  With the recent popularity of Blockchain and other Distributed Ledger
Technologies (DLT), blockchain enabled smart contract applications has
attracted increased research focus. However, the immutability of the blocks,
where the smart contracts are stored, causes conflicts with the traditional
Software Development Life Cycle (SDLC) models usually followed by software
engineers. This clearly shows the unsuitability of the application of SDLC in
designing blockchain enabled smart contract based applications. This research
article addresses this current problem by first exploring the six traditional
SDLC models, clearly identifying the conflicts in a table with the application
of smart contracts and advocates that there is an urgent need to develop new
standard model(s) to address the arising issues. The concept of both block
immutability and contract is introduced. This is further set in a historical
context from legacy smart contracts and blockchain enabled smart contracts
extending to the difference between "shallow smart contracts" and "deep smart
contracts". To conclude, the traditional SDLC models are unsuitable for
blockchain enabled smart contract-based applications.
