diff --git a/include/poet/HashFunctions.hpp b/include/poet/HashFunctions.hpp
new file mode 100644
index 000000000..84ae38ed6
--- /dev/null
+++ b/include/poet/HashFunctions.hpp
@@ -0,0 +1,38 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2022 Marco De Lucia, Max Luebke (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
+#ifndef HASHFUNCTIONS_H_
+#define HASHFUNCTIONS_H_
+
+#include <cstdint>
+#include <openssl/evp.h>
+
+namespace poet {
+
+void initHashCtx(const EVP_MD *md);
+void freeHashCtx();
+
+uint64_t hashDHT(int key_size, void *key);
+
+
+
+}
+
+#endif // HASHFUNCTIONS_H_
diff --git a/src/DHT_Wrapper.cpp b/src/DHT_Wrapper.cpp
index 3f398e552..988d409af 100644
--- a/src/DHT_Wrapper.cpp
+++ b/src/DHT_Wrapper.cpp
@@ -18,39 +18,26 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
+#include "poet/HashFunctions.hpp"
+#include <cstddef>
+#include <cstdint>
+#include <openssl/evp.h>
 #include <poet/DHT_Wrapper.hpp>
 
 #include <math.h>
-#include <openssl/md5.h>
 
 #include <iostream>
+#include <stdexcept>
 
 using namespace poet;
 using namespace std;
 
-uint64_t poet::get_md5(int key_size, void *key) {
-  MD5_CTX ctx;
-  unsigned char sum[MD5_DIGEST_LENGTH];
-  uint64_t retval, *v1, *v2;
-
-  // calculate md5 using MD5 functions
-  MD5_Init(&ctx);
-  MD5_Update(&ctx, key, key_size);
-  MD5_Final(sum, &ctx);
-
-  // divide hash in 2 64 bit parts and XOR them
-  v1 = (uint64_t *)&sum[0];
-  v2 = (uint64_t *)&sum[8];
-  retval = *v1 ^ *v2;
-
-  return retval;
-}
-
 DHT_Wrapper::DHT_Wrapper(SimParams &params, MPI_Comm dht_comm,
                          int buckets_per_process, int data_size, int key_size) {
+  poet::initHashCtx(EVP_md5());
   // initialize DHT object
-  dht_object =
-      DHT_create(dht_comm, buckets_per_process, data_size, key_size, &get_md5);
+  dht_object = DHT_create(dht_comm, buckets_per_process, data_size, key_size,
+                          &poet::hashDHT);
   // allocate memory for fuzzing buffer
   fuzzing_buffer = (double *)malloc(key_size);
 
@@ -69,6 +56,7 @@ DHT_Wrapper::~DHT_Wrapper() {
   DHT_free(dht_object, NULL, NULL);
   // free fuzzing buffer
   free(fuzzing_buffer);
+  poet::freeHashCtx();
 }
 
 void DHT_Wrapper::checkDHT(int length, std::vector<bool> &out_result_index,
@@ -149,7 +137,8 @@ int DHT_Wrapper::tableToFile(const char *filename) {
 
 int DHT_Wrapper::fileToTable(const char *filename) {
   int res = DHT_from_file(dht_object, filename);
-  if (res != DHT_SUCCESS) return res;
+  if (res != DHT_SUCCESS)
+    return res;
 
 #ifdef DHT_STATISTICS
   DHT_print_statistics(dht_object);
@@ -228,5 +217,6 @@ void DHT_Wrapper::fuzzForDHT(int var_count, void *key, double dt) {
   }
   // if timestep differs over iterations set current current time step at the
   // end of fuzzing buffer
-  if (dt_differ) fuzzing_buffer[var_count] = dt;
+  if (dt_differ)
+    fuzzing_buffer[var_count] = dt;
 }
diff --git a/src/HashFunctions.cpp b/src/HashFunctions.cpp
new file mode 100644
index 000000000..ee6393e14
--- /dev/null
+++ b/src/HashFunctions.cpp
@@ -0,0 +1,62 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2022 Marco De Lucia, Max Luebke (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
+#include "poet/HashFunctions.hpp"
+
+#include <cstddef>
+#include <openssl/evp.h>
+#include <openssl/md5.h>
+#include <stdexcept>
+
+// HACK: I know this is not a good practice, but this will do it for now!
+EVP_MD_CTX *ctx = NULL;
+
+void poet::initHashCtx(const EVP_MD *md) {
+  if (ctx == NULL) {
+    ctx = EVP_MD_CTX_new();
+    EVP_DigestInit_ex(ctx, md, NULL);
+  }
+}
+
+void poet::freeHashCtx() {
+  EVP_MD_CTX_free(ctx);
+  ctx = NULL;
+}
+
+uint64_t poet::hashDHT(int key_size, void *key) {
+  unsigned char sum[MD5_DIGEST_LENGTH];
+  uint32_t md_len;
+  uint64_t retval, *v1, *v2;
+
+  // calculate md5 using MD5 functions
+  EVP_DigestUpdate(ctx, key, key_size);
+  EVP_DigestFinal_ex(ctx, sum, &md_len);
+
+  if (md_len != MD5_DIGEST_LENGTH) {
+    throw std::runtime_error("Something went wrong during MD5 hashing!");
+  }
+
+  // divide hash in 2 64 bit parts and XOR them
+  v1 = (uint64_t *)&sum[0];
+  v2 = (uint64_t *)&sum[8];
+  retval = *v1 ^ *v2;
+
+  return retval;
+}