EXHIBIT 10.13 EMPLOYMENT AGREEMENT

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                                                                   EXHIBIT 10.13

                              EMPLOYMENT AGREEMENT

          This Agreement, dated as of November 23, 2005, is entered into by and
between William C. Stone (the "Executive") and Sunshine Acquisition Corporation,
a Delaware corporation (together with any successor thereto, the "Company").

                                 WITNESSETH THAT

          WHEREAS, the Company, Sunshine Merger Corporation and SS&C
Technologies, Inc. ("SS&C") entered into an Agreement and Plan of Merger dated
July 28, 2005 (the "Merger Agreement"); and

          WHEREAS, subject to the consummation of the Merger as described in the
Merger Agreement, the Company and the Executive wish to set forth the terms and
conditions of Executive's employment with the Company and SS&C in a binding
written agreement.

          NOW, THEREFORE, in consideration of the mutual covenants set forth in
this Agreement, it is hereby agreed as follows:

          1. Term of Employment. The term of the Executive's employment under
this Agreement (the "Term") shall begin on the Effective Date of the Merger, as
defined in the Merger Agreement (the "Effective Date") and end on the third
anniversary thereof; provided, that the Term shall be extended by successive
periods of one (1) year, unless the Company shall have notified the Executive or
the Executive shall have notified the Company that no such extension shall take
place, in each case at least ninety (90) days prior to the expiration of the
then-current Term (a "Notice of Nonrenewal"); and provided, further, that the
Term shall in any event end upon a termination of employment in accordance with
the terms of Section 5 hereof.

          2. Position, Duties and Location.

          (a) Position. Beginning on the Effective Date, the Executive shall
serve as Chairman of the Board of Directors of the Company (the Board") and
Chief Executive Officer of the Company and SS&C, with the duties and
responsibilities customarily assigned to those positions consistent with past
practice and such other duties and responsibilities as the Board of Directors of
the Company (the "Board") shall from time to time reasonably assign to the
Executive consistent with Executive's position. The Executive shall at all times
report directly to the Board. In addition, Executive shall serve as the Chairman
of the Board of Directors of SS&C and any direct or indirect parent or holding
company, the assets of which are the stock of SS&C.

          (b) Duties. During the Term, the Executive shall devote Executive's
full business attention and time to the business of the Company and SS&C and
shall use Executive's reasonable best efforts to carry out such responsibilities
faithfully and efficiently. During the Term, it shall not be considered a
violation of the foregoing for the Executive to serve on

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corporate, civic or charitable boards or committees, and manage personal
investments, so long as such activities do not materially interfere with the
performance of the Executive's responsibilities as an employee of the Company
and SS&C and do not violate the restrictions contained in Section 7.

          (c) Location. The Executive's services shall be performed primarily at
SS&C's offices in Windsor, Connecticut.

          3. Compensation.

          (a) Base Salary. During the Term, the Executive shall receive a base
salary (the "Base Salary") at an annual rate of not less than five-hundred
thousand dollars ($500,000), payable at such times as SS&C customarily pays the
base salaries of other senior executives of SS&C (hereinafter, "Other Senior
Executives"). The Base Salary shall be reviewed annually for increase in
accordance with SS&C's normal practices for Other Senior Executives. The Base
Salary shall not be reduced, including, after any increase, and the term "Base
Salary" shall thereafter refer to the Base Salary as so increased.

          (b) Annual Bonus. During the Term, the Executive shall be eligible to
earn an annual bonus (the "Annual Bonus") based on individual and Company
performance goals mutually determined by Executive and the Board. The Board
shall set Executive's target Annual Bonus each year (the "Target Annual Bonus").
Subject to Executive remaining employed by the Company through December 31st of
the applicable calendar year, Executive will receive a minimum Annual Bonus of
$450,000; provided, that for calendar year 2005, Executive's minimum Annual
Bonus of $450,000 shall be pro-rated for the time period beginning on the
Effective Date and ending on December 31, 2005.

          (c) Long Term Incentive Compensation.

               (i) During the Term and subject to the terms of this Agreement,
Executive shall be eligible to receive annual awards under any long term
incentive program or similar plan, program or arrangement of the Company, which
may include options to purchase shares of common stock of the Company
("Options") or restricted shares of common stock of the Company ("Restricted
Shares").

               (ii) Notwithstanding the generality of the foregoing clause (i),
on or at the first Board meeting following the Effective Date, Executive shall
be granted an option to purchase that number of shares of common stock of the
Company equal to 2% of the fully diluted shares of the Company, as determined
immediately following the Effective Date (the "Initial Option"), at a per share
exercise price equal to the per share price paid by Carlyle Partners IV, L.P. to
purchase shares of common stock of the Company on the Effective Date. Subject to
the terms of Section 5 hereof, the Initial Option shall vest based on the
passage of time and/or the achievement of performance milestones as provided in
the option program that will be approved by the Board on or at the first Board
meeting following the Effective Date.

