diff --git a/sink/.gitignore b/sink/.gitignore
deleted file mode 100644
index 567609b..0000000
--- a/sink/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-build/
diff --git a/sink/Makefile b/sink/Makefile
deleted file mode 100644
index afb71a0..0000000
--- a/sink/Makefile
+++ /dev/null
@@ -1,42 +0,0 @@
-BUILD_DIR = build
-
-C_SOURCES = \
-../cube/User/Src/sha256.c \
-sink20169.c \
-logging.c
-
-
-C_INCLUDES = \
--I. \
--I../cube/User/Inc
-
-VERSION := $(shell git rev-parse --short=8 HEAD)
-
-CC = gcc
-CFLAGS = $(C_INCLUDES) -Wall -Werror -std=c99 -DVERSION="\"$(VERSION)\""
-LDFLAGS = -lconfig -lcurl
-TARGET = sink20169
-
-UNAME_S := $(shell uname -s)
-ifeq ($(UNAME_S),OpenBSD)
-  CFLAGS += -I/usr/local/include -DOpenBSD=1
-  LDFLAGS += -L/usr/local/lib
-endif
-
-all: $(BUILD_DIR)/$(TARGET)
-
-OBJECTS = $(addprefix $(BUILD_DIR)/,$(notdir $(C_SOURCES:.c=.o)))
-vpath %.c $(sort $(dir $(C_SOURCES)))
-
-$(BUILD_DIR)/%.o: %.c Makefile | $(BUILD_DIR)
-	$(CC) -c $(CFLAGS) $< -o $@
-
-$(BUILD_DIR)/$(TARGET): $(OBJECTS) Makefile
-	$(CC) $(OBJECTS) $(LDFLAGS) -o $@
-
-$(BUILD_DIR):
-	mkdir $@
-
-.phony: clean
-clean:
-	-rm -rf $(BUILD_DIR)
diff --git a/sink/logging.c b/sink/logging.c
deleted file mode 100644
index e1d4e4f..0000000
--- a/sink/logging.c
+++ /dev/null
@@ -1,53 +0,0 @@
-#define _DEFAULT_SOURCE
-
-#include <syslog.h>
-#include <stdarg.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <string.h>
-
-extern bool verbose;
-int facility = LOG_LOCAL0;
-
-void setfacility(const char *facility_p) {
-  if (! strcmp(facility_p, "LOCAL0")) {
-    facility = LOG_LOCAL0;
-  } else if (! strcmp(facility_p, "LOCAL1")) {
-    facility = LOG_LOCAL1;
-  } else if (! strcmp(facility_p, "LOCAL2")) {
-    facility = LOG_LOCAL2;
-  } else if (! strcmp(facility_p, "LOCAL3")) {
-    facility = LOG_LOCAL3;
-  } else if (! strcmp(facility_p, "LOCAL4")) {
-    facility = LOG_LOCAL4;
-  } else if (! strcmp(facility_p, "LOCAL5")) {
-    facility = LOG_LOCAL5;
-  } else if (! strcmp(facility_p, "LOCAL6")) {
-    facility = LOG_LOCAL6;
-  } else if (! strcmp(facility_p, "LOCAL7")) {
-    facility = LOG_LOCAL7;
-  } else if (! strcmp(facility_p, "USER")) {
-    facility = LOG_USER;
-  } else if (! strcmp(facility_p, "DAEMON")) {
-    facility = LOG_DAEMON;
-  }
-}
-
-
-void logmsg(int prio, const char* format, ...) {
-  va_list vl;
-  char buf[1024];
-
-  va_start(vl, format);
-  vsnprintf(buf, sizeof(buf), format, vl);
-  va_end(vl);
-
-  if (verbose) {
-    printf("%s\n", buf);
-  }
-
-  openlog("counter", 0, facility);
-  syslog(prio, "%s", buf);
-  closelog();
-}
-
diff --git a/sink/logging.h b/sink/logging.h
deleted file mode 100644
index 12d34b2..0000000
--- a/sink/logging.h
+++ /dev/null
@@ -1,8 +0,0 @@
-#ifndef _LOGGING_H_
-#define _LOGGING_H_
-
-#include <syslog.h>
-
-void logmsg(int prio, const char* format, ...);
-void setfacility(const char *facility_p);
-#endif // _LOGGING_H_
diff --git a/sink/readme.md b/sink/readme.md
deleted file mode 100644
index b711bdd..0000000
--- a/sink/readme.md
+++ /dev/null
@@ -1,3 +0,0 @@
-Make sure libconfig and libcurl are available.
