diff --git a/DESCRIPTION b/DESCRIPTION
index 45375b9..abb258f 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -14,9 +14,10 @@ BugReports: https://github.com/dselivanov/LSHR/issues
 VignetteBuilder: knitr
 SystemRequirements: C++11
 Depends:
-    Matrix,
     methods
 Imports:
+    Matrix,
+    bit64,
     data.table(>= 1.9.10),
     magrittr (>= 1.5),
     Rcpp (>= 0.10.3),
diff --git a/NAMESPACE b/NAMESPACE
index 7a96e8b..c3b1ad8 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -9,6 +9,7 @@ import(futile.logger)
 import(magrittr)
 import(methods)
 importFrom(Rcpp,evalCpp)
+importFrom(bit64,integer64)
 importFrom(ggplot2,aes)
 importFrom(ggplot2,geom_line)
 importFrom(ggplot2,ggplot)
diff --git a/R/LSHR.R b/R/LSHR.R
index ba17116..57603d6 100644
--- a/R/LSHR.R
+++ b/R/LSHR.R
@@ -7,6 +7,7 @@
 #' @import magrittr
 #' @import methods
 #' @import Matrix
+#' @importFrom bit64 integer64
 #' @import futile.logger
 #' @importFrom Rcpp evalCpp
 #' @importFrom ggplot2 ggplot geom_line aes scale_color_discrete
diff --git a/R/RcppExports.R b/R/RcppExports.R
index c1ab7c8..6226e65 100644
--- a/R/RcppExports.R
+++ b/R/RcppExports.R
@@ -2,26 +2,26 @@
 # Generator token: 10BE3573-1514-4C36-9D1C-5A225CD40393
 
 hashfun_1 <- function(vec) {
-    .Call('LSHR_hashfun_1', PACKAGE = 'LSHR', vec)
+    .Call('_LSHR_hashfun_1', PACKAGE = 'LSHR', vec)
 }
 
 hashfun_2 <- function(vec) {
-    .Call('LSHR_hashfun_2', PACKAGE = 'LSHR', vec)
+    .Call('_LSHR_hashfun_2', PACKAGE = 'LSHR', vec)
 }
 
 get_minhash_matrix <- function(unique_shingles_length, hashfun_number, seed) {
-    .Call('LSHR_get_minhash_matrix', PACKAGE = 'LSHR', unique_shingles_length, hashfun_number, seed)
+    .Call('_LSHR_get_minhash_matrix', PACKAGE = 'LSHR', unique_shingles_length, hashfun_number, seed)
 }
 
 sign_bit <- function(x) {
-    .Call('LSHR_sign_bit', PACKAGE = 'LSHR', x)
+    .Call('_LSHR_sign_bit', PACKAGE = 'LSHR', x)
 }
 
 hash_signatures <- function(m, bands_number, rows_per_band) {
-    .Call('LSHR_hash_signatures', PACKAGE = 'LSHR', m, bands_number, rows_per_band)
+    .Call('_LSHR_hash_signatures', PACKAGE = 'LSHR', m, bands_number, rows_per_band)
 }
 
 project_spmat <- function(m, n, hash_fun_id_offest, n_threads = 0L) {
-    .Call('LSHR_project_spmat', PACKAGE = 'LSHR', m, n, hash_fun_id_offest, n_threads)
+    .Call('_LSHR_project_spmat', PACKAGE = 'LSHR', m, n, hash_fun_id_offest, n_threads)
 }
 
diff --git a/R/cosine.R b/R/cosine.R
index 223ab44..450453f 100644
--- a/R/cosine.R
+++ b/R/cosine.R
@@ -13,8 +13,8 @@
 get_similar_pairs_cosine <- function(X, bands_number, rows_per_band, seed = 1L, verbose = FALSE,
                                      mc.cores = 1, n_band_join = bands_number, ...) {
   lsh_start = Sys.time()
-  PACK_BITS = 32L
-  stopifnot(rows_per_band <= 32L)
+  PACK_BITS = 64L
+  stopifnot(rows_per_band <= PACK_BITS)
 
   if(inherits(X, "sparseMatrix"))
     if(!inherits(X, "dgRMatrix")) {
diff --git a/src/RcppExports.cpp b/src/RcppExports.cpp
index 5fda54c..60e1024 100644
--- a/src/RcppExports.cpp
+++ b/src/RcppExports.cpp
@@ -7,7 +7,7 @@ using namespace Rcpp;
 