               (iii) All Options granted to Executive shall (A) have a per share
exercise price that is no greater than fair market value of a share of common
stock of the


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Company on the date of grant; (B) have a maximum term of ten years from the date
of grant; and (C) otherwise be subject to the terms of this Agreement.

               (iv) Subject to Section 5 of this Agreement, the Company, SS&C
and the Executive agree that Executive's stock options to purchase SS&C common
stock that are assumed by the Company in the Merger (the "Assumed Options")
shall continue to vest in accordance with their terms, as adjusted to reflect
the shares of Company common stock issued in the Merger, notwithstanding any
contrary action taken by the Board of Directors of SS&C prior to the Merger.

          4. Other Benefits.

          (a) Benefits. During the Term, the Executive shall be entitled to
participate in the benefits, incentive and compensation plans programs and
arrangements of SS&C ("Employee Benefit Plans"), on terms and conditions no less
favorable than those applicable to any Other Senior Executive. Without limiting
the generality of the foregoing, Executive shall be entitled to no less than six
(6) weeks of paid vacation per calendar year.

          (b) Perquisites. The Board may from time to time approve the granting
of additional benefits to Executive including, but not limited to, life and/or
disability insurance, car allowance or Company car, or membership in health,
business or social and/or other clubs, associations or organizations. Such
perquisites shall be no less favorable in any material respect than such
perquisites provided to the Executive by SS&C prior to the Merger.

          (c) Expenses. During the Term, the Executive shall be entitled to
receive prompt reimbursement for all reasonable expenses that Executive incurs
during the Term in carrying out Executive's duties under this Agreement.

          (d) Key Person Insurance. The Company and SS&C shall have the right to
insure the life of the Executive for the Company's and/or SS&C's sole benefit.
The Company and SS&C shall have the right to determine the amount of insurance
and the type of policy. The Executive shall cooperate with the Company and SS&C
in obtaining such insurance by submitting to reasonably required physical
examinations, by supplying all information reasonably required by any insurance
carrier, and by executing all necessary documents reasonably required by any
insurance carrier. The Executive shall incur no financial obligation by
executing any required document, and shall have no interest in any such policy.

          (e) Indemnity. The Company and SS&C agree that if the Executive is
made a party, or is threatened to be made a party, to any action, suit or
proceeding, whether civil, criminal, administrative or investigative (a
"Proceeding"), by reason of the fact that Executive is or was a director,
officer or employee of the Company or SS&C or is or was serving at the request
of the Company or SS&C as a director, officer, member, employee or agent of
another corporation, partnership, joint venture, trust, limited liability
company or other enterprise, including service with respect to employee benefit
plans, whether or not the basis of such Proceeding is the Executive's alleged
action in an official capacity while serving as a director, officer, member,
employee or agent, the Executive shall be indemnified and held harmless by the
Company and SS&C to the fullest extent legally permitted or authorized by the
Company's and


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SS&C's certificates of incorporation or bylaws or resolutions of the Board or,
if greater, by the laws of the State of Delaware, against all cost, expense,
liability and loss (including, without limitation, attorney's fees, judgments,
fines, ERISA excise taxes or other liabilities or penalties and amounts paid or
to be paid in settlement) reasonably incurred or suffered by the Executive in
connection therewith, and such indemnification shall continue as to the
Executive even if Executive has ceased to be a director, member, employee or
agent of the Company, SS&C or other entity and shall inure to the benefit of the
Executive's heirs, executors and administrators. To the extent permitted by
applicable law, the Company and SS&C shall advance to the Executive all
reasonable costs and expenses incurred by Executive in connection with a
Proceeding within twenty (20) calendar days after receipt by the Company of a
written request for such advance. Such request shall include an undertaking by
the Executive to repay the amount of such advance if it shall ultimately be
determined that Executive is not entitled to be indemnified against such costs
and expense. Neither the failure of the Company nor SS&C (including their boards
of directors, independent legal counsel or stockholders) to have made a
determination prior to the commencement of any proceeding concerning payment of
amounts claimed by the Executive that indemnification of the Executive is proper
because Executive has met the applicable standard of conduct, nor a
determination by the Company or SS&C (including its board of directors,
independent legal counsel or stockholders) that the Executive has not met such
applicable standard of conduct, shall create a presumption that the Executive
has not met the applicable standard of conduct. The Company and SS&C agree to
continue and maintain a directors' and officers' liability insurance policy
covering the Executive to the extent the Company and SS&C provide such coverage
for their other executive officers. Such insurance coverage shall be maintained
for at least six (6) years following any Change in Control.

