<PAGE>

                                                                   EXHIBIT 10.1

                                 LOAN AGREEMENT


         THIS LOAN AGREEMENT (this "AGREEMENT") is made as of April 14, 2000, by
and between Wyn Lewis ("BORROWER") and Carreker-Antinori, Inc., a Delaware
corporation ("LENDER" or "COMPANY").

1.       THE LOAN.

         A. Subject to the terms of this Agreement, Lender agrees to make a loan
         (the "LOAN") to Borrower for the purpose of Borrower paying alternative
         minimum taxes in connection with the exercise by Borrower of incentive
         stock options to purchase shares of Common Stock, par value $.01 per
         share, of the Company ("ISO SHARES").

         B. Lender agrees to loan Borrower an aggregate principal amount of
         $150,000 one hundred and fifty thousand dollars ("LOAN AMOUNT").

2.       NOTES.

         A. The Loan shall be evidenced by a Promissory Note and Pledge
         Agreement, in the form of EXHIBIT A attached to this Agreement, which
         shall be for the Loan Amount, dated the date of this Agreement, and
         executed and delivered by Borrower (the "LOAN NOTE").


3.       INTEREST. Interest shall accrue from the date of the Notes, at the
         applicable rate set forth in the Notes, on the principal outstanding
         balance of the Loans. All past due interest and all past due principal
         shall bear interest at the highest rate for which the undersigned may
         legally contract under applicable law.

4.       PAYMENT.

                  A. The Loan shall mature on May 31, 2001, at which time the
         Loan Amount together with any unpaid accrued interest thereon, shall be
         due and payable, unless sooner paid or accelerated in accordance with
         the terms of the Loan Note or this Agreement. Accrued interest payable
         under the Loan Note shall be due and payable on the maturity date.

5.       SECURITY. Borrower acknowledges that the Notes are each secured by a
         separate Pledge Agreement dated as of the date of the Loan Note and Tax
         Note, respectively.

6.       REPRESENTATIONS. Borrower represents and warrants to Lender as follows:

         A. USE OF PROCEEDS. The Borrower shall use the proceeds from the Tax
         Loan for the sole purpose of paying the Borrower's AMT Tax Liability.

         B. COOPERATION WITH LENDER'S AUDITORS AND DELIVERY OF FINANCIAL
         STATEMENTS. Borrower agrees to cooperate with Lender's auditors in
         connection with any review by the auditors of the Notes and, at the
         request of Lender or its auditors, shall provide personal financial
         information to Lender and its auditors to verify that Borrower has the
         financial capability to discharge Borrower's obligations under the
         Notes.


LOAN AGREEMENT -- PAGE 1

<PAGE>



7.       EVENTS OF DEFAULT. Borrower shall be in default under this Agreement if
         any of the following events (an "Event of Default") occur:

         A. Default shall be made in the payment of any installment of principal
         of or interest upon the Notes or any other obligation of Borrower to
         Lender when due and payable, whether at maturity or otherwise, and such
         default continues for five (5) days after written notice thereof by
         Lender to Borrower; or

         B. Default shall be made in the performance of any term, covenant, or
         agreement (except for the payment of amounts subject to subsection 6(A)
         of this Agreement) contained in this Agreement, or the Notes and such
         default continues for thirty (30) days after written notice thereof by
         Lender to Borrower; or

         C. Any representation or warranty made by Borrower in this Agreement,
         or any financial statement, certificate, report, or opinion submitted
         to Lender in connection with the Notes or pursuant to the requirements
         of this Agreement that prove to have been incorrect or misleading in
         any material respect when made; or

         D. (1) Borrower makes an assignment for the benefit of creditors,
         admits in writing his or her inability to pay his or her debts
         generally as they become due, files a petition in bankruptcy, is
         adjudicated insolvent or bankrupt or an order for relief is entered,
         petitions or applies to any tribunal for any receiver or any trustee of
         Borrower or any substantial part of his or her property, commences any
         action relating to Borrower under any reorganization, arrangement,
         readjustment of debt, dissolution, or liquidation law or statute of any
         jurisdiction, whether now or hereafter in effect, or (2) if there is
         commenced against Borrower any such action, or Borrower by any act
         indicates his or her consent to or approval of the entry of an order
         for relief or for the appointment of any receiver or trustee for
         Borrower or any substantial part of his or her property, or suffers any
         such receivership or trustee to continue undischarged.

