EMPLOYEE OFFER LETTER

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                                                                   Exhibit 10.30

April 12, 2005

Cathy Welsh
[address]

Dear Cathy:

On behalf of Akamai Technologies, Inc. (referred to in this letter collectively
with its subsidiaries as the "Company"), I am pleased to confirm the offer of
full-time employment with the Company that Paul Sagan made to you for the
position of Chief Human Resources Officer in our Cambridge office. You will
report to Paul in this capacity starting on April 29, 2005. This offer is
contingent upon the following: (1) completion of an employment application,
which is enclosed with this letter; (2) your consent to and the successful
completion of a background investigation conducted pursuant to the Company's
standard procedures.

Your base salary will be $8,076.92 bi-weekly ($210,000.00 on an annualized
basis). You will be eligible to receive an annual incentive bonus, based on
performance against objectives set by your manager, of 25% of your base salary
(pro-rated for 2005). Your compensation shall be subject to review annually.

As part of this employment offer, the Company will recommend to the Akamai Board
of Directors that you be granted a stock option under the Company's 1998 Stock
Incentive Plan (the Plan) for the purchase of an aggregate of 65,000 shares of
Common Stock of the Company, at an option price equal to the fair market value
of the Common Stock as determined by the Board on the date the Board of
Directors approves your stock option. If approved, your stock options at Akamai
will vest over four years, provided you remain employed, all on a schedule
beginning on the date your options are granted. The first 25 percent of the
options will vest on the first anniversary of your Grant Date. An additional
6.25% of the original number of shares will vest at the end of each successive
full three-month period following the first anniversary of the Grant Date until
the fourth anniversary of the Grant Date. Subject to Board approval, your
options will be evidenced by a separate option agreement embodying these terms.
You will also be eligible to receive such future stock option grants, as the
Board of Directors shall from time to time deem appropriate.

You will be eligible to participate in the Employee Stock Purchase Program
beginning in the June 2005 offering period. This plan allows you to contribute
between 1% and 15% of your salary through regular payroll deductions. The Akamai
plan provides for a two-year offering period, that includes four, six-month
purchase periods. At the end of each six-month purchase period, the money that
has been deducted will be used to purchase shares of Akamai common stock at 85%
of the closing price of the Common Stock at the beginning of the offer period or
end of the purchase period, whichever is lower.

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You will be eligible to elect health insu