diff --git a/.Rbuildignore b/.Rbuildignore
index 54336f4..44aa68b 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -16,3 +16,5 @@ Rprof\.out
 ^scripts$
 ^vignettes_src$
 ^appveyor\.yml$
+^.*\.Rproj$
+^\.Rproj\.user$
diff --git a/DESCRIPTION b/DESCRIPTION
index 4d7b8ef..b1d482a 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -15,6 +15,7 @@ URL: https://github.com/richfitz/storr
 BugReports: https://github.com/richfitz/storr/issues
 Imports:
     R6 (>= 2.1.0),
+    base64url,
     digest
 Suggests:
     DBI (>= 0.6),
@@ -27,5 +28,5 @@ Suggests:
     rbenchmark,
     testthat (>= 1.0.0)
 VignetteBuilder: knitr
-RoxygenNote: 6.0.1
+RoxygenNote: 6.1.0
 Encoding: UTF-8
diff --git a/NAMESPACE b/NAMESPACE
index 88661fb..525212e 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -19,3 +19,4 @@ export(storr_rds)
 export(storr_redis_api)
 export(test_driver)
 importFrom(R6,R6Class)
+importFrom(base64url,base64_urlencode)
diff --git a/R/base64.R b/R/base64.R
index ad10230..3dd5296 100644
--- a/R/base64.R
+++ b/R/base64.R
@@ -9,6 +9,7 @@
 ##' @param pad Logical, indicating if strings should be padded with
 ##'   \code{=} characters (as RFC 4648 requires)
 ##' @export
+##' @importFrom base64url base64_urlencode
 ##' @examples
 ##' x <- encode64("hello")
 ##' x
@@ -21,28 +22,22 @@ encode64 <- function(x, char62 = "-", char63 = "_", pad = TRUE) {
   if (length(x) != 1L) {
     return(vcapply(x, encode64, char62, char63, pad, USE.NAMES = FALSE))
   }
-  tr <- c(LETTERS, letters, 0:9, char62, char63)
-  x <- as.integer(charToRaw(x))
-  n_bytes <- length(x)
-  n_blocks <- ceiling(n_bytes / 3L)
-  n_pad <- 3L * n_blocks - n_bytes
-
-  ## The integer() call here pads the *input* to have the correct number
-  ## of blocks of bytes.
-  x <- matrix(c(x, integer(3L * n_blocks - n_bytes)), 3L, n_blocks)
-
-  y <- matrix(integer(4 * n_blocks), 4L, n_blocks)
-  y[1L, ] <- bitwShiftR(x[1L, ], 2L)
-  y[2L, ] <- bitwOr(bitwShiftL(x[1L, ], 4L), bitwShiftR(x[2L, ], 4L))
-  y[3L, ] <- bitwOr(bitwShiftL(x[2L, ], 2L), bitwShiftR(x[3L, ], 6L))
-  y[4L, ] <- x[3L, ]
-
-  z <- tr[bitwAnd(y, 63L) + 1L]
-  if (n_pad > 0) {
-    len <- length(z)
-    z[(len - n_pad + 1):len] <- if (pad) "=" else ""
+  out <- base64url::base64_urlencode(x)
+  if (!identical(char62, "-")) {
+    gsub(pattern = "-", replacement = char62, x = out, fixed = TRUE)
+  }
+  if (!identical(char63, "_")) {
+    gsub(pattern = "_", replacement = char62, x = out, fixed = TRUE)
+  }
+  if (pad) {
+    x <- as.integer(charToRaw(x))
+    n_bytes <- length(x)
+    n_blocks <- ceiling(n_bytes / 3L)
+    n_pad <- 3L * n_blocks - n_bytes
+    char_pad <- replicate(n_pad, "=")
+    out <- paste(c(out, char_pad), collapse = "")
   }
-  paste0(z, collapse = "")
+  out
 }
 
 
diff --git a/man/storr_rds.Rd b/man/storr_rds.Rd
index 4e46782..a5c4e23 100644
--- a/man/storr_rds.Rd
+++ b/man/storr_rds.Rd
@@ -5,8 +5,9 @@
 \alias{driver_rds}
 \title{rds object cache driver}
 \usage{
-storr_rds(path, compress = NULL, mangle_key = NULL, mangle_key_pad = NULL,
-  hash_algorithm = NULL, default_namespace = "objects")
+storr_rds(path, compress = NULL, mangle_key = NULL,
+  mangle_key_pad = NULL, hash_algorithm = NULL,
+  default_namespace = "objects")
 
 driver_rds(path, compress = NULL, mangle_key = NULL,
   mangle_key_pad = NULL, hash_algorithm = NULL)