diff --git a/.gitignore b/.gitignore
index 948ddaec..ed26bf95 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,4 +12,3 @@ test/test.log
 test/acceptance/oauth/venv/*
 coverage/
 npm-debug.log
-libredis_cell.so
diff --git a/app/middlewares/rate-limit.js b/app/middlewares/rate-limit.js
index 199bfcfa..3e4d2f47 100644
--- a/app/middlewares/rate-limit.js
+++ b/app/middlewares/rate-limit.js
@@ -29,12 +29,16 @@ function rateLimit(userLimits, endpointGroup = null) {
             res.set({
                 'Carto-Rate-Limit-Limit': limit,
                 'Carto-Rate-Limit-Remaining': remaining,
-                'Retry-After': retry,
                 'Carto-Rate-Limit-Reset': reset
             });
     
             if (isBlocked) {
-                const rateLimitError = new Error('You are over the limits.');
+                // retry is floor rounded in seconds by redis-cell
+                res.set('Retry-After', retry + 1);
+                
+                const rateLimitError = new Error(
+                    'You are over platform\'s limits. Please contact us to know more details'
+                );
                 rateLimitError.http_status = 429;
                 rateLimitError.context = 'limit';
                 rateLimitError.detail = 'rate-limit';
diff --git a/test/acceptance/rate-limit.js b/test/acceptance/rate-limit.js
index a68d5257..e78401bf 100644
--- a/test/acceptance/rate-limit.js
+++ b/test/acceptance/rate-limit.js
@@ -48,7 +48,10 @@ function assertRequest (status, limit, remaining, reset, retry, done = null) {
             assert.equal(res.headers['carto-rate-limit-limit'], limit);
             assert.equal(res.headers['carto-rate-limit-remaining'], remaining);
             assert.equal(res.headers['carto-rate-limit-reset'], reset);
-            assert.equal(res.headers['retry-after'], retry);
+
+            if (retry) {
+                assert.equal(res.headers['retry-after'], retry);
+            }
 
             if(status === 429) { 
                 const expectedResponse = { 
@@ -91,12 +94,12 @@ describe('rate limit', function() {
     });
 
     it("1 req/sec: 2 req/seg should be limited", function(done) {
-        assertRequest(200, 2, 1, 1, -1);  
-        setTimeout( () => assertRequest(200, 2, 0, 1, -1), 250 );
-        setTimeout( () => assertRequest(429, 2, 0, 1, 0),  500 );
-        setTimeout( () => assertRequest(429, 2, 0, 1, 0),  750 );
-        setTimeout( () => assertRequest(429, 2, 0, 1, 0),  950 );
-        setTimeout( () => assertRequest(200, 2, 0, 1, -1, done), 1050 );
+        assertRequest(200, 2, 1, 1);  
+        setTimeout( () => assertRequest(200, 2, 0, 1, null), 250 );
+        setTimeout( () => assertRequest(429, 2, 0, 1, 1),  500 );
+        setTimeout( () => assertRequest(429, 2, 0, 1, 1),  750 );
+        setTimeout( () => assertRequest(429, 2, 0, 1, 1),  950 );
+        setTimeout( () => assertRequest(200, 2, 0, 1, null, done), 1050 );
     });
 
 });
diff --git a/test/run_tests.sh b/test/run_tests.sh
index db030305..c3f2cb67 100755
--- a/test/run_tests.sh
+++ b/test/run_tests.sh
@@ -18,7 +18,6 @@ OPT_DROP_PGSQL=yes   # drop the postgreql test environment
 OPT_DROP_REDIS=yes   # drop the redis test environment
 OPT_COVERAGE=no      # run tests with coverage
 OPT_OFFLINE=no       # do not donwload scripts
-OPT_REDIS_CELL=yes   # download redis cell
 
 
 cd $(dirname $0)
@@ -55,17 +54,6 @@ die() {
 	exit 1
 }
 
-get_redis_cell() {
-  if test x"$OPT_REDIS_CELL" = xyes; then
-    echo "Downloading redis-cell"
-    curl -L https://github.com/brandur/redis-cell/releases/download/v0.2.2/redis-cell-v0.2.2-x86_64-unknown-linux-gnu.tar.gz --output redis-cell.tar.gz > /dev/null 2>&1
-    tar xvzf redis-cell.tar.gz > /dev/null 2>&1
-    mv libredis_cell.so ${BASEDIR}/support/libredis_cell.so
-    rm redis-cell.tar.gz
-    rm libredis_cell.d
-  fi
-}
-
 trap 'cleanup_and_exit' 1 2 3 5 9 13
 
 while [ -n "$1" ]; do
@@ -103,10 +91,6 @@ while [ -n "$1" ]; do
                 OPT_OFFLINE=yes
                 shift
                 continue
-        elif test "$1" = "--norediscell"; then
-                OPT_REDIS_CELL=no
-                shift
-                continue
         else
                 break
         fi
@@ -128,9 +112,12 @@ fi
 TESTS=$@
 
 if test x"$OPT_CREATE_REDIS" = xyes; then
-  get_redis_cell
   echo "Starting redis on port ${REDIS_PORT}"
-  echo "port ${REDIS_PORT}" | redis-server - --loadmodule ${BASEDIR}/support/libredis_cell.so > ${BASEDIR}/test.log &
+  REDIS_CELL_PATH="${BASEDIR}/support/libredis_cell.so"
+  if [[ "$OSTYPE" == "darwin"* ]]; then
+    REDIS_CELL_PATH="${BASEDIR}/support/libredis_cell.dylib"
+  fi
+  echo "port ${REDIS_PORT}" | redis-server - --loadmodule ${REDIS_CELL_PATH} > ${BASEDIR}/test.log &
   PID_REDIS=$!
   echo ${PID_REDIS} > ${BASEDIR}/redis.pid
 fi
diff --git a/test/support/libredis_cell.dylib b/test/support/libredis_cell.dylib
new file mode 100755
index 00000000..7c7d6c88
Binary files /dev/null and b/test/support/libredis_cell.dylib differ
diff --git a/test/support/libredis_cell.so b/test/support/libredis_cell.so
new file mode 100755
index 00000000..1da8aa66
Binary files /dev/null and b/test/support/libredis_cell.so differ