A Pruneable Approach for Bazo

Bazo (Esperanto for „base" or „foundation") is a cryptocurrency created by the University
of Zürich for an external _nancial entity that facilitates the use of a customer bonus points program. Every purchase made by a customer allows him to collect points that can be spent with registered partners. The objective of the Bazo blockchain is to replace the need of having a bespoke contract for each of these partners by replacing the
procedure with a decentralized system. The system also allows customers to perform direct payments to partners and other customers without the need of supervised and
ine_cient administrative procedures. Bazo was created with simplicity and scalability in mind since the beginning, however it faces the same limitations of many existing
blockchains, namely scalability, speed and e_ciency. Scalability and speed are being tackled by other students.
Storage space is also a limitation commonly faced by blockchains since there is a need to fetch and store all blocks and transaction ever created in order to validate new blocks.
The goal of the thesis is to propose a solution for the storage problem by creating a snapshot of the system in a way that older blocks are no longer needed and can be safely
discarded/pruned.