8.       LENDER REMEDIES.


         A.       Upon the occurrence and during the continuation of an Event of
                  Default (other than the Event of Default described in
                  subsection 6(D)(2) of this Agreement), Lender may, at its
                  election, declare the outstanding principal of and the unpaid
                  interest on the Notes and any other indebtedness of Borrower
                  to Lender to be due and payable immediately.


         B.       Upon the occurrence of an Event of Default described in
                  subsection 6(D)(2) of this Agreement, and if any action
                  referred to in subsection 6(D)(2) of this Agreement is not
                  dismissed within thirty (30) days of the filing thereof or an
                  order for relief is entered sooner, all outstanding principal
                  of and the unpaid interest on the Notes shall be due and
                  payable immediately.

         C.       Upon the occurrence and during a continuation of an Event of
                  Default, Lender may, at its election, also exercise any of
                  Lender's other remedies under each Pledge Agreement.


LOAN AGREEMENT -- PAGE 2

<PAGE>



9.       MISCELLANEOUS.

         A.       EXPENSES. Borrower shall pay all of the reasonable
                  out-of-pocket expenses, including reasonable attorneys' fees,
                  incurred by Lender in connection with the enforcement of this
                  Agreement, each Pledge Agreement or in the collection of the
                  Notes.

         B.       CUMULATIVE RIGHTS AND NO WAIVER. Each and every right granted
                  to Lender under this Agreement, the Notes and each Pledge
                  Agreement or under any other document delivered hereunder or
                  in connection herewith or allowed it by law or equity, shall
                  be cumulative of and may be exercised in addition to any and
                  all other rights of Lender. No delay in exercising any right
                  shall operate as a waiver thereof, nor shall any single or
                  partial exercise by Lender of any right preclude any other or
                  future exercise thereof or the exercise of any other right.
                  Any of the foregoing covenants and disagreements may be waived
                  by Lender, but only in writing. Except as otherwise provided
                  in this Agreement, Borrower expressly waives any presentment,
                  demand, protest, or other notice of any kind, including, but
                  not limited to, notice of intent to accelerate and notice of
                  acceleration.

                  No notice to or demand on Borrower in any case shall, of
                  itself, entitle Borrower to any other or further notice or
                  demand in similar or other circumstances. No delay or omission
                  by Lender in exercising any power or right hereunder shall
                  impair any such right or power or be construed as a waiver
                  thereof or any acquiescence therein, nor shall any single or
                  partial exercise of any such power preclude other or further
                  exercise thereof, or the exercise of any other right or power
                  hereunder.

         C.       APPLICABLE LAW. This Agreement and the rights and obligations
                  of the parties hereunder shall be governed by and interpreted
                  in accordance with the laws of the State of Texas.

         D.       AMENDMENT. No modification, consent, amendment, or waiver of
                  any provision of this Agreement, nor consent to any departure
                  by Borrower therefrom, shall be effective unless the same
                  shall be in writing and signed by the Lender and then shall be
                  effective only in the specific instance and for the specific
                  purpose for which given. This Agreement is binding upon
                  Borrower and his or her successors and inures to the benefit
                  of Lender and its successors and assigns.

         E.       GENDER. Words used in this Agreement of any gender shall
                  include each other gender where appropriate.

         F.       CONFLICT. In the event of any conflict between the provisions
                  of this Agreement and provisions of the Notes or each Pledge
                  Agreement, the provisions of this Agreement shall prevail.

         G.       NOTICES. Except as otherwise provided in this Agreement, any
                  notices or other communications required or permitted
                  hereunder shall be in writing and shall be deemed to have been
                  given upon (1) receipt if delivered by hand delivery, or (2)
                  deposit in a regularly maintained mail receptacle of the
                  United States Postal Service, postage prepaid, registered or
                  certified, return receipt requested, if to Borrower,
                  _____________________________________________________________
                  _____________________________________ or, if to Lender, to
                  4055 Valley View Lane, Suite 1000, Dallas, Texas 75244, or
                  such other address as shall be furnished in writing by either
                  party.

