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                                                                   EXHIBIT 10.23

                                 May 18, 1999

Mr. Mark Schenecker


Dear Mr. Schenecker:

          This letter (the "Agreement") will confirm the agreement between Dast
Corporation d/b/a Microcom Technologies, a New York corporation (the "Company"),
and you relating to your employment by the Company.

          1.   EMPLOYMENT. The Company hereby employs you, and you hereby agree
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to serve as the Chief Technology Officer of the Company during the Term of
Employment (as hereinafter defined). In such capacity, you shall be responsible
for supervising, managing and coordinating the information technology function
of the Company, including the design, operation and function of the PartMiner
web site. In addition, your responsibilities may include operational and
strategic responsibilities associated with the core business of the Company as
it exists today. You shall report directly to Daniel Nissanoff, President of the
Company. In the event that any changes in your responsibilities are made by the
Company, such changes will be commensurate with your demonstrated abilities. Any
changes made by the Company in the foregoing reporting arrangements will be
discussed with you prior to implementing such changes. You agree also to perform
such senior executive services customary to such position as shall from time to
time be assigned to you and, in the absence of such assignment, such senior
executive services customary to such position as are necessary to the operations
of the Company. You agree to use your best efforts to promote the interests of
the Company and to devote all of your working time and energies to the business
and affairs of the Company during the Term of Employment (as hereinafter
defined). Although you may be associated with or invest in other companies, you
will not allow such activities to interfere with your services to the Company.

          2.   TERM OF EMPLOYMENT. The term of employment hereunder shall be for
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the period commencing on May 24, 1999 and shall end on May 24, 2001 (the "Term
of Employment"), unless earlier terminated pursuant to the provisions of Section
5 hereof.

          3.   COMPENSATION; EXPENSES; BENEFITS.
               --------------------------------

          (a)  Base Salary. As compensation for the services hereunder during
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the Term of Employment, the Company shall pay you a base salary of $200,000 per
annum. Such salary shall be payable in appropriate bi-weekly installments to
conform with the regular payroll dates for salaried personnel of the Company and
will be considered for adjustment annually, in accordance with the Company
policy, based on the Company's evaluation of your performance

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for the preceding fiscal year.

          (b)  Benefits. You will receive the benefits that the Company provides
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its senior executives generally, including employee health insurance benefits.
Your vacation will begin to accrue as of the date hereof, in accordance with the
Company's existing policy, up to a maximum of three (3) weeks per year.

          (c)  Expenses. During the Term of Employment, you shall be entitled to
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be reimbursed for all reasonable expenses incurred by you in performing services
hereunder in accordance with the policies and procedures established by the
Company from time to time. In addition, during the first year of the Term of
Employment, the Company will reimburse you for reasonable lodging in New York
City and travel expenses incurred for travel between New York City, New York and
Colorado.

          (d)  Stock Options. Subject to approval by the shareholders and
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directors of the Company of a proposed 1999 Stock Plan of the Company (the
"Plan"), the Company shall grant or cause to be granted to you options to
purchase shares of common stock of the Company. The exercise price of these
options shall be determined based on a valuation of the Company of $50,000,000.
The options shall be granted pursuant to the Plan and will be subject to the
terms and conditions of the Plan and of a nonqualified stock option agreement to
be entered into between you and the Company. Subject to the foregoing, the total
number of shares covered by these options shall vest as follows: (i) one third
of such options shall vest on May 24, 1999, (ii) one third of such options shall
vest on May 24, 2000, and (iii) one third of such options shall vest upon the
public offering by the Company of its securities pursuant to a registration
statement under the Securities Act of 1933, as amended.

          4.   COVENANT NOT TO COMPETE; INTELLECTUAL PROPERTY;
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               CONFIDENTIALITY; ENFORCEABILITY; BREACH.
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(a)  Covenant Not To Compete. You acknowledge that you are expected to play
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a very important role in the on-going development of the Company, that you will
have detailed knowledge of the Company's business and its plans for the future,
that you will have a fiduciary relationship with the Company, and you will be
receiving substantial compensation and other benefits under this Agreement.
During the Term of Employment, you shall not, directly or indirectly, advise,
manage, control, operate, be employed by or participate in the ownership,
management, operation or control of, or be connected in any manner with any
business which competes with any business of the Company. The decision of the
Board of Directors of the Company as to what constitutes a competing business
shall be final and binding upon you. For these purposes, your ownership of one
percent (1%) or less of any class of securities of a public company shall not be
considered to be competition with the Company. Notwithstanding anything
contained herein to the contrary, in the event that following the Term of
Employment, you directly or indirectly advise, manage, control, operate, become
employed by or participate in the ownership, management, operation or control
of, or become connected in any manner with any business which competes with any
business of the Company, any and all options granted to you hereunder shall
terminate whether







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or not exercisable. Notwithstanding the foregoing, you shall be permitted to
publish a book on your own time which does not interfere with your duties and
responsibilities hereunder, any revenue from which shall be yours; provided the
Company shall have the right to review and approve such book prior to
publication.

