diff --git a/.Rbuildignore b/.Rbuildignore
index b47dc56..c8d7320 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -5,5 +5,6 @@
 ^docs$
 ^pkgdown$
 ^\.github$
+^build-vignettes\.md$
 ^cran-comments\.md$
 ^CRAN-SUBMISSION$
diff --git a/build-vignettes.md b/build-vignettes.md
new file mode 100644
index 0000000..5b43a73
--- /dev/null
+++ b/build-vignettes.md
@@ -0,0 +1,12 @@
+Due to the time-consuming computations involved in the vignettes of the *cisp* package, 
+it is necessary to pre-build the vignettes prior to package submission.
+
+``` r
+.prebuild_vignettes = \(name){
+  out = paste0("vignettes/",name,".Rmd")
+  inp = paste0(out,".orig")
+  knitr::knit(inp,out)
+}
+
+.prebuild_vignettes("cisp")
+```
diff --git a/vignettes/cisp.rmd b/vignettes/cisp.rmd
index 4bbb0c5..b3d4bbf 100644
--- a/vignettes/cisp.rmd
+++ b/vignettes/cisp.rmd
@@ -65,7 +65,7 @@ system.time({
   g = cisp::spc(ndvi,cores = 6)
 })
 ##    user  system elapsed 
-##    0.84    0.20   21.50
+##    0.66    0.26   24.88
 g
 ## ***   Spatial Pattern Correlation    
 ## 
diff --git a/vignettes/precompile.r b/vignettes/precompile.r
deleted file mode 100644
index 2f3bb7a..0000000
--- a/vignettes/precompile.r
+++ /dev/null
@@ -1,4 +0,0 @@
-devtools::load_all()
-
-knitr::knit("vignettes/cisp.rmd.orig",
-            "vignettes/cisp.rmd")