diff --git a/src/auditor-lib/auditor_api_common.c b/src/auditor-lib/auditor_api_common.c
deleted file mode 100644
index de05348f3..000000000
--- a/src/auditor-lib/auditor_api_common.c
+++ /dev/null
@@ -1,328 +0,0 @@
-/*
-  This file is part of TALER
-  Copyright (C) 2015-2017 Taler Systems SA
-
-  TALER is free software; you can redistribute it and/or modify it under the
-  terms of the GNU General Public License as published by the Free Software
-  Foundation; either version 3, or (at your option) any later version.
-
-  TALER is distributed in the hope that it will be useful, but WITHOUT ANY
-  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
-  A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License along with
-  TALER; see the file COPYING.  If not, see
-  <http://www.gnu.org/licenses/>
-*/
-/**
- * @file exchange-lib/exchange_api_common.c
- * @brief common functions for the exchange API
- * @author Christian Grothoff
- */
-#include "platform.h"
-#include "taler_json_lib.h"
-#include <gnunet/gnunet_curl_lib.h>
-#include "exchange_api_handle.h"
-#include "taler_signatures.h"
-
-
-/**
- * Verify a coins transaction history as returned by the exchange.
- *
- * @param currency expected currency for the coin
- * @param coin_pub public key of the coin
- * @param history history of the coin in json encoding
- * @param[out] total how much of the coin has been spent according to @a history
- * @return #GNUNET_OK if @a history is valid, #GNUNET_SYSERR if not
- */
-int
-TALER_EXCHANGE_verify_coin_history (const char *currency,
-				    const struct TALER_CoinSpendPublicKeyP *coin_pub,
-				    json_t *history,
-                                    struct TALER_Amount *total)
-{
-  size_t len;
-  int add;
-  struct TALER_Amount rtotal;
-
-  if (NULL == history)
-  {
-    GNUNET_break_op (0);
-    return GNUNET_SYSERR;
-  }
-  len = json_array_size (history);
-  if (0 == len)
-  {
-    GNUNET_break_op (0);
-    return GNUNET_SYSERR;
-  }
-  GNUNET_assert (GNUNET_OK ==
-                 TALER_amount_get_zero (currency,
-                                        total));
-  GNUNET_assert (GNUNET_OK ==
-                 TALER_amount_get_zero (currency,
-                                        &rtotal));
-  for (size_t off=0;off<len;off++)
-  {
-    json_t *transaction;
-    struct TALER_Amount amount;
-    const char *type;
-    struct GNUNET_JSON_Specification spec_glob[] = {
-      TALER_JSON_spec_amount ("amount",
-                              &amount),
-      GNUNET_JSON_spec_string ("type",
-                               &type),
-      GNUNET_JSON_spec_end()
-    };
-
-    transaction = json_array_get (history,
-                                  off);
-    if (GNUNET_OK !=
-        GNUNET_JSON_parse (transaction,
-                           spec_glob,
-                           NULL, NULL))
-    {
-      GNUNET_break_op (0);
-      return GNUNET_SYSERR;
-    }
-    add = GNUNET_SYSERR;
-    if (0 == strcasecmp (type,
-                         "DEPOSIT"))
-    {
-      struct TALER_DepositRequestPS dr;
-      struct TALER_CoinSpendSignatureP sig;
-      struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_fixed_auto ("coin_sig",
-                                     &sig),
-        GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
-                                     &dr.h_contract_terms),
-        GNUNET_JSON_spec_fixed_auto ("h_wire",
-                                     &dr.h_wire),
-        GNUNET_JSON_spec_absolute_time_nbo ("timestamp",
-					    &dr.timestamp),
-        GNUNET_JSON_spec_absolute_time_nbo ("refund_deadline",
-					    &dr.refund_deadline),
-        TALER_JSON_spec_amount_nbo ("deposit_fee",
-				    &dr.deposit_fee),
-        GNUNET_JSON_spec_fixed_auto ("merchant_pub",
-                                     &dr.merchant),
-        GNUNET_JSON_spec_end()
-      };
-
-      if (GNUNET_OK !=
-          GNUNET_JSON_parse (transaction,
-                             spec,
-                             NULL, NULL))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      dr.purpose.size = htonl (sizeof (dr));
-      dr.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_DEPOSIT);
-      TALER_amount_hton (&dr.amount_with_fee,
-			 &amount);
-      dr.coin_pub = *coin_pub;
-      if (GNUNET_OK !=
-          GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_WALLET_COIN_DEPOSIT,
-                                      &dr.purpose,
-                                      &sig.eddsa_signature,
-                                      &coin_pub->eddsa_pub))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      /* TODO: check that deposit fee and coin value match
-	 our expectations from /keys! */
-      add = GNUNET_YES;
-    }
-    else if (0 == strcasecmp (type,
-                              "MELT"))
-    {
-      struct TALER_RefreshMeltCoinAffirmationPS rm;
-      struct TALER_CoinSpendSignatureP sig;
-      struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_fixed_auto ("coin_sig",
-                                     &sig),
-        GNUNET_JSON_spec_fixed_auto ("rc",
-                                     &rm.rc),
-        TALER_JSON_spec_amount_nbo ("melt_fee",
-				    &rm.melt_fee),
-        GNUNET_JSON_spec_end()
-      };
-
-      if (GNUNET_OK !=
-          GNUNET_JSON_parse (transaction,
-                             spec,
-                             NULL, NULL))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      rm.purpose.size = htonl (sizeof (rm));
-      rm.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_MELT);
-      TALER_amount_hton (&rm.amount_with_fee,
-			 &amount);
