Profile – PubSub

Company: PubSub

Location: New York

Launched: February 9, 2004

What is it?

PubSub, which is short for “publish and subscribe”, is a future search engine. It’s also called “persistent search”. Users input keywords on subjects that they are interested in. The keywords are stored, or “persistent”. PubSub’s matching engine compares these stored/persistent queries against newly-discovered pages on an ongoing basis, in real time.

What this means: If you would like to be notified of websites that post about subjects you are interested in, you input the search terms, and PubSub will notifiy you as posts appear that include your keywords. A great (necessary, really) feature is the ability to store any persistent search and view it via RSS in your favorite reader. At TechCrunch, for instance, we have stored search terms like “Web 2.0” and are notified in our RSS reader of all new posts or articles that include the term “Web 2.0”.

People generally refer to what PubSub does as either persistent search or future search, whereas regular search engines like Google are refered to as retrospective search. Persistent search notifies you of future content as it is created. Retrospective search engines help you find content that is already out there on the web.

If you find it hard to get your mind around this, try it out, and make sure you take the RSS feed from your subscription so that you don’t have to go back to the site to check and see if there are any new results. As the alerts start rolling in to your RSS reader, you will be very pleasantly surprised.

PubSub is also very strongly behind a structured blogging initiative which helps bloggers structure topic-specific posts like reviews (books, music, etc.) and events. A wordpress plugin is available at, that we use here at TechCrunch as well as on our personal blogs.

We like pubsub and have many, many subscriptions to keep us up to date on topics that interest us. As an example, here is the RSS feed for our subscription to “web2.0 and web 2.0” (where we seem to consistently find great posts from a blog called the Read/Write Web, the second best Web 2.0 blog on the net :-).

Key Features:

– Future or Persistent search at lightning-fast speeds (subject only to RSS time limitations)
– web based
– IE or Firefox client option – see screen shot #3
– Great user interfact

Screen Shots:


Bob Wyman, CTO and co-founder
Salim Ismail, CEO and co-founder
Richard Treadway, CMO

Relevant Links:

media coverage
about pubsub
Bob Wyman’s Blog
John Battelle on PubSub
Charlene Li on Pubsub