-On Linux (Debian) install libconfig-dev and libcurl4-openssl-dev,
-on OpenBSD install libconfig and curl.
diff --git a/sink/sink20169.c b/sink/sink20169.c
deleted file mode 100644
index 18940b2..0000000
--- a/sink/sink20169.c
+++ /dev/null
@@ -1,431 +0,0 @@
-#define _DEFAULT_SOURCE
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdbool.h>
-#include <unistd.h>
-#include <errno.h>
-#include <sys/socket.h>
-#include <sys/types.h>
-#include <netinet/in.h>
-#include <string.h>
-#include <getopt.h>
-#include <pwd.h>
-
-#include <libconfig.h>
-#include <curl/curl.h>
-
-#include <sinkStruct.h>
-#include <logging.h>
-#include <sha256.h>
-
-
-const char DEFAULT_CONFIG_FILENAME[] = "./sink20169.cfg";
-
-typedef struct {
-    const char *deviceId;
-    const char *location;
-    const char *sharedSecret;
-} t_device;
-
-typedef struct {
-    config_t cfg;
-    uint16_t numOfDevices;
-    t_device *devices;    
-} t_configHandle;
-
-typedef struct {
-    t_configHandle *configHandle;
-    int receiveSockFd;
-} t_receiverHandle;
-
-typedef struct {
-    t_configHandle *configHandle;
-    const char *influxUser;
-    const char *influxPass;
-    const char *influxServer;
-    uint16_t influxPort;
-    const char *influxDatabase;
-    const char *influxMeasurement;
-    char influxUrl[1024];
-} t_forwarderHandle;
-
-bool verbose = false;
-
-
-int initConfig(const char *configFilename, t_configHandle *configHandle) {
-    configHandle->numOfDevices = 0;
-    configHandle->devices = NULL;
-
-    config_init(&(configHandle->cfg));
-    if (! config_read_file(&(configHandle->cfg), configFilename)) {
-        logmsg(LOG_ERR, "failed to read config file: %s:%d - %s\n",
-            config_error_file(&(configHandle->cfg)), config_error_line(&(configHandle->cfg)),
-            config_error_text(&(configHandle->cfg)));
-        config_destroy(&(configHandle->cfg));
-        return -1;
-    }
-
-    config_setting_t *devicesConfig = config_lookup(&(configHandle->cfg), "devices");
-    if (devicesConfig == NULL) {
-        logmsg(LOG_ERR, "receiver: no devices configuration found");
-        return -2;
-    }
-    configHandle->numOfDevices = config_setting_length(devicesConfig);
-    configHandle->devices = (t_device*) malloc(configHandle->numOfDevices * sizeof(t_device));
-    for (uint16_t i = 0; i < configHandle->numOfDevices; i++) {
-        config_setting_t *deviceConfig = config_setting_get_elem(devicesConfig, i);
-        if (! config_setting_lookup_string(deviceConfig, "deviceId", &(configHandle->devices[i].deviceId))) {
-            logmsg(LOG_ERR, "no deviceId for device %d", i);
-            return -3;
-        }
-        if (! config_setting_lookup_string(deviceConfig, "location", &(configHandle->devices[i].location))) {
-            logmsg(LOG_ERR, "no location for device %d", i);
-            return -4;
-        }
-        if (! config_setting_lookup_string(deviceConfig, "sharedSecret", &(configHandle->devices[i].sharedSecret))) {
-            logmsg(LOG_ERR, "no sharedSecret for device %d", i);
-            return -5;
-        }
-        if (strlen(configHandle->devices[i].sharedSecret) >= SHA256_BLOCK_SIZE) {
-            logmsg(LOG_ERR, "Configured sharedsecret for device %d is too long", i);
-            return -6;
-        }
-        logmsg(LOG_INFO, "Device loaded: %d %s %s %s", i, 
-               configHandle->devices[i].deviceId, 
-               configHandle->devices[i].location, 
-               configHandle->devices[i].sharedSecret);
-    }
-
-    return 0;
-}
-
-void deinitConfig(t_configHandle *configHandle) {
-    config_destroy(&(configHandle->cfg));
-    if (configHandle->devices) {
-        free(configHandle->devices);
-        configHandle->devices = NULL;
-    }
-}
-
-t_device *findDevice(t_configHandle *configHandle, char *deviceId) {
-    for (uint16_t i = 0; i < configHandle->numOfDevices; i++) {