          (b)  Intellectual Property. You agree that all ideas, inventions,
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trade secrets, marketing plans and business plans developed by you during the
Term of Employment which relate directly or indirectly to the business of the
Company, including without limitation, any process, operation, product or
improvement which may be patentable or copyrightable, will be the property of
the Company and that you will at the Company's request and cost do whatever is
necessary to secure the rights thereto by patent, copyright or otherwise to the
Company.

          (c)  Confidentiality. You agree that you will not divulge to anyone
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(other than the Company or any persons employed or designated by the Company)
any knowledge or information of any type whatsoever of a confidential nature
relating to the business of the Company, including, without limitation, any and
all types of ideas, inventions, trade secrets, marketing plans, business plans,
and processes, operations, products or improvements which may be patentable or
copyrightable ("Confidential Information"). You further agree not to disclose,
publish or make use of any such Confidential Information without the prior
written consent of the Company. The term "Confidential Information" does not
include any information which (i) at the time of disclosure or thereafter is
generally available to and known to the public (other than as a result of
disclosure directly or indirectly by you), (ii) was available to you on a
non-confidential basis from a source other than the Company or its
representatives and advisors, provided that such source is not in breach of any
obligations of confidentiality to the Company, or (iii) has been independently
acquired or developed by you without violating any of your obligations pursuant
to this Agreement. The provisions set forth in this section shall survive the
termination or cancellation of this Agreement.

          (d)  Enforceability. You recognize and agree that the limitations
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placed on you by this Section 4 are reasonable and are required for the
protection of the Company. You agree that if any such limitation is determined
in arbitration or by a court of competent jurisdiction to be unenforceable, you
agree and submit to the reduction of such limitation as the court or
arbitrator(s) deem reasonable. The limitations placed on you by this Section 4
are of the essence of this Agreement and they shall be construed and enforced
independently. The existence of any claim or cause of action against the Company
by you shall not constitute a defense against the enforcement of these
limitations on you.

          (e)  Breach. You acknowledge and agree that money damages would not
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               adequately compensate the Company in the event of breach by you
               of any provision of this Section 4. Consequently, you agree that
               the Company shall be entitled, without the necessity of proving
               actual damages, to obtain damages for any breach of this Section
               4, to enforce specific performance by you of any provision of
               this Section 4, or to obtain temporary and

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               permanent injunctive relief from any court of competent
               jurisdiction for enforcement of the provisions of this Section
               4.

          5.   TERMINATION.
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          (a)  General. Your employment hereunder shall terminate as provided in
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Section 2 hereof and may be earlier terminated in accordance with the provisions
of this Section 5. Unless earlier terminated in accordance with the provisions
of this Section 5, the Company shall provide you with at least (30) days notice
prior to the termination of your employment as provided in Section 2 if the
Company does not intend to renew this Agreement.

          (b)  Death and Disability. Your employment under this Agreement shall
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terminate upon (i) your death; or (ii) in the event you become disabled, at the
option of the Company, thirty (30) days after the date on which the Company
shall have given you written notice of the termination of your employment
because of your physical or mental incapacity on a permanent basis. You shall be
deemed to be physically or mentally incapacitated on a permanent basis if you
are unable, by reason of any physical or mental incapacity, for a period of
ninety (90) substantially consecutive days or for shorter periods aggregating
one hundred twenty (120) days or more during any twelve (12) month period, to
perform your duties as Chief Technology Officer of the Company in a reasonably
satisfactory manner. In the event of any disagreement between you and the
Company as to whether you are physically or mentally incapacitated on a
permanent basis so as to permit the Company to terminate your employment
pursuant to this subparagraph (b), the question of such permanent incapacity
shall be submitted for decision to an impartial and reputable physician in New
York County, New York (the "Deciding Doctor") chosen by mutual agreement of the
Company and you or, failing such agreement, the Deciding Doctor shall be chosen
by two physicians from New York County, New York (one of whom shall be selected
by the Company and the other by you). The decision of the Deciding Doctor
regarding your capacity or incapacity shall be final and binding on the Company
and you. You shall submit to any medical examinations reasonably necessary to
enable the Deciding Doctor to make a decision regarding your capacity or
incapacity. If your employment is terminated under this Section 6(b), all
compensation and rights to benefits from the Company shall cease on the date of
your death or the date specified in the notice of termination for disability
(other than as may have already accrued as of the date of termination or as
expressly provided in plans in which you participated at the date of
termination).

