<PAGE>

                                                                   EXHIBIT 10.13


                     FIRST AMENDMENT TO EMPLOYMENT AGREEMENT

This First Amendment to that certain Employment Agreement dated as of April 21,
2005 (the "First Amendment") is made as of the February 17, 2006 (the "Effective
Date") by and between Open Solutions Inc. ("OSI") and Louis Hernandez, Jr.
("Hernandez").

                              W I T N E S S E T H:

WHEREAS, OSI and Hernandez are parties to that certain Employment Agreement
dated as of April 21, 2005 (the "Agreement"); and

WHEREAS, OSI and Hernandez wish to amend the Agreement as set forth below;

NOW, THEREFORE, in consideration of the mutual covenants herein contained and
other good and valuable consideration, the receipt and sufficiency of which is
hereby acknowledged, IT IS AGREED as follows:

1.       OSI and Hernandez hereby agree to replace (y) of Section 2.3 with the
following:

         "(y) full vesting of any stock options and restricted stock previously
         granted to you, and"

2.       OSI and Client hereby agree to replace Section 2.4 of the Agreement
with the following:

         "For purposes of this Agreement, the term a "Change in Control" shall
         mean and be deemed to have occurred if (i) any "person" (as such term
         is used in Section 13(d) and 14(d) of the Securities Exchange Act of
         1934, as amended), other than a trustee or other fiduciary holding
         securities under an employee benefit plan of the Company or a
         corporation owned directly or indirectly by the stockholders of the
         Company in substantially the same proportions as their ownership of
         stock of the Company, is or becomes the "beneficial owner" (as defined
         in Rule 13d-3 under said Act), directly or indirectly, of securities of
         the Company representing 35% or more of the total voting power
         represented by the Company's then outstanding voting securities, or
         (ii) during any period of 12 consecutive months, individuals who at the
         beginning of such period constitute the Board of Directors of the
         Company and any new director whose election by the Board of Directors
         or nomination for election by the Company's stockholders was approved
         by a vote of at least two-thirds (2/3) of the directors then still in
         office who either were directors at the beginning of the period or
         whose election or nomination for election was previously so approved,
         cease for any reason to constitute a majority thereof, or (iii) the
         stockholders of the Company approve a merger or consolidation of the
         Company with any other corporation or entity, other than a merger or
         consolidation that would result in the voting securities of the Company
         outstanding immediately prior thereto continuing to represent (either
         by remaining outstanding or by being converted into voting securities
         of the surviving entity) at least 80% of the total voting power
         represented by the voting securities of the Company or such surviving
         entity outstanding immediately after such merger or consolidation, or
         the stockholders of the Company approve a plan of complete liquidation
         of the Company or an agreement for the sale or disposition by the
         Company, in one transaction or a series of transactions, of all or
         substantially all the Company's assets."


<PAGE>

3.       Except as otherwise set forth herein, all terms and provisions
contained in the Agreement shall remain in full force and effect.

4.       The Agreement, as hereby amended, shall be binding upon the parties
hereto, their permitted successors and assigns.

IN WITNESS WHEREOF, the parties have executed this amendment effective as of the
Effective Date.

LOUIS HERNANDEZ, JR.                      OPEN SOLUTIONS INC.


By    /s/ Louis Hernandez, Jr.            By    /s/ Samuel F. McKay
      -------------------------------           --------------------------------
                                                Samuel F. McKay
                                                Chairman, Compensation Committee
Date: as of February 17, 2006             Date: February 17, 2006
      -------------------------------           --------------------------------





Confidential                                                         Page 2 of 2