          (f) Section 409A. To the extent that the Company reasonably determines
that any compensation or benefits payable under this Agreement are subject to
Section 409A of the Internal Revenue Code of 1986, as amended (the "Code"), this
Agreement shall incorporate the terms and conditions required by Section 409A of
the Code and Department of Treasury regulations as reasonably determined by the
Company and the Executive. To the extent applicable, this Agreement shall be
interpreted in accordance with Section 409A of the Code and Department of
Treasury regulations and other interpretative guidance issued thereunder,
including without limitation any such regulations or other such guidance that
may be issued after the Effective Date. Notwithstanding any provision of this
Agreement to the contrary, in the event that following the Effective Date the
Company reasonably determines that any compensation or benefits payable under
this Agreement may be subject to Section 409A of the Code and related Department
of Treasury guidance (including such Department of Treasury guidance as may be
issued after the Effective Date), the Company and the Executive shall work
together to adopt such amendments to this Agreement or adopt other policies or
procedures (including amendments, policies and procedures with retroactive
effective), or take any other commercially reasonable actions necessary or
appropriate to (i) exempt the compensation and benefits payable under this
Agreement from Section 409A of the Code and/or preserve the intended tax
treatment of the compensation and benefits provided with respect to this
Agreement, or (ii) comply with the requirements of Section 409A of the Code and
related Department of Treasury guidance.


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          5. Payments to Executive at Termination.

          (a) Consequences of Termination. If the Executive's employment with
the Company and SS&C is terminated for any reason, the Executive (or, in the
case of Executive's death, the Executive's estate and/or beneficiaries) shall be
entitled to the following: (i) unpaid Base Salary through the date of the
termination; (ii) payment of any Annual Bonus earned with respect to a completed
fiscal year of the Company that is unpaid as of the date of termination; and
(iii) any benefits due to Executive under any Employee Benefit Plan and any
payments due to the Executive under any Company or SS&C policy, program,
arrangement or agreement (including, without limitation, reimbursement for
previously incurred expenses) (collectively, the "Accrued Amounts").

          (b) Termination Without Cause; for Good Reason; Nonrenewal by the
Company. The Company may terminate Executive's employment without Cause and
Executive may terminate his employment for Good Reason (notwithstanding anything
in this Agreement to the contrary, "Good Reason" shall not exist unless the
provisions of Section 5(f) are complied with), in each case upon thirty 30 days
written notice, and the Executive's employment may be terminated upon a Notice
of Nonrenewal by the Company. Upon a termination of the Executive's employment
by the Company without Cause, as a result of the Company's Notice of Nonrenewal,
or by the Executive for Good Reason, the Executive shall be entitled to, subject
to the Executive's signing, within thirty (30) days following the date the
Company provides the Executive with a Release, and not revoking a Release, the
following:

               (i) severance payments totaling the sum of 200% of the
Executive's Base Salary and 200% of Executive's Target Annual Bonus, payable
promptly upon termination (or, if later, payment shall be made at the earliest
time permitted under the terms of the agreements governing any senior credit
facilities to which the Company or any of its subsidiaries may be a party);
provided that if Executive's termination is for Good Reason due to a reduction
in any such amount, the amount used in calculating the severance payment shall
be that in effect prior to the event giving rise to Good Reason;

               (ii) the Executive's outstanding Options, whether or not then
exercisable, shall become exercisable with respect to 50% of the unvested shares
subject to the Options, as determined on the date of termination, and shall,
except with respect to the Assumed Options which will remain exercisable in
accordance with their terms, remain exercisable for the balance of their
ten-year terms as if no termination had occurred (subject to earlier termination
as provided in the applicable plan, for example, in connection with a Change in
Control);

               (iii) 50% of the vesting restrictions on Restricted Shares shall
lapse;

               (iv) the Assumed Options shall become fully vested on the date of
termination; and

               (v) three years of Company paid premiums for Executive's
continuation of coverage under the Company's group medical, dental and vision
benefit plans and, to the extent permitted under the terms of the Company's
group medical, dental and vision benefit plans, continued coverage, at the
Executive's cost, for the remainder of Executive's life.


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Notwithstanding anything to the contrary in this Section 5 or Section 10, no
payments in Section 5 or Section 10 will be paid during the six-month period
following Executive's termination of employment unless the Company determines,
in its good faith judgment, that paying such amounts at the time or times
indicated in such Sections would not cause Executive to incur an additional tax
under Section 409A of the Code (in which case such amounts shall be paid at the
time or times indicated in such Sections). If the payment of any amounts are
delayed as a result of the previous sentence, on the first day following the end
of the six-month period, the Company will pay Executive a lump-sum amount equal
to the cumulative amounts that would have otherwise been previously paid to
Executive under this Agreement. Thereafter, payments will resume in accordance
with Section 5 and Section 10, as applicable.

          (c) Termination Due to Death or Disability. The Company shall have the
right to terminate Executive's employment as a result of Executive's Disability
(as defined below) upon thirty 30 days written notice and Executive's employment
shall automatically terminate upon the death of the Executive. In the event that
Executive's employment is terminated during the Term due to Executive's
Disability or death, Executive (or in the event of Executive's death, his
estate) shall be entitled to subject to, in the case of Disability, the
Executive's signing, within thirty (30) days following the date the Company
provides the Executive with a Release, and not revoking a Release, the following
benefit and shall not be entitled to payments or benefits under Section 5(b):
(i) disability or death benefits (as applicable) in accordance with the Company
or SS&C provided insurance programs and arrangements in which Executiv