 // hashfun_1
 Rcpp::IntegerVector hashfun_1(IntegerVector vec);
-RcppExport SEXP LSHR_hashfun_1(SEXP vecSEXP) {
+RcppExport SEXP _LSHR_hashfun_1(SEXP vecSEXP) {
 BEGIN_RCPP
     Rcpp::RObject rcpp_result_gen;
     Rcpp::RNGScope rcpp_rngScope_gen;
@@ -18,7 +18,7 @@ END_RCPP
 }
 // hashfun_2
 Rcpp::IntegerVector hashfun_2(IntegerVector vec);
-RcppExport SEXP LSHR_hashfun_2(SEXP vecSEXP) {
+RcppExport SEXP _LSHR_hashfun_2(SEXP vecSEXP) {
 BEGIN_RCPP
     Rcpp::RObject rcpp_result_gen;
     Rcpp::RNGScope rcpp_rngScope_gen;
@@ -29,7 +29,7 @@ END_RCPP
 }
 // get_minhash_matrix
 IntegerVector get_minhash_matrix(uint32_t unique_shingles_length, uint32_t hashfun_number, uint32_t seed);
-RcppExport SEXP LSHR_get_minhash_matrix(SEXP unique_shingles_lengthSEXP, SEXP hashfun_numberSEXP, SEXP seedSEXP) {
+RcppExport SEXP _LSHR_get_minhash_matrix(SEXP unique_shingles_lengthSEXP, SEXP hashfun_numberSEXP, SEXP seedSEXP) {
 BEGIN_RCPP
     Rcpp::RObject rcpp_result_gen;
     Rcpp::RNGScope rcpp_rngScope_gen;
@@ -42,7 +42,7 @@ END_RCPP
 }
 // sign_bit
 IntegerMatrix sign_bit(NumericMatrix x);
-RcppExport SEXP LSHR_sign_bit(SEXP xSEXP) {
+RcppExport SEXP _LSHR_sign_bit(SEXP xSEXP) {
 BEGIN_RCPP
     Rcpp::RObject rcpp_result_gen;
     Rcpp::RNGScope rcpp_rngScope_gen;
@@ -53,7 +53,7 @@ END_RCPP
 }
 // hash_signatures
 IntegerMatrix hash_signatures(IntegerMatrix m, int bands_number, int rows_per_band);
-RcppExport SEXP LSHR_hash_signatures(SEXP mSEXP, SEXP bands_numberSEXP, SEXP rows_per_bandSEXP) {
+RcppExport SEXP _LSHR_hash_signatures(SEXP mSEXP, SEXP bands_numberSEXP, SEXP rows_per_bandSEXP) {
 BEGIN_RCPP
     Rcpp::RObject rcpp_result_gen;
     Rcpp::RNGScope rcpp_rngScope_gen;
@@ -65,8 +65,8 @@ BEGIN_RCPP
 END_RCPP
 }
 // project_spmat
-IntegerVector project_spmat(const S4& m, int n, int hash_fun_id_offest, int n_threads);
-RcppExport SEXP LSHR_project_spmat(SEXP mSEXP, SEXP nSEXP, SEXP hash_fun_id_offestSEXP, SEXP n_threadsSEXP) {
+SEXP project_spmat(const S4& m, int n, int hash_fun_id_offest, int n_threads);
+RcppExport SEXP _LSHR_project_spmat(SEXP mSEXP, SEXP nSEXP, SEXP hash_fun_id_offestSEXP, SEXP n_threadsSEXP) {
 BEGIN_RCPP
     Rcpp::RObject rcpp_result_gen;
     Rcpp::RNGScope rcpp_rngScope_gen;
@@ -78,3 +78,18 @@ BEGIN_RCPP
     return rcpp_result_gen;
 END_RCPP
 }
+
+static const R_CallMethodDef CallEntries[] = {
+    {"_LSHR_hashfun_1", (DL_FUNC) &_LSHR_hashfun_1, 1},
+    {"_LSHR_hashfun_2", (DL_FUNC) &_LSHR_hashfun_2, 1},
+    {"_LSHR_get_minhash_matrix", (DL_FUNC) &_LSHR_get_minhash_matrix, 3},
+    {"_LSHR_sign_bit", (DL_FUNC) &_LSHR_sign_bit, 1},
+    {"_LSHR_hash_signatures", (DL_FUNC) &_LSHR_hash_signatures, 3},
+    {"_LSHR_project_spmat", (DL_FUNC) &_LSHR_project_spmat, 4},
+    {NULL, NULL, 0}
+};
+
+RcppExport void R_init_LSHR(DllInfo *dll) {
+    R_registerRoutines(dll, NULL, CallEntries, NULL, NULL);
+    R_useDynamicSymbols(dll, FALSE);
+}
diff --git a/src/random_projection.cpp b/src/random_projection.cpp
index 2f3ca6b..cdeb34f 100644
--- a/src/random_projection.cpp
+++ b/src/random_projection.cpp
@@ -29,7 +29,7 @@ int omp_thread_count() {
 }
 
 // [[Rcpp::export]]
-IntegerVector project_spmat(const S4 &m, int n, int hash_fun_id_offest, int n_threads = 0) {
+SEXP project_spmat(const S4 &m, int n, int hash_fun_id_offest, int n_threads = 0) {
   int num_threads = n_threads;
   if(num_threads == 0) num_threads = omp_thread_count();
   IntegerVector dims = m.slot("Dim");
@@ -42,8 +42,9 @@ IntegerVector project_spmat(const S4 &m, int n, int hash_fun_id_offest, int n_th
   NumericVector XX = m.slot("x");
   double *X = XX.begin();
 
-  IntegerVector res(N);
-  int *res_ptr = res.begin();
+  // IntegerVector res(N);
+  NumericVector res(N);
+  unsigned long long *res_ptr = (unsigned long long*)dataptr(res);
 
   #ifdef _OPENMP
   #pragma omp parallel for num_threads(num_threads)
@@ -52,7 +53,7 @@ IntegerVector project_spmat(const S4 &m, int n, int hash_fun_id_offest, int n_th
     uint32_t h1, h2;
     int p1 = P[i];
     int p2 = P[i + 1];
-    vector<float> row(32);
+    vector<float> row(64);
     float x;
     for(int k = p1; k < p2; k++) {
       int j = J[k];
@@ -67,15 +68,16 @@ IntegerVector project_spmat(const S4 &m, int n, int hash_fun_id_offest, int n_th
         row[hh] += ((int)h * x);
       }
     }
-    std::bitset<32> bitrow;
+    std::bitset<64> bitrow;
     for(int hh = 0; hh < n; hh++) {
       if(row[hh] < 0)
         bitrow[hh] = 0;
       else
         bitrow[hh] = 1;
     }
-    res_ptr[i] = bitrow.to_ulong();
+    res_ptr[i] = bitrow.to_ullong();
   }
+  res.attr("class") = "integer64";
   return res;
 }