EXHIBIT 99.1


     WIND RIVER COMPLETES ACQUISITION OF EMBEDDED SUPPORT TOOLS CORPORATION

         ALAMEDA, Calif., April 3, 2000 -- Wind River Systems, Inc.
(Nasdaq:WIND), a leader in embedded development software and services for the
Internet era, announced today that it has completed its acquisition of Embedded
Support Tools Corporation (EST). EST is a worldwide provider of integrated
hardware and software tools for programming, testing and debugging embedded
systems.

         Wind River issued an aggregate of 5,474,792 shares of its common stock
and reserved an additional 1,122,855 shares for issuance upon exercise of
outstanding employee stock options in exchange for all outstanding shares of EST
common stock, including shares issuable upon exercise of employee stock options.
The acquisition will be accounted for as a purchase. Based on Wind River's
average share price at the time the merger was announced, the transaction is
valued at approximately $327 million. The transaction is expected to be
accretive to earnings in the first full year of operations.

         "We expect the EST family of employees and technology to be a great fit
with the new Wind River," commented Tom St. Dennis, CEO of Wind River. "Our
customers increasingly need solutions that enable them to develop smart,
connected devices and get them to market quickly. By helping developers
accelerate porting, integrating and testing embedded systems with custom
hardware, EST's products and expertise provide a valuable competitive edge to
our customers."

         "Everyone here at EST is delighted to be joining Wind River at such an
exciting time," said Peter Dawson, president of EST. "With product complexity
growing almost daily, developers creating innovative, advanced applications must
increasingly focus on their core competencies to sustain competitive advantage.
Wind River is uniquely positioned to deliver solutions that enable companies to
build next-generation devices. We are very excited to be bringing our people and
technologies together to expand the depth and breadth of products at Wind River
and are confident that we will be an essential part of Wind River's growth and
success."

         Dawson will assume the position of vice president and general manager
of a new Wind River business unit focused on creating complete solutions
targeted at hardware / software integration. He and the other 150 EST employees
will operate out of EST's Canton, Massachusetts office.

ABOUT WIND RIVER

Wind River, www.windriver.com, is a worldwide leader in embedded software. Wind
River provides software development tools, real-time operating systems, and
advanced connectivity for use in products throughout the Internet,
telecommunications and data communications, digital imaging, networking,
medical, computer peripherals, automotive, industrial control and
aerospace/defense markets. Wind River is how smart things think. Founded in
1983, Wind River is headquartered in Alameda, California, with operations in
fifteen countries worldwide.




         THIS NEWS RELEASE CONTAINS FORWARD-LOOKING STATEMENTS THAT INVOLVE
RISKS AND UNCERTAINTIES THAT COULD CAUSE ACTUAL RESULTS OR OUTCOMES TO DIFFER
MATERIALLY FROM THOSE CONTEMPLATED BY THE FORWARD-LOOKING STATEMENTS. FACTORS
THAT COULD CAUSE OR CONTRIBUTE TO SUCH DIFFERENCES INCLUDE, BUT ARE NOT LIMITED
TO, THE RISKS INHERENT IN ACQUESTTIONS OF TECHNOLOGIES AND BUSINESSES, INCLUDING
THE INTEGRATION OF SEPARATE WORKFORCES, THE TIMING AND SUCCESSFUL COMPLETION OF
TECHNOLOGY AND PRODUCT DEVELOPMENT THROUGH PRODUCTION READINESS, INTEGRATION OF
SUCH TECHNOLOGIES AND BUSINESSES INTO WIND RIVER SYSTEMS, UNANTICIPATED
EXPENDITURES, CHANGING RELATIONSHIPS WITH CUSTOMERS, SUPPLIERS AND STRATEGIC
PARTNERS AND OTHER FACTORS DESCRIBED IN THE COMPANY'S MOST RECENT FORM 10-K AND
OTHER PERIODIC FILING WITH THE SECURITIES AND EXCHANGE COMMISSION.

CONTACT:          Pamela Sufi                      De Anna Mekwunye
                  Public Relations                 Investor Relations
                  Wind River                       Wind River
                  510-749-2340                     510-749-2577
                  PAMELA.SUFI@WINDRIVER.COM        deanna.mekwunye@windriver.com

         Wind River Systems and the Wind River Systems logo registered
trademarks of Wind River Systems, Inc. Tornado is a trademark of Wind River
Systems, Inc. Other names are registered trademarks or trademarks of the
respective companies or organizations.


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