Anti-patterns in Infrastructure as Code

Defects in infrastructure as code (IaC) scripts can have serious consequences for organizations who adopt DevOps. By identifying which characteristics of IaC scripts correlate with defects, we can identify anti-patterns, and help software practitioners make informed decisions on better development and maintenance of IaC scripts, and increase quality of IaC scripts. The goal of this paper is to help practitioners increase the quality of IaC scripts by identifying characteristics of IaC scripts and IaC development process that correlate with defects, and violate security and privacy objectives. We focus on characteristics of IaC scripts and IaC development that (i) correlate with IaC defects, and (ii) violate security and privacy-related objectives namely, confidentiality, availability, and integrity. For our initial studies, we mined open source version control systems from 3 organizations: Mozilla, Openstack, and Wikimedia, to identify the defect-related characteristics and conduct our case studies. From our empirical analysis, we identify (i) 14 IaC code and four churn characteristics that correlate with defects; and (ii) 12 process characteristics such as, frequency of changes, and ownership of IaC scripts that correlate with defects. We propose the following studies: (i) identify structural characteristics that correlate with defect; (ii) with respect to prediction performance, compare which characteristics of IaC scripts are more correlated with defects; and (iii) identify characteristics that violate security and privacy objectives.