         H.       COUNTERPARTS. This Agreement may be executed simultaneously or
                  in two or more counterparts, each of which shall be an
                  original, and such counterparts shall constitute one and the
                  same instrument.


LOAN AGREEMENT -- PAGE 3

<PAGE>

         I.       NUMBER. Where appropriate, the use of the singular number
                  shall be construed to include the plural, and vice versa.

10. FINAL AND ENTIRE AGREEMENT. THIS WRITTEN AGREEMENT (INCLUDING THE PROMISSORY
NOTE AND PLEDGE AGREEMENT WHICH IS A PART OF THIS AGREEMENT) REPRESENTS THE
FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF
PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE
NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.



                  [Remainder of Page Intentionally Left Blank]


LOAN AGREEMENT -- PAGE 4

<PAGE>



         IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement as of the date first above written.



Borrower:                                    Lender:

                                             CARREKER-ANTINORI, INC., a Delaware
                                             corporation


--------------------------------             By:
Signature of Borrower                           -------------------------------
                                                J. D. (Denny) Carreker, Jr.
                                                Chairman of the Board and Chief
                                                Executive Officer
--------------------------------
Printed Name of Borrower


LOAN AGREEMENT -- PAGE 5

<PAGE>




                                    EXHIBIT A


                      PROMISSORY NOTE AND PLEDGE AGREEMENT



$150,000                                                          April 14, 2000


         For value received, Wyn Lewis ("Maker") hereby unconditionally promises
to pay to the order of Carreker-Antinori, Inc., a Delaware corporation ("Lender"
or "Company") the principal sum of $150,000 ("Loan Amount"), together with
interest on the unpaid balance thereof at a rate equal to 8.0%. Accrued and
unpaid interest on this Note shall be paid on May 31, 2001. The unpaid Loan
Amount will be due and payable in full on or before May 31, 2001 ("Maturity
Date"). All payments shall be made at the offices of Carreker-Antinori, Inc.,
4055 Valley View Lane, Suite 1000, Dallas, Texas 75244, or such other place as
Lender may designate in writing. Maker may prepay the outstanding Loan Amount in
whole or in part at any time without penalty. Maker shall apply any bonus
payments received from the Company, net of applicable taxes, to the Loan Amount
and accrued and unpaid interest on the Note.

         The Maker and all endorsers, sureties and guarantors of this Note
hereby jointly and severally waive demand, presentment for payment, protest,
notice of protest, notice of intent to accelerate, notice of acceleration,
diligence in collecting, the bringing of any suit against any party and any
notice of or defense on account of any extensions, renewals, or partial payments
of this Note, or any delay, indulgence or other act by any holder hereof whether
before or after maturity.

         This Note and the rights and duties of the parties hereunder shall be
governed by the laws of the State of Texas. As allowed by law, this Note is
performable by Maker in Dallas County, Texas.

         DEFAULT NOTICE AND REMEDIES. If Maker fails to perform any obligation
created by this Note or a default by Maker occurs, Lender may declare this Note
immediately due and payable in whole or in part, may enforce payment thereof and
exercise any and all of its rights and remedies hereunder or as otherwise
provided by law. Maker expressly waives presentment, demand, notice of
non-payment, notice of acceleration or other notice of any kind. Interest shall
accrue on the full amount of any overdue installments at the highest rate
permitted by law. The acceptance by Lender at any time and from time to time of
part payment on this Note shall not be deemed to be a waiver of any event of
default then existing. No waiver by Lender of any right hereunder or waiver by
Lender of any default by Maker shall operate as a waiver of any other right or
any other default.

         If Maker's employment with the Lender terminates for any reason, Lender
may declare this Note immediately due and payable in whole or in part, enforce
payment thereof, and exercise any and all of its rights and remedies hereunder.


                                                                        --------
                                                                        INITIALS

<PAGE>



         COLLATERAL ASSIGNMENT.  The Maker pledges the following to Lender as
security for this Note:

                  1.       PLEDGE:

                  In consideration for the Loan Amount, receipt of which is
acknowledged, Maker hereby grants a security interest to the Lender in _______
shares (the "Pledged Shares") of the Common Stock, $.01 par value per share, of
the Company. Maker agrees not to dispose of such Pledged Shares until the Loan
Amount and all interest accrued thereon is paid. Maker appoints J. D. (Denny)
Carreker, Jr. or his designee as his attorney in fact to arrange for the
transfer of the Pledged Shares to the Lender in the event of a default in the
terms of this Note from Maker to Lender.

