Autocompleting Search Field

Goal

Provide a web service that gives autocomplete suggestions for the search bar. As the user starts typing a search query we should provide useful suggestions.

Possible sources of auto complete data:

• Previous searches
• Topics from public databases like Wikipedia, Freebase
• Previously visited links

Can we do advanced things like:

• Suggestions based on user's current geo location
• Keywords or hashtags from the user's social feeds
• Trending topics on social networks?

Performance

This should answer questions like:

• Can we lookup suggestions real-time?

Quality

This should answer questions like:

• Can we present the user with results that are relevant?

Infrastructure

This should answer questions like:

• Can we maintain a large index?
• How would be distribute the index?
• Can we easily update an index?
• Can we build a scalable infrastructure on the frontend that allows many clients?