- Continuous integration: Frequent merging of several small changes into a main branch
- Continuous delivery: When teams produce software in short cycles with high speed and frequency so that reliable software can be released at any time, and with a simple and repeatable deployment process when deciding to deploy
- Continuous deployment: When new software functionality is rolled out completely automatically
CI/CD bridges the gaps between development and operation activities and teams by enforcing automation in building, testing and deployment of applications. CI/CD services compile the incremental code changes made by developers, then link and package them into software deliverables. Automated tests verify the software functionality, and automated deployment services deliver them to end users. The aim is to increase early defect discovery, increase productivity, and provide faster release cycles. The process contrasts with traditional methods where a collection of software updates were integrated into one large batch before deploying the newer version. Modern-day DevOps practices involve:
- continuous development,
- continuous testing,
- continuous integration,
- continuous deployment, and
- continuous monitoring
of software applications throughout its development life cycle. The CI/CD practice, or CI/CD pipeline, forms the backbone of modern day DevOps operations.
- Sacolick, Isaac (2020-01-17). "What is CI/CD? Continuous integration and continuous delivery explained". InfoWorld. Retrieved 2021-06-01.
- Rossel, Sander (October 2017). Continuous Integration, Delivery, and Deployment. Packt Publishing. ISBN 978-1-78728-661-0.
- Gallaba, Keheliya (2019). "Improving the Robustness and Efficiency of Continuous Integration and Deployment". 2019 IEEE International Conference on Software Maintenance and Evolution (ICSME): 619–623. doi:10.1109/ICSME.2019.00099. ISBN 978-1-7281-3094-1. S2CID 208879679.
- El Khalyly, B.; Belangour, A.; Banane, M.; Erraissi, A. (2020). "A new metamodel approach of CI/CD applied to Internet of Things Ecosystem". 2020 IEEE 2nd International Conference on Electronics, Control, Optimization and Computer Science (ICECOCS): 1–6. doi:10.1109/ICECOCS50124.2020.9314485. ISBN 978-1-7281-6921-7. S2CID 231645681.
- Sane, P. (2021). "A Brief Survey of Current Software Engineering Practices in Continuous Integration and Automated Accessibility Testing". 2021 Sixth International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET): 130–134. arXiv:2103.00097. doi:10.1109/WiSPNET51692.2021.9419464. ISBN 978-1-6654-4086-8. S2CID 232076320.