CI/CD Explained: What Really Happens After You Merge a Pull Request

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A developer education series on DEV Community uses a fictional senior-junior engineer dialogue to explain how code moves from a merged pull request to production. The first episode opens with a cautionary tale of a developer SSHing directly into a production server on a Friday evening to push a quick fix. The story is used to contrast deployment practices across different company types, from small startups using manual SSH access to banks with fully audited, pipeline-driven processes. Key concepts introduced include why process managers like PM2 are used instead of running Node.js directly, and the difference between npm install and npm ci. The series aims to build conceptual understanding of CI/CD systems, pipelines, and deployment strategies rather than focusing on syntax.

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One design-doc question that prevents Azure APIM naming collisions in CI/CD pipelines

A CI/CD pipeline failure in Azure API Management (APIM) was traced to a naming collision between a manually created named value and one deployed via an automated publisher, both sharing the same display name but different system IDs. APIM enforces uniqueness on the human-facing 'name' field rather than the system-assigned 'id', a distinction that is rarely documented during design reviews. The incident went undetected for months because the conflicting resource had been created through the portal by a different team member, with no platform-level warning issued to either party. The author argues that design documents should explicitly state which identifier field is unique, at what scope, and what happens on collision — a one- or two-sentence addition that forces authors to verify enforcement rules before shipping. Restricting manual portal access was considered but rejected as the wrong fix; the real gap is undocumented compound identity, not the creation method itself.

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ProgrammingDEV Community ·

Silent CI gate passed for weeks without checking a single file

A Python-based CI lint check was silently reporting success for weeks without executing any assertions, because the test pod it ran on lacked a git binary. When subprocess.run called git ls-files and received a FileNotFoundError, the process crashed before any file was checked, yet the CI gate marked the run as green. The root cause was a missing fallback: without git, the file enumerator returned zero files, and zero-files-checked looked identical to all-files-passed. The team fixed this by adding an os.walk fallback for environments without git and a hard failure when the enumerator returns an empty file list. The incident highlights a broader CI risk: a check that crashes before asserting is more dangerous than no check at all, because it creates a false sense of coverage.

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ProgrammingDEV Community ·

7 Skills DevOps Engineers Need to Stay Relevant as AI Handles Routine Tasks

As AI tools grow capable of writing infrastructure code, generating Dockerfiles, and drafting CI/CD pipelines, many are questioning whether DevOps engineers face obsolescence. Experts argue AI will automate repetitive tasks but cannot replace engineers who understand complex systems, diagnose production failures, and make high-stakes decisions. The most in-demand DevOps professionals in 2026 are expected to combine core technical knowledge with AI-assisted productivity. Key skills highlighted include Kubernetes, Terraform, Linux administration, Docker, Git, and cloud platform fundamentals. Rather than competing with AI, engineers are advised to deepen their understanding of why systems work, not just how to operate them.

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ProgrammingDEV Community ·

12 AWS Networking Interview Questions and What Interviewers Really Want to Hear

A seasoned interviewer who has conducted around 40 AWS-focused technical interviews shares the 12 most common networking questions and the reasoning behind each. Data from 1,393 interview sessions on LastRound AI between January 2025 and July 2026 shows DevOps Engineering roles attracted more candidates than backend, frontend, and full-stack combined, raising the competitive bar. Many candidates fail not because the questions are difficult, but because they recite definitions instead of demonstrating diagnostic thinking. Key topics include VPC CIDR planning, the difference between public and private subnets, stateful security groups versus stateless NACLs, and systematically troubleshooting why an EC2 instance cannot reach the internet. The article emphasizes that strong candidates walk through problems as a logical chain rather than naming a single cause and stopping.

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