TLS certificates encrypt traffic between clients and servers. Let's Encrypt provides free, automated certificates via the ACME protocol. In Kubernetes, cert-manager automates certificate issuance and renewal. A ClusterIssuer configures the ACME server

AWS IAM (Identity and Access Management) controls access to cloud resources. Policies are JSON documents with Effect, Action, and Resource fields. The principle of least privilege grants only required permissions. Allow permits actions, Deny always ov

Structured logging outputs JSON-formatted log entries for machine parsing. Each log line includes timestamp, level, message, and contextual fields like request_id, user_id, and service. Structured logs enable powerful queries in Elasticsearch through

Grafana visualizes Prometheus metrics through configurable dashboards. Dashboard JSON models define panels, queries, and layouts programmatically. Panel types include timeseries for graphs, stat for single values, table for tabular data, and gauge for

Prometheus collects and stores time-series metrics via a pull model. It scrapes /metrics endpoints at configured intervals. The prometheus.yml defines scrape_configs with target discovery. static_configs list fixed targets while kubernetes_sd_configs

Nginx serves as a high-performance reverse proxy and load balancer. The upstream block defines backend server pools. Load balancing methods include round-robin (default), least_conn, ip_hash, and random. The proxy_pass directive forwards requests to u

Shell scripts automate repetitive DevOps tasks like deployments, backups, and health checks. I use #!/bin/bash with set -euo pipefail for strict error handling—-e exits on error, -u errors on undefined variables, -o pipefail catches pipe failures. Fun

Terraform provisions managed database services declaratively. AWS RDS supports PostgreSQL, MySQL, and other engines with aws_db_instance. The engine_version pins database versions. instance_class sets compute size. allocated_storage and max_allocated_

Terraform modules encapsulate related resources into reusable, composable packages. A module is simply a directory with .tf files. The root module calls child modules with the module block. Input variable blocks parameterize modules. output blocks exp

Terraform is an infrastructure as code (IaC) tool that provisions cloud resources declaratively. Configuration files use HCL (HashiCorp Configuration Language). The provider block configures cloud providers like AWS, GCP, or Azure. resource blocks def

GitLab CI/CD uses .gitlab-ci.yml for pipeline configuration. Pipelines consist of stages that run sequentially. Jobs within the same stage run in parallel. The image key sets the Docker image for each job. variables define global or job-level environm

GitHub Actions automates build, test, and deploy workflows. Workflows are defined in .github/workflows/ YAML files. The on key specifies triggers—push, pull_request, schedule, or workflow_dispatch. Jobs run on runners with configurable OS. steps execu