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                                                                    EXHIBIT 10.7

                                JOINDER AGREEMENT

      Reference is made to that certain Joint and Several Continuing Guaranty
Agreement dated as of April 13, 2005 (as amended, amended and restated,
supplemented or otherwise modified from time to time, the "GUARANTY"), by OMR
SYSTEMS CORPORATION, a New Jersey corporation and each Joinder Party from time
to time becoming a party thereto (collectively, "GUARANTOR"), in favor of FLEET
NATIONAL BANK, a Bank of America Company ("LENDER") as Lender and L/C Issuer (as
such terms are defined in the Credit Agreement).

                              W I T N E S S E T H:

      WHEREAS, SS&C TECHNOLOGIES, INC., a Delaware corporation ("BORROWER") has
entered into a certain Credit Agreement dated as of April 13, 2005 (as amended,
amended and restated, supplemented or otherwise modified from time to time, the
"CREDIT AGREEMENT"), pursuant to the terms and subject to the conditions of
which Lender shall from time to time extend Committed Loans in an amount at any
one time outstanding not to exceed $75,000,000; and

      WHEREAS, capitalized terms used herein and not otherwise defined shall
have the respective meanings ascribed to them in the Credit Agreement; and

      WHEREAS, Guarantor has entered into the Guaranty in order to induce the
Lender to make the Committed Loans to the Borrower; and

      WHEREAS, pursuant to Section 6.12 of the Credit Agreement, under certain
circumstances from and after the date of the Credit Agreement, certain Domestic
Subsidiaries shall be required to become a Guarantor under the Guaranty
Agreement by executing a Joinder Agreement.

      The undersigned Subsidiary (the "JOINDER PARTY") is executing this joinder
agreement ("JOINDER AGREEMENT") to the Guaranty Agreement in order to induce the
Lender to make additional Committed Loans and as consideration for the Committed
Loans previously made.

      NOW, THEREFORE, the Lender and the Joinder Party hereby agree as follows:

   A.    JOINDER. In accordance with Section 6.12 of the Credit Agreement, the
         Joinder Party, by its signature below, becomes a Guarantor under the
         Guaranty Agreement, with the same force and effect as if originally
         named therein as a Guarantor.

   B.    REPRESENTATIONS AND WARRANTIES. The Joinder Party hereby (a) agrees to
         all the terms and provisions of the Guaranty Agreement applicable to it
         as a Guarantor thereunder, and (b) makes each of the representations
         and warranties made by it as a Guarantor thereunder (except that any
         representation and warranty that is made as of a specified date shall
         be reaffirmed as of such date) on and as of the date hereof. Each
         reference to a Guarantor in the Guaranty Agreement shall be deemed to
         include the Joinder Party. Each reference in the Credit Agreement to a
         Guarantor shall be deemed to include the Joinder Party.

   C.    SEVERABILITY. Any provision of this Joinder Agreement which is
         prohibited or unenforceable in any jurisdiction shall, as to such
         jurisdiction, be ineffective to the extent of such prohibition or
         unenforceability without invalidating the remaining provisions hereof,
         and any such prohibition or unenforceability in any jurisdiction shall
         not invalidate or render unenforceable such provision in any other
         jurisdiction.

   D.    COUNTERPARTS. This Joinder Agreement may be executed in counterparts,
         each of which shall constitute an original. Delivery of an executed

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         signature page to this Joinder Agreement by facsimile transmission
         shall be as effective as delivery of a manually executed counterpart of
         this Joinder Agreement.

   E.    NO WAIVER. Except as expressly supplemented hereby, the Guaranty
         Agreement shall remain in full force and effect.

   F.    NOTICES. All notices, requests and demands to or upon the Joinder
         Party, the Lender and the L/C Issuer shall be governed by the terms of
         Section 9.02 of the Credit Agreement.

   G.    GOVERNING LAW. This agreement and the rights and obligations of the
         parties hereunder shall be construed in accordance with and governed by
         the law of the State of New York, without regard to conflicts of laws
         principles that would require the application of the laws of another
         jurisdiction.

      IN WITNESS WHEREOF, the undersigned have caused this Joinder Agreement to
be duly executed and delivered by their duly authorized officers as of the 4th
day of August 2005.

                                      Financial Models Company Ltd.

                                      By: /s/ Patrick J. Pedonti
                                          -------------------------------

                                          Name: Patrick J. Pedonti

                                          Title: Director

                                      Address for Notices:

                                      c/o SS&C Technologies, Inc

                                      80 Lamberton Road

                                      Windsor, CT 06095

                                      Attn: Patrick J. Pedonti

                                      FLEET NATIONAL BANK,

                                      a Bank of America Company

                                      By: /s/ Richard J. Zilewicz
                                          -------------------------------
                                          Name: Richard J. Zilewicz

                                          Title: Market President