                  2.       DIVIDENDS:

                  During the term of this pledge and as long as Maker is not in
default in the performance of any of the terms of this Note, Maker shall be
entitled to receive all dividends on the Pledged Shares.

                  3.       VOTING RIGHTS:

                  During the term of this pledge and as long as Maker is not in
default in the performance of any of the terms of this Note, Maker shall have
the right to vote the Pledged Shares and to the extent required, Lender shall
execute due and timely proxies in favor of the Maker to this end.

                  4.       REPRESENTATIONS:

                  Maker represents and warrants that there are no restrictions
upon the transfer of the Pledged Shares (except as specified by the restrictive
legend which may appear upon the face of the stock certificate) and that Maker
has the right to transfer such shares free of encumbrances and without obtaining
the consents of other parties.

                  5.       ADJUSTMENTS:

                  In the event that, during the term of this pledge, any share
dividend, reclassification, readjustment or other changes declared are made in
the capital structure of the Company, all new, substituted and additional
shares, or other securities issued by reason of any such change shall be held
under the terms of this Note in the same manner as the shares originally pledged
hereunder.

                  6.       WARRANTS AND RIGHTS:

                  In the event that during the term of this pledge, subscription
warrants or any other rights or options shall be issued in connection with the
Pledged Shares, such warrants, rights and options shall be immediately assigned
by the Lender to the Maker, and if exercised by the Maker all new shares or
other security so acquired by the Maker shall be immediately assigned to the
Lender to be held under the terms of this Note in the same manner as the shares
originally pledged hereunder.


                                                                        --------
                                                                        INITIALS

<PAGE>

                  7.       PAYMENT OF PROMISSORY NOTE:

                  Upon payment and maturity of the principal and interest due
pursuant to this Note, Lender shall direct J. D. (Denny) Carreker, Jr. or his
designee to transfer to the Maker all of the Pledged Shares and all rights
received by the Lender, if any, as a result of its record ownership thereof.

                  8.       DEFAULT WITH RESPECT TO PLEDGE OF SHARES:

                  In the event that Maker defaults in the performance of any of
the terms of this Note, Lender shall have the rights and remedies provided in
the Uniform Commercial Code in force in the state of Texas at the date of this
Note and in this connection, Lender may, upon five days notice to Maker, sent by
certified mail, and without liability for any diminution in price which may have
occurred, sell all of the Pledged Shares in such manner and for such price as
the Lender may determine. At any bona fide public sale Lender shall be free to
purchase all or a part of the Pledged Shares. Out of the proceeds of any sale,
Lender may retain an amount equal to the principal and interest then due on the
loan, plus the amount of the expenses of the sale, and shall pay any balance of
such proceeds to Maker. In the event that the proceeds of any such sale are
insufficient to cover the principal and interest of the loan, plus expenses of
the sale, Maker shall remain liable to the Lender for any deficiency.


         NOTICES. Any notices given to Maker or Lender shall be deemed effective
if in writing and mailed by registered or certified mail, postage prepaid, or
delivered in person to the addressee and receipted for, in all such instances
addressed to the respective parties at the following addresses:


         If to Lender:              Carreker-Antinori, Inc.
                                    4055 Valley View Lane, Suite 1000
                                    Dallas, TX  75244
                                    Attention: Chief Financial Officer
         If to Maker:               _______________________
                                    _______________________
                                    _______________________

         NON-ASSIGNABLE. This Note will inure to the benefit of and will be
binding upon Maker and Lender and the permitted successors and assigns of each.
Maker shall not assign any of its rights or transfer any of its obligations
under this Note without first obtaining the written consent of Lender.

         Maker acknowledges that he has read all the terms and conditions of
this Note, acknowledges receipt of a copy hereof and agrees to all of the terms
and conditions herein.




                                                --------------------------------
Dated as of May 13, 2000                        Maker:


                                                                        --------
                                                                        INITIALS