-        if (! strncmp(configHandle->devices[i].deviceId, deviceId, strlen(configHandle->devices[i].deviceId))) {
-            return &(configHandle->devices[i]);
-        }
-    }
-    return NULL;
-}
-
-int initReceiver(t_configHandle *configHandle, t_receiverHandle *handle) {
-    handle->configHandle = configHandle;
-
-    struct sockaddr_in servaddr;
-
-    handle->receiveSockFd = socket(AF_INET, SOCK_DGRAM, 0);
-    if (handle->receiveSockFd == -1) {
-        logmsg(LOG_ERR, "failed to create receive socket: %d", errno);
-        return -1;
-    }
-
-    int receivePort = 20169;
-    config_lookup_int(&(configHandle->cfg), "receivePort", &receivePort);
-    if (receivePort < 1 || receivePort > 65535) {
-        logmsg(LOG_ERR, "illegal receive port configured");
-        return -2;
-    }
-
-    memset(&servaddr, 0, sizeof(servaddr));
-    servaddr.sin_family = AF_INET;
-    servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
-    servaddr.sin_port = htons(receivePort);
-
-    if (-1 == bind(handle->receiveSockFd, (const struct sockaddr *) &servaddr, sizeof(servaddr))) {
-        logmsg(LOG_ERR, "unable to bind receive: %d", errno);
-        return -3;
-    }
-    return 0;
-}
-
-void deinitReceiver(t_receiverHandle *handle) {
-    close(handle->receiveSockFd);
-}
-
-int receiveAndVerifyMinuteBuffer(t_receiverHandle *handle, t_minuteBuffer *buf) {
-    struct sockaddr_in cliaddr;
-    socklen_t cliaddrlen = sizeof(cliaddr);
-
-    int n = recvfrom(handle->receiveSockFd, buf->b, sizeof(buf->b), MSG_TRUNC,
-                     (struct sockaddr *) &cliaddr, &cliaddrlen);
-    logmsg(LOG_INFO, "received %d octets from %d.%d.%d.%d", 
-           n, 
-           (cliaddr.sin_addr.s_addr & 0x0ff), 
-           ((cliaddr.sin_addr.s_addr >> 8) & 0x0ff), 
-           ((cliaddr.sin_addr.s_addr >> 16) & 0x0ff), 
-           ((cliaddr.sin_addr.s_addr >> 24) & 0x0ff));
-
-    if (n != sizeof(buf->b)) {
-        logmsg(LOG_ERR, "Illegal packet size: %d", n);
-        return -1;
-    }
-
-    t_device *device = findDevice(handle->configHandle, buf->s.deviceId);    
-    if (device == NULL) {
-        logmsg(LOG_ERR, "unknown device");
-        return -7;
-    }
-    const char *sharedSecret = device->sharedSecret;
-
-    uint8_t receivedHash[SHA256_BLOCK_SIZE];
-    memcpy(receivedHash, buf->s.hash, SHA256_BLOCK_SIZE);
-    memcpy(buf->s.hash, sharedSecret, SHA256_BLOCK_SIZE);
-
-    SHA256_CTX ctx;
-    uint8_t calculatedHash[SHA256_BLOCK_SIZE];
-    sha256_init(&ctx);
-    sha256_update(&ctx, buf->b, sizeof(buf->b));
-    sha256_final(&ctx, calculatedHash);
-
-    if (memcmp(receivedHash, calculatedHash, SHA256_BLOCK_SIZE) != 0) {
-        logmsg(LOG_ERR, "Invalid hash in msg for device %s", buf->s.deviceId);
-        return -5;
-    }
-
-    return 0;
-}
-
-
-int initForwarder(t_configHandle *configHandle, t_forwarderHandle *handle) {
-    handle->configHandle = configHandle;
-
-    handle->influxUser = NULL;
-    handle->influxPass = NULL;
-    handle->influxServer = NULL;
-    handle->influxDatabase = NULL;
-    handle->influxMeasurement = NULL;
-
-    config_lookup_string(&(configHandle->cfg), "influxUser", &(handle->influxUser));
-    config_lookup_string(&(configHandle->cfg), "influxPass", &(handle->influxPass));
-    config_lookup_string(&(configHandle->cfg), "influxServer", &(handle->influxServer));
-    config_lookup_string(&(configHandle->cfg), "influxDatabase", &(handle->influxDatabase));
-    config_lookup_string(&(configHandle->cfg), "influxMeasurement", &(handle->influxMeasurement));
-
-    int influxPort = 8086;
-    config_lookup_int(&(configHandle->cfg), "influxPort", &influxPort);
-    if (influxPort < 1 || influxPort > 65535) {
-        logmsg(LOG_ERR, "illegal influx port configured");
-        return -2;
-    }
-    handle->influxPort = influxPort;
-
