Bitcoin v0.3 was released on SourceForge on July 6, 2010, five days before the Slashdot posting that would bring Bitcoin its first surge of new users.
What’s new in v0.3:
- Command line and JSON-RPC control
- Includes a daemon version without GUI
- Transaction filter tabs
- 20% faster hashing
- Hashmeter performance display
- Mac OS X version (thanks to Laszlo)
- German, Dutch and Italian translations (thanks to DataWraith, Xunie and Joozero)
The JSON-RPC interface and daemon mode were particularly significant technical additions, enabling Bitcoin to be run as a background service and controlled programmatically. This laid the groundwork for exchanges, payment processors, and other services to integrate Bitcoin.
The wallet design entry traces the capability back further: JSON-RPC first appeared on SVN as v0.2.6 in February 2010, five months before this release made it a headline feature.
The Mac OS X port was contributed by Laszlo Hanyecz, who had become famous just weeks earlier on May 22, 2010 for making the first known real-world Bitcoin purchase — buying two pizzas for 10,000 BTC. The port is documented in more detail in Hanyecz’s biography. Hanyecz later recalled his correspondence with Satoshi from this period.
The Slashdot article published five days after this release with the headline “Bitcoin Releases Version 0.3” brought an enormous surge of interest. According to the Bitcoin Wiki’s history page, the exchange price rose from about $0.008 to $0.08 over the five days from July 12, as thousands of new users discovered the project. Writing to Martti Malmi on July 18, Satoshi called it “the slashdot flood of work”.