-      rm.coin_pub = *coin_pub;
-      if (GNUNET_OK !=
-          GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_WALLET_COIN_MELT,
-                                      &rm.purpose,
-                                      &sig.eddsa_signature,
-                                      &coin_pub->eddsa_pub))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      /* TODO: check that deposit fee and coin value match
-	 our expectations from /keys! */
-      add = GNUNET_YES;
-    }
-    else if (0 == strcasecmp (type,
-                              "REFUND"))
-    {
-      struct TALER_RefundRequestPS rr;
-      struct TALER_MerchantSignatureP sig;
-      struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_fixed_auto ("merchant_sig",
-                                     &sig),
-        GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
-                                     &rr.h_contract_terms),
-        GNUNET_JSON_spec_fixed_auto ("merchant_pub",
-                                     &rr.merchant),
-        GNUNET_JSON_spec_uint64 ("rtransaction_id",
-				 &rr.rtransaction_id),
-        TALER_JSON_spec_amount_nbo ("refund_fee",
-				    &rr.refund_fee),
-        GNUNET_JSON_spec_end()
-      };
-
-      if (GNUNET_OK !=
-          GNUNET_JSON_parse (transaction,
-                             spec,
-                             NULL, NULL))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      rr.purpose.size = htonl (sizeof (rr));
-      rr.purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_REFUND);
-      rr.coin_pub = *coin_pub;
-      TALER_amount_hton (&rr.refund_amount,
-			 &amount);
-      if (GNUNET_OK !=
-          GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MERCHANT_REFUND,
-                                      &rr.purpose,
-                                      &sig.eddsa_sig,
-                                      &rr.merchant.eddsa_pub))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      /* NOTE: theoretically, we could also check that the given
-         merchant_pub and h_contract_terms appear in the
-         history under deposits.  However, there is really no benefit
-         for the exchange to lie here, so not checking is probably OK
-         (an auditor ought to check, though). Then again, we similarly
-         had no reason to check the merchant's signature (other than a
-         well-formendess check). */
-      /* TODO: check that deposit fee and coin value match
-	 our expectations from /keys! */
-      add = GNUNET_NO;
-    }
-    else if (0 == strcasecmp (type,
-                              "PAYBACK"))
-    {
-      struct TALER_PaybackConfirmationPS pc;
-      struct TALER_ExchangePublicKeyP exchange_pub;
-      struct TALER_ExchangeSignatureP exchange_sig;
-      struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_fixed_auto ("exchange_sig",
-                                     &exchange_sig),
-        GNUNET_JSON_spec_fixed_auto ("exchange_pub",
-                                     &exchange_pub),
-        GNUNET_JSON_spec_fixed_auto ("reserve_pub",
-                                     &pc.reserve_pub),
-	GNUNET_JSON_spec_absolute_time_nbo ("timestamp",
-					    &pc.timestamp),
-        GNUNET_JSON_spec_end()
-      };
-
-      if (GNUNET_OK !=
-          GNUNET_JSON_parse (transaction,
-                             spec,
-                             NULL, NULL))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      pc.purpose.size = htonl (sizeof (pc));
-      pc.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_PAYBACK);
-      pc.coin_pub = *coin_pub;
-      TALER_amount_hton (&pc.payback_amount,
-			 &amount);
-      if (GNUNET_OK !=
-          GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_EXCHANGE_CONFIRM_PAYBACK,
-                                      &pc.purpose,
-                                      &exchange_sig.eddsa_signature,
-                                      &exchange_pub.eddsa_pub))
-      {
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-      add = GNUNET_YES;
-    }
-    else
-    {
-      /* signature not supported, new version on server? */
-      GNUNET_break_op (0);
-      return GNUNET_SYSERR;
-    }
-    if (GNUNET_YES == add)
-    {
-      /* This amount should be added to the total */
-      if (GNUNET_OK !=
-          TALER_amount_add (total,
-                            total,
-                            &amount))
-      {
-        /* overflow in history already!? inconceivable! Bad exchange! */
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-    }
-    else
-    {
-      /* This amount should be subtracted from the total.
-
-         However, for the implementation, we first *add* up all of
-         these negative amounts, as we might get refunds before
-         deposits from a semi-evil exchange.  Then, at the end, we do
-         the subtraction by calculating "total = total - rtotal" */
-      GNUNET_assert (GNUNET_NO == add);
-      if (GNUNET_OK !=
-          TALER_amount_add (&rtotal,
-                            &rtotal,
-                            &amount))
-      {
-        /* overflow in refund history? inconceivable! Bad exchange! */
-        GNUNET_break_op (0);
-        return GNUNET_SYSERR;
-      }
-    }
-  }
-
-  /* Finally, subtract 'rtotal' from total to handle the subtractions */
-  if (GNUNET_OK !=
-      TALER_amount_subtract (total,
-                             total,
-                             &rtotal))
-  {
-    /* underflow in history? inconceivable! Bad exchange! */
-    GNUNET_break_op (0);
-    return GNUNET_SYSERR;
-  }
-
-  return GNUNET_OK;
-}
-
-
-/* end of exchange_api_common.c */