-    if (! handle->influxServer) {
-        logmsg(LOG_ERR, "no influxServer configured");
-        return -1;
-    }
-    if (! handle->influxDatabase) {
-        logmsg(LOG_ERR, "no influxDatabase configured");
-        return -2;
-    }
-    if (! handle->influxMeasurement) {
-        logmsg(LOG_ERR, "no influxMeasurement configured");
-        return -3;
-    }
-
-    int res = snprintf(handle->influxUrl, sizeof(handle->influxUrl),
-                       "http://%s:%d/write?db=%s&precision=s",
-                       handle->influxServer, handle->influxPort, handle->influxDatabase);
-    if (res > sizeof(handle->influxUrl)) {
-        logmsg(LOG_ERR, "influxUrl has not enough space");
-        return -4;
-    }
-    logmsg(LOG_INFO, "influxUrl is %s", handle->influxUrl);
-
-    return 0;
-}
-
-void deinitForwarder(t_forwarderHandle *handle) {
-
-}
-
-int httpPostRequest(char *url, const char *user, const char *pass, char *payload) {
-    CURL *curl = curl_easy_init();
-    if (! curl) {
-        logmsg(LOG_ERR, "error instantiating curl");
-        return -1;
-    }
-
-    curl_easy_setopt(curl, CURLOPT_URL, url);
-    if (user && pass) {
-        curl_easy_setopt(curl, CURLOPT_HTTPAUTH, CURLAUTH_DIGEST);
-        curl_easy_setopt(curl, CURLOPT_USERNAME, user);
-        curl_easy_setopt(curl, CURLOPT_PASSWORD, pass);
-    }
-    curl_easy_setopt(curl, CURLOPT_POSTFIELDS, payload);
-
-    CURLcode res = curl_easy_perform(curl);
-    if (res != CURLE_OK) {
-        logmsg(LOG_ERR, "post request failed: %s", curl_easy_strerror(res));
-        return -2;
-    }
-
-    curl_easy_cleanup(curl);
-
-    return 0;
-}
-
-int forwardMinuteBuffer(t_forwarderHandle *handle, t_minuteBuffer *buf) {
-    logmsg(LOG_INFO, "D: %s, R: %u, P: %u, W: %u, V: %08x", 
-           buf->s.deviceId, buf->s.totalRunningHours, buf->s.totalPowercycles, buf->s.totalWatchdogResets,
-           buf->s.version);
-           
-    t_device *device = findDevice(handle->configHandle, buf->s.deviceId);
-    if (device == NULL) {
-        logmsg(LOG_ERR, "unknown device, strange, should not happen here");
-        return -2;
-    }
-    const char *location = device->location;
-
-    for (uint8_t j = 0; j < SECONDS_PER_MINUTE; j++) {
-        uint64_t timestamp = buf->s.timestamp + j;
-        logmsg(LOG_DEBUG, "Time: %lu, Frequency: %u", timestamp, buf->s.frequency[j]);
-
-        int frequency_before_point = buf->s.frequency[j] / 1000;
-        int frequency_behind_point = buf->s.frequency[j] - (frequency_before_point * 1000);
-
-        char payload[256];
-        int res = snprintf(payload, sizeof(payload),
-                           "%s,valid=1,location=%s,host=%s freq=%d.%03d"
-#ifdef OpenBSD
-                           " %llu"
-#else
-                           " %lu"
-#endif                                                      
-                           "",
-                           handle->influxMeasurement, location, buf->s.deviceId, 
-                           frequency_before_point, frequency_behind_point, 
-                           timestamp);
-        if (res > sizeof(payload)) {
-            logmsg(LOG_ERR, "payload buffer to small");
-            return -1;
-        }
-        logmsg(LOG_DEBUG, "Payload: %s", payload);
-        res = httpPostRequest(handle->influxUrl, handle->influxUser, handle->influxPass, payload);
-        if (res == 0) {
-            logmsg(LOG_DEBUG, "Successfully sent to InfluxDB");
-        }
-    }
-
-    logmsg(LOG_INFO, "Successfully sent whole minute to InfluxDB");
-    return 0;
-}
-
-void usage() {
-    printf("sinkserver for mainsfrequency counter\n");
-    printf("https://home.hottis.de/gitlab/wolutator/mains-frequency-counter-stm32\n");
-    printf("Version: " VERSION "\n");
-    printf("\nUsage\n");
-    printf("  -f FILENAME R..... Config file to be used\n");
