Redis Sentinel: How Automatic Failover Actually Works
How Redis Sentinel provides high availability: quorum-based monitoring, master election, automatic failover, and what your client applications must do to follow along.
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Inspecting Sidekiq Jobs from the Rails Console
Console-ready Ruby snippets to inspect Sidekiq queues, scheduled jobs, retry and dead sets, and currently running workers when the dashboard is not enough.
Rails N+1 Queries: joins vs preload vs eager_load vs includes
What joins, preload, eager_load, and includes actually do in ActiveRecord, shown with real SQL logs, plus the chained calls that quietly bring the N+1 back.
Production Debugging Techniques for Rails Apps
Practical production debugging techniques for Rails: log analysis, replicating production data, rbtrace live injection, feature-flagged debug modes, and replica apps.
A .irbrc Full of Ruby Debugging and Introspection Helpers
A collection of .irbrc helpers for tracing method calls, logging SQL queries, profiling code, and inspecting Ruby objects during Rails console debugging.
Rails Session Stores: Cookie, ActiveRecord, and Redis
A comparison of Rails session stores: cookie sessions, ActiveRecord, and Redis, including how to share sessions across subdomains and multiple apps.
Rails Secrets: Credentials, 1Password, and Cloud Vaults
A rundown of Rails credentials, environment variables, 1Password CLI, and cloud secret managers like AWS Secrets Manager and Vault, and when to use each.
Config Approaches: Files, Env Vars, and Config Servers
A comparison of YAML config files, Rails encrypted credentials, environment variables, and centralized config servers, with the trade-offs of each approach.
How to Set a Breakpoint on Devise's current_user Method
Why byebug can't break on Devise's metaprogrammed current_user method, and several ways to debug or patch a method that isn't in your source.
Fragment Caching a Large List That Changes Constantly
How splitting static and dynamic fields, granular fragment caching, and incremental loading keep a large, frequently updated list fast without stale data.