          (c)  Termination by the Company for "Cause". The Company may terminate
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your employment for "cause"; provided, however, the Company shall have given you
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written notice specifying in reasonable detail the reason therefor, and ten (10)
days after receipt of such notice in which to cure such "cause", if capable of
cure. For the purposes of this Agreement, and event or occurrence constituting
"cause" shall mean knowingly or recklessly causing material injury to the
Company; willful misconduct in the performance of, or a willful failure to
perform, your duties; commission of dishonest or fraudulent conduct whether or
not in connection with your employment, or unlawful behavior involving moral
turpitude whether or not in connection with your employment; or breach or
violation of this Agreement. If your employment is terminated


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under this Section 5(c), all compensation and rights to benefits from the
Company shall cease on the date of termination (other than as may have already
accrued as of the date of termination or as expressly provided in plans in which
you participated at the date of termination); provided, however, that the
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restrictions on your activities contained in Section 4 hereof shall continue in
effect as provided therein.

          (d)  Termination by Voluntary Resignation. You may terminate your
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employment upon thirty (30) days written notice to the Company at any time after
May 24, 2000 in your sole discretion for any reason or for no reason at all. If
your employment is terminated under this Section 5(d), all compensation and
rights to benefits from the Company shall cease (other than as may have already
accrued as of the date of termination or as expressly provided in plans in which
you participated at the date of termination). Nothwithstanding the foregoing, if
your employment is terminated under this Section 5(d), any options granted to
you in accordance with this Agreement shall immediately terminate on the date of
such notice of termination to the extent not then exercisable.

          6.   ASSIGNMENT. This Agreement is a personal contract, and except as
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specifically set forth herein, your rights, obligations and interests herein may
not be sold, transferred or assigned. The Company may freely assign this
Agreement and any of its rights, obligations and interests hereunder. This
Agreement shall be binding upon and inure to the benefit of each party's
successors and permitted assigns.

          7.   ENTIRE AGREEMENT; GOVERNING LAW; CAPTIONS. This Agreement
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contains the entire agreement between the parties with respect to your
employment by the Company, and the validity, interpretation, construction and
performance of this Agreement shall be governed by the laws of the State of New
York. You hereby agree that any agreement or arrangement existing prior to the
date hereof regarding your employment by the Company is hereby terminated and
superseded by this Agreement. This Agreement may not be changed orally, but only
by agreement in writing signed by the party against whom enforcement of any
waiver, change, modification or discharge is sought. Section and paragraph
headings are for convenience of reference only and shall not be considered a
part of this Agreement.

          8.   NOTICES. Any notices or other communications required or
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permitted hereunder shall be in writing and shall be deemed given (a) on the
same day if given by hand, (b) on the third business day after mailing if given
by registered or certified mail, return receipt requested, postage prepaid, (c)
on the next business day after it was deposited with the courier service if sent
by reputable overnight courier, or (d) when sent if given by facsimile with
confirmation, addressed to you at [address] or to the Company at its offices at
16 East 52/nd/ Street, New York, New York 10022, Attention: President (fax no.
212-758-2559), with a copy to: Gould & Wilkie LLP, One Chase Manhattan Plaza,
58th floor, New York, New York 10005, Attention: Michael R. Manley, Esq. (fax
no.: 212-809-6890) or such other address as shall have been specified in writing
by either party to the other.

          9.   ARBITRATION. Except as provided by Section 4(e) of this
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Agreement, any dispute or controversy under or in connection with this Agreement
shall be settled exclusively

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by arbitration in New York, New York by one arbitrator in accordance with the
rules of the American Arbitration Association then in effect. Judgment may be
entered upon the arbitrator's award in any court having jurisdiction. The costs
and expenses (including reasonable attorneys' fees and disbursements) of the
prevailing party in any such dispute or controversy shall be reimbursed by the
other party.

          10. RIGHT TO WITHHOLD. The Company shall have the right to make all
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appropriate withholdings from your salary and other compensation under federal,
state and local tax laws.

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     If the foregoing accurately reflects the agreement between us, please
confirm your acceptance and agreement by signing the attached copy of this
Agreement and return the same to me.


                                   Sincerely,

                                   DAST CORPORATION D/B/A
                                   MICROCOM TECHNOLOGIES


                                   /s/ Daniel Nissanoff
                                   ------------------------------------------
                                   Name: Daniel Nissanoff
                                   Title: President



ACCEPTED AND AGREED:

/s/ Mark Schenecker
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Mark Schenecker

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