Alex Kumar

Production visibility requires more than basic request logging. I instrument critical code paths using ActiveSupport::Notifications to publish custom metrics that monitoring services consume. Each instrumented block publishes events with timing data,

ActiveJob provides a unified interface across different queue backends (Sidekiq, Resque, Delayed Job), making it easier to switch adapters or test jobs. I define jobs by inheriting from ApplicationJob and implementing perform. ActiveJob handles serial

Complex reporting queries with multiple joins and aggregations can become unmaintainable in ActiveRecord. PostgreSQL views encapsulate query complexity in the database layer and appear as regular tables to Rails. I create views for common reporting ne

Long-running requests tie up worker threads and degrade overall application responsiveness. Rack::Timeout enforces request timeouts at the Rack layer, killing requests that exceed configured limits. I set conservative timeouts (15-30 seconds) and hand

While JWT works well for user authentication, service-to-service communication often uses simpler API key authentication. I generate cryptographically random API keys using SecureRandom.hex(32) and store them hashed in the database, similar to passwor

Understanding query execution plans is essential for optimizing slow queries. Rails provides explain method on ActiveRecord relations to show PostgreSQL's query planner output. I look for sequential scans on large tables (indicating missing indexes),

ActiveStorage provides a unified interface for uploading files to cloud storage services like S3, GCS, or Azure Storage. I configure storage services in config/storage.yml and attach files to models using has_one_attached or has_many_attached macros.

ETags enable efficient caching by allowing clients to make conditional requests that return 304 Not Modified when content hasn't changed. Rails automatically generates ETags based on response content, and fresh_when or stale? methods handle the condit

Recurring tasks like cleanup jobs, report generation, or cache warming need reliable scheduling. The sidekiq-scheduler gem extends Sidekiq with cron-like scheduling without requiring separate infrastructure like cron or Kubernetes CronJobs. I define s

Password reset workflows require careful security design to prevent account takeover. I generate time-limited, single-use tokens using Rails' signed_id feature which creates tamper-proof tokens without database storage. The token expires after a short

SaaS applications serving multiple customers (tenants) need data isolation to prevent cross-tenant data leaks. The apartment gem provides schema-based multi-tenancy for PostgreSQL where each tenant gets a separate schema, ensuring complete database-le

Large JSON payloads consume bandwidth and increase latency, especially for mobile clients on slow connections. Rack::Deflater middleware automatically compresses responses using gzip when clients send Accept-Encoding: gzip headers. This typically redu