git clean -x removes ignored files from the working tree; -n previews changes and -xdf deletes ignored files and directories, including local config files.

Rails select helpers can disable specific options by value, preventing choice of unavailable entries in forms.

Capybara and Cucumber can verify that a select box includes a disabled choice, using an XPath check on the matching option element.

exception_notification can send error reports as simple HTML emails instead of plain text, improving readability while still including a text-only fallback.

exception_notification 4.0.0+ adds options to filter crawler noise and ignore selected exceptions, keeping alerts actionable instead of a stream of routine failures.

RubyMine may report false syntax errors, and resetting the IDE settings can clear the issue.

Need a simple way to fake server replies during development when external APIs are unavailable or unreliable.

Calendars often turn work into a chain of interruptions, leaving little protected time for deep focus. Intentional scheduling can restore control over the day.

Record-level permission checks can be optimized by replacing scope lookups with a direct predicate, avoiding database ID scans for large collections.

Programmers lose more time to meetings because creative work needs long, uninterrupted blocks, while manager-style schedules fragment the day.

Ruby’s dollar-prefixed globals can make obscure code hard to read; knowing ARGV, process status, PID, and regex match variables helps decode them.

Ruby 1.9 adds a compact -> syntax for lambdas, making anonymous function definitions shorter while staying equivalent to lambda { |x| ... }.

ActionController::CookieJar looks like a Hash, but slice fails when selecting cookie subsets because Hash#slice instantiates the wrong class.

Generate bounded integers in Bash using $RANDOM; simple modulus limits the range, but it biases results toward lower values.

Selenium tests can fail with ActionView::Template::Error and a dump format error for a symbol, often caused by stale cached files in tmp/cache.

I switch to the new browser tab lets Selenium-enabled tests handle links that open a new tab or window, such as link_to(..., :target => '_blank').

On iPad in iOS 5, the onscreen keyboard can force position: fixed elements to behave like position: static, breaking forms and search fields.

In-place batch editing of many text files with plain Ruby can replace patterns across files without a separate script runner.

Memcached keys can be enumerated by querying slab statistics and dumping cached items, including AWS ElastiCache instances exposed on port 11211.

Removing a URL fragment without jumping the page avoids unwanted scrolling; assigning a dummy hash like window.location.hash = "_" keeps the view in place.

xmllint pretty-prints XML in the terminal and can write formatted output to a file, including gzipped XML inputs.

A friendly introduction to the web and HTTP’s purpose, using REST as a simple mental model for understanding request and response behavior.

Rails 4.0 is ready after betas and release candidates, bringing new features and removing older ones past their expiration date.