"Caching is the answer" can't always be the answer. We discuss how to ensure your site is up-to-date when the data behind it is continuously changing.

We'll discuss three primary areas pertaining to real-time-data.

Where it comes from – real-time data sources

• Streaming APIs
• Polled APIs (and strategies for dealing with rate limits)
• PubSubHubbub

Data processing

• Denormalization
• Workers
• Incremental and generational MapReduce

Data presentation

• Partial caching
• Continuous caching
• Broadcasting real-time updates
• Failure models