope and criticality of smart contracts in business environments means that they have to be expressed in a language that is intuitive, easy-to-use, independent of the blockchain platform employed, and oriented towards software quality assurance. In this paper we present a key component: a first outline of a UML-based smart contract meta-model that would allow us to achieve these objectives. This meta-model will be enriched in future work to represent blockchain environments and automated testing.

Blockchain technology is a chain of cryptographically linked blocks. It was designed to be immutable, so that the identity and traceability of the information entered would be guaranteed. After analyzing several traceability solutions, in the context of a Spanish company project, it was found that in order for a traceability solution to be efficient and agile, an additional layer is necessary in the blockchain. Since this need originated in the industrial sector, the subject has awakened considerable interest in the research community. This paper explains why the extra layer is essential and why it should ideally be totally independent of the information that is recorded on the blockchain network. Although data in a blockchain network is immutable, the paper also outlines the need for additional verification mechanisms capable of determining whether the raw data was correct. Finally, it includes planned future work.

The use of smart contract augurs a world without intermediaries because the code and the agreements contained therein exist across a distributed, decentralized blockchain network. In software engineering, this collaboration is usually represented by using business process models and smart contracts can be used to implement business collaborations in general and inter-organizational business processes. The validation of this contract and the assurance of its quality are critical for its right application. Early testing in smart contract definition is the fact of this paper. The paper discusses the possibility to use transformation protocols to obtain derived artefacts like test case definitions and smart contract code scaffolds. Generation of derived artefacts significantly reduces the number of defects before deploying the smart contract code in the blockchain network. Transformations protocols are created using model-based software development and modelling techniques. This approach allows to simplify and improve the management and execution of collaborative business processes. This would allow, in addition, the application of systematic mechanisms to evaluate and validate the smart contract and, particularly, the application of early testing techniques which would help to reduce the number of defects and, ultimately, the cost of the final review.

Immutability - the ability for a Blockchain (BC) Ledger to remain an unalterable, permanent and indelible \nhistory of transactions - is a feature that is highlighted as a key benefit of BC. This ability is very important \nwhen several companies work collaboratively to achieve common objectives. This collaboration is usually \nrepresented by using business process models. BC is considered as a suitable technology to reduce the \ncomplexity of designing these collaborative processes using Smart Contracts. This paper discusses how to \ncombine Model-based Software Development, modelling techniques, such as use cases models and activity \ndiagram models based on Unified Model Languages (UML) in order to simplify and improve the modelling, \nmanagement and execution of collaborative business processes between multiple companies in the BC \nnetwork. This paper includes the neccessity of using transformation protocols to obtain Smart Contract code. \nIn addition, it presents systematic mechanisms to evaluate and validate Smart Contract, applying early testing \ntechniques, before deploying the Smart Contract code in the BC network.