--- a/toolkit/components/telemetry/pingsender/pingsender_unix_common.cpp
+++ b/toolkit/components/telemetry/pingsender/pingsender_unix_common.cpp
@@ -7,20 +7,24 @@
 #include <cstring>
 #include <string>
 
 #include <dlfcn.h>
 #include <unistd.h>
 
 #include "third_party/curl/curl.h"
 
+#include "mozilla/Unused.h"
+
 namespace PingSender {
 
 using std::string;
 
+using mozilla::Unused;
+
 /**
  * A simple wrapper around libcurl "easy" functions. Provides RAII opening
  * and initialization of the curl library
  */
 class CurlWrapper
 {
 public:
   CurlWrapper();
@@ -130,21 +134,33 @@ CurlWrapper::Init()
   if (!mCurl) {
     PINGSENDER_LOG("ERROR: Could not initialize libcurl\n");
     return false;
   }
 
   return true;
 }
 
+static size_t
+DummyWriteCallback(char *ptr, size_t size, size_t nmemb, void *userdata)
+{
+  Unused << ptr;
+  Unused << size;
+  Unused << nmemb;
+  Unused << userdata;
+
+  return size * nmemb;
+}
+
 bool
 CurlWrapper::Post(const string& url, const string& payload)
 {
   easy_setopt(mCurl, CURLOPT_URL, url.c_str());
   easy_setopt(mCurl, CURLOPT_USERAGENT, kUserAgent);
+  easy_setopt(mCurl, CURLOPT_WRITEFUNCTION, DummyWriteCallback);
 
   // Build the date header.
   std::string dateHeader = GenerateDateHeader();
 
   // Set the custom headers.
   curl_slist* headerChunk = nullptr;
   headerChunk = slist_append(headerChunk, kCustomVersionHeader);
   headerChunk = slist_append(headerChunk, kContentEncodingHeader);