diff --git a/DESCRIPTION b/DESCRIPTION
index e72686aa..dc199dc3 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -37,9 +37,6 @@ Imports:
     shiny (>= 1.4.0),
     xts,
     zoo
-LinkingTo: 
-    RcppSimdJson,
-    xts
 Suggests: 
     keyring,
     knitr,
diff --git a/NAMESPACE b/NAMESPACE
index 1198b8d4..ac5f81ae 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -78,9 +78,7 @@ importFrom(ggplot2,scale_x_continuous)
 importFrom(ggplot2,scale_y_continuous)
 importFrom(ggplot2,theme)
 importFrom(ggplot2,theme_grey)
-importFrom(mirai,mirai)
 importFrom(nanonext,ncurl)
-importFrom(secretbase,sha256)
 importFrom(shiny,HTML)
 importFrom(shiny,checkboxInput)
 importFrom(shiny,column)
diff --git a/NEWS.md b/NEWS.md
index ba1db491..1f4582de 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,9 @@
 # ichimoku 1.5.4.9000 (development)
 
+#### Updates:
+
+* Internal performance enhancements.
+
 # ichimoku 1.5.4
 
 #### Updates:
diff --git a/R/archive.R b/R/archive.R
index 2c1b3646..8f70c7ea 100644
--- a/R/archive.R
+++ b/R/archive.R
@@ -154,7 +154,7 @@ writeArchive <- function(object, file) {
     }
   }
 
-  x_archive_secure_hash <- sha256(object)
+  x_archive_secure_hash <- secretbase::sha256(object)
   save(object, x_archive_secure_hash, file = file, compress = TRUE)
   message(sprintf("Archive written to '%s'\nSHA256: %s", file, x_archive_secure_hash))
   invisible(file)
@@ -184,7 +184,7 @@ readArchive <- function(file) {
     stop("archive file was not created by archive()", call. = FALSE)
 
   message("Archive read from '", file, "'")
-  sha256 <- sha256(object)
+  sha256 <- secretbase::sha256(object)
   if (identical(sha256, x_archive_secure_hash))
     message("Data verified by SHA256: ", sha256) else
       warning(sprintf("SHA256 of restored object:   %s\ndoes not match the original: %s", sha256, x_archive_secure_hash), call. = FALSE)
diff --git a/R/data.R b/R/data.R
index ed26d017..ee75a88a 100644
--- a/R/data.R
+++ b/R/data.R
@@ -38,27 +38,29 @@
 
 .__global__ <- ".data"
 
-.user_agent <- sprintf("r-ichimoku/%s", as.character(packageVersion("ichimoku")))
+.user_agent <- sprintf("r-ichimoku/%s", format(packageVersion("ichimoku")))
 
-.mlgrid_pairs <- {
-  cols <- c("chikou", "close", "high", "low", "tenkan", "kijun", "senkouA", "senkouB", "cloudT", "cloudB")
-  pairs <- list(character(37L), character(37L))
-  ctr <- 0L
-  for (i in 1:7) {
-    colm <- cols[(i + 1L):10]
-    for (j in seq_along(colm)) {
-      colsi <- cols[i]
-      colmj <- colm[j]
-      if (colsi == "close" && (colmj == "high" || colmj == "low") ||
-         colsi == "high" && colmj == "low") next
-      ctr <- ctr + 1L
-      pairs[[1]][ctr] <- colsi
-      pairs[[2]][ctr] <- colmj
-      if (colsi == "senkouA" && colmj == "senkouB") break
+.mlgrid_pairs <- local(
+  {
+    cols <- c("chikou", "close", "high", "low", "tenkan", "kijun", "senkouA", "senkouB", "cloudT", "cloudB")
+    pairs <- list(character(37L), character(37L))
+    ctr <- 0L
+    for (i in 1:7) {
+      colm <- cols[(i + 1L):10]
+      for (j in seq_along(colm)) {
+        colsi <- cols[i]
+        colmj <- colm[j]
+        if (colsi == "close" && (colmj == "high" || colmj == "low") ||
+            colsi == "high" && colmj == "low") next
+        ctr <- ctr + 1L
+        pairs[[1]][ctr] <- colsi
+        pairs[[2]][ctr] <- colmj
+        if (colsi == "senkouA" && colmj == "senkouB") break
+      }
     }
+    pairs
   }
-  pairs
-}
+)
 
 .ichimoku_themes <- list(
   classic = c("#ffc6cb", "#c3dede", "#e0a9e0", "#db4525", "#1aa1a6", "#a4d1eb",
diff --git a/R/ichimoku-package.R b/R/ichimoku-package.R
index d13704f6..67d80fac 100644
--- a/R/ichimoku-package.R
+++ b/R/ichimoku-package.R
@@ -82,9 +82,7 @@
 #'     PositionIdentity rel scale_color_manual scale_fill_manual
 #'     scale_x_continuous scale_y_continuous Stat StatIdentity theme theme_grey
 #'     %+replace%
-#' @importFrom mirai mirai
 #' @importFrom nanonext ncurl
-#' @importFrom secretbase sha256
 #' @importFrom RcppSimdJson is_valid_json
 #' @importFrom shiny checkboxInput column downloadButton downloadHandler HTML
 #'     fillPage fluidPage fluidRow hoverOpts invalidateLater isolate
diff --git a/R/oanda.R b/R/oanda.R
index 420958bf..0320feba 100644
--- a/R/oanda.R
+++ b/R/oanda.R
@@ -578,7 +578,7 @@ oanda_studio <- function(instrument = "USD_JPY",
   isTRUE(new.process) && {
     mc <- match.call()
     mc[["new.process"]] <- NULL
-    return(invisible(mirai(mc, oanda_studio = oanda_studio)))
+    return(invisible(mirai::mirai(mc, oanda_studio = oanda_studio)))
   }
   if (!missing(instrument)) instrument <- sub("-", "_", toupper(force(instrument)), fixed = TRUE)
   granularity <- match.arg(granularity, c("D", "W", "M",