-    printf("  -v ............... Verbose, writes all logging on stdout too\n");
-    printf("  -s FACILITY ...... Sets syslog facility, only LOCAL[0..7]\n");
-    printf("                     USER and DAEMON are supported\n");
-    printf("  -n USER .......... If started as root drop privileges and become\n");
-    printf("                     USER\n");
-    printf("  -b ............... fork into background\n");
-    printf("  -h ............... This help\n");
-}
-
-int main(int argc, char **argv) {
-    t_configHandle configHandle;
-    t_forwarderHandle forwarderHandle;
-    t_receiverHandle receiverHandle;
-
-
-    const char *configFilename = DEFAULT_CONFIG_FILENAME;
-    const char *dropPrivilegesToUser = NULL;
-    bool doFork = false;
-
-    int c;
-    while ((c = getopt(argc, argv, "f:vs:hn:b")) != -1) {
-        switch (c) {
-            case 'f':
-                configFilename = strdup(optarg);
-                break;
-            case 'v':
-                verbose = true;
-                break;
-            case 's':
-                setfacility(optarg);
-                break;
-            case 'n':
-                dropPrivilegesToUser = strdup(optarg);
-                break;
-            case 'b':
-                doFork = true;
-                break;
-            case 'h':
-                usage();
-                exit(0);
-                break;
-        }
-    }
-
-    if ((getuid() == 0) && (dropPrivilegesToUser != NULL)) {
-        logmsg(LOG_INFO, "dropping root privileges, become %s", dropPrivilegesToUser);
-        struct passwd *userEntry = getpwnam(dropPrivilegesToUser);
-        if (userEntry == NULL) {
-            logmsg(LOG_ERR, "can not find entry for user %s", dropPrivilegesToUser);
-            exit(1);
-        }        
-
-        if (setuid(userEntry->pw_uid) != 0) {
-            logmsg(LOG_ERR, "unable to drop root privileges to %d", userEntry->pw_uid);
-            exit(2);
-        }
-    }
-
-    if (0 != initConfig(configFilename, &configHandle)) {
-        logmsg(LOG_ERR, "error when reading configuration");
-        exit(3);
-    }
-    
-    if (doFork) {
-        int pid = fork();
-        if (pid == -1) {
-            logmsg(LOG_ERR, "error when forking into background: %d", errno);
-            exit(4);
-        }
-        if (pid != 0) {
-            logmsg(LOG_INFO, "successfully forking into background, child's pid is %d", pid);
-            exit(0);
-        }
-    }
-
-    if (0 != initReceiver(&configHandle, &receiverHandle)) {
-        logmsg(LOG_ERR, "error when initializing receiver");
-        exit(5);
-    }
-
-    if (0 != initForwarder(&configHandle, &forwarderHandle)) {
-        logmsg(LOG_ERR, "error when initializing forwarder");
-        exit(6);
-    }
-
-
-    while (1) {
-        t_minuteBuffer buf;
-        
-        if (receiveAndVerifyMinuteBuffer(&receiverHandle, &buf) < 0) {
-            logmsg(LOG_ERR, "error in receiveAndVerify");
-            continue;
-        }
-
-        if (forwardMinuteBuffer(&forwarderHandle, &buf) < 0) {
-            logmsg(LOG_ERR, "error in send");
-        }
-    }
-
-
-    deinitForwarder(&forwarderHandle);
-    deinitReceiver(&receiverHandle);
-    deinitConfig(&configHandle);
-}
diff --git a/sink/sink20169.cfg b/sink/sink20169.cfg
deleted file mode 100644
index 3130de4..0000000
--- a/sink/sink20169.cfg
+++ /dev/null
@@ -1,18 +0,0 @@
-// influxUser = "";
-// influxPass = "";
-influxServer = "172.16.10.16";
-influxPort = 8086;
-influxDatabase = "smarthome2";
-influxMeasurement = "mainsfrequency";
-
-receivePort = 20169;
-
-devices = (
-    {
-        deviceId = "MainsCnt01";
-        // sharedSecret must have exactly 31 characters
-        sharedSecret = "Uj6*uKDp@8Kvfa4g5eRMLUfVsSuqjxW";
-        // location must neither contains spaces nor commas or any other URL-special characters
-        location = "Essen_DE";
-    }
-);