Mathias Paulenko

Identify missing, unused, and inefficient indexes by reading execution plans and measuring query cost with EXPLAIN.

Rename columns or change data types without locking tables by using views, triggers, and backfill strategies.

Split huge SQL tables into smaller partitions by date, range, or list to improve query performance and maintenance.

Query tree-like or graph-like structures in SQL using recursive common table expressions to walk parent-child relationships.

Use SQL window functions to rank rows, compute running totals, and compare values within partitions without self-joins.

Automate AWS resource provisioning, tagging, and cleanup using Bash scripts wrapped around the AWS CLI.

Automate file backups with retention policies using a Bash script that rotates daily, weekly, and monthly snapshots.

Set up basic firewall rules using iptables in Bash to filter traffic, block ports, and protect Linux servers.

Rotate and compress application logs with Bash to prevent disk exhaustion and simplify log retention.

Alert when disk space crosses thresholds using a Bash script that checks mount points and notifies operators.

Run shell commands and scripts in parallel safely using xargs, parallel, or background jobs with concurrency control.

Generate, rotate, and distribute SSH keys securely with Bash scripts for team and server access.

Choose between synchronous and asynchronous communication patterns for resilient microservices architectures.

Combine workloads into fewer compute resources to reduce cost, improve utilization, and simplify operations.

Centralize application configuration outside of deployment artifacts to support live updates and multi-environment management.

Route requests to multiple backend services through a single entry point that handles cross-cutting concerns.

Expose lightweight health endpoints so orchestrators, load balancers, and monitoring tools can verify service availability.

Coordinate a single active instance among multiple distributed nodes to avoid conflicts and split-brain scenarios.

A template for auditing user access rights, verifying least privilege, and documenting access decisions across systems and teams.

A template to plan and document backup verification tests, ensuring restore procedures work before an emergency.

A template for securing build and deployment pipelines against credential leaks, tampering, supply chain attacks, and unauthorized...

A policy template for enforcing consistent labels on cloud resources to improve cost allocation, security, and operations.

A template for mapping current security controls to compliance frameworks like SOC 2, ISO 27001, and PCI-DSS.

A baseline template for hardening container images, runtimes, and orchestration configurations across environments.