diff --git a/DESCRIPTION b/DESCRIPTION
index 5532799..719d0a1 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: matos
 Type: Package
 Title: Interface with the Mid-Atlantic Acoustic Telemetry Observing System (MATOS)
-Version: 0.3.005
+Version: 0.4.00
 Authors@R: person("Michael", "O'Brien", email = "mike@obrien.page",
                   role = c("aut", "cre"),
                   comment = c(ORCID = "0000-0003-1420-6395"))
diff --git a/NAMESPACE b/NAMESPACE
index 424a6dd..c180606 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -15,6 +15,7 @@ export(matos_receiver_summary)
 export(matos_tag_summary)
 export(set_matos_credentials)
 export(upload_file)
+importFrom(memoise,memoise)
 importFrom(utils,URLencode)
 importFrom(utils,browseURL)
 importFrom(utils,download.file)
diff --git a/NEWS.md b/NEWS.md
index 1473938..4b49438 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,25 +1,23 @@
-# matos 0.3.005
+# matos 0.4.00
+
+  - API calls are cached via the [memoise package](https://memoise.r-lib.org/index.html), meaning that MATOS is not queryed unless **absolutely** necessary. Big speed up when listing your files/projects!
+
+# matos 0.3
   - Precompile vignettes to allow [r-universe](https://mhpob.r-universe.dev/matos) to build. (matos 0.3.005)
   - Fix broken link in [`set_matos_credentials`](https://matos.obrien.page/reference/set_matos_credentials.html) documentation. (matos 0.3.004)
   - Fix [`upload_file`](https://matos.obrien.page/reference/upload_file.html) to actually allow multiple uploads. (matos 0.3.003)
-
-# matos 0.3
-
   - The meat of what were `make_tag_push_summary` and `make_receiver_push_summary` have been moved over to a new package: [`otndo`](https://otndo.obrien.page). These functions now wrap those in `otndo` and have been renamed [`matos_tag_summary`](https://matos.obrien.page/reference/matos_tag_summary.html) and [`matos_receiver_summary`](https://matos.obrien.page/reference/matos_receiver_summary.html), respectively.
   - [`list_extract_files`](https://matos.obrien.page/reference/list_extract_files.html) and [`list_project_files`](https://matos.obrien.page/reference/list_project_files.html) now accept vectors of different detection/file types to subset the returned data frame.
   - Misc. tests have been added
 
-# matos 0.2.13
-
-  - [`matos_logoff`](https://matos.obrien.page/reference/matos_logoff.html), allowing you to log out of your MATOS session.
-  - A draft vignette on how to manage multiple telemetry projects by using `matos` in parallel.
-  - [`make_receiver_push_summary`](https://matos.obrien.page/reference/make_receiver_push_summary.html) and [`make_tag_push_summary`](https://matos.obrien.page/reference/make_tag_push_summary.html) now scrape the OTN GeoServer in order to get a correct title for your project summaries!
-  - A more-informative error now appears if you try to find information on a project that doesn't exist.
-
 # matos 0.2.1
 
-  - The website has moved to [https://matos.obrien.page/](https://matos.obrien.page/).
-  - [`set_matos_credentials`](https://matos.obrien.page/reference/set_matos_credentials.html) 
+  - [`matos_logoff`](https://matos.obrien.page/reference/matos_logoff.html), allowing you to log out of your MATOS session. (matos 0.2.13)
+  - A draft vignette on how to manage multiple telemetry projects by using `matos` in parallel. (matos 0.2.13)
+  - [`make_receiver_push_summary`](https://matos.obrien.page/reference/make_receiver_push_summary.html) and [`make_tag_push_summary`](https://matos.obrien.page/reference/make_tag_push_summary.html) now scrape the OTN GeoServer in order to get a correct title for your project summaries! (matos 0.2.13)
+  - A more-informative error now appears if you try to find information on a project that doesn't exist. (matos 0.2.13)
+  - The website has moved to [https://matos.obrien.page/](https://matos.obrien.page/). (matos 0.2.1)
+  - [`set_matos_credentials`](https://matos.obrien.page/reference/set_matos_credentials.html)
     - *NEW* function!
     - Allows you to store your MATOS credentials in your [.Renviron](https://rstats.wtf/r-startup.html#renviron) for seamless log in.
   - [`make_tag_push_summary`](https://matos.obrien.page/reference/make_tag_push_summary.html)
diff --git a/R/matos-package.R b/R/matos-package.R
index 885cae7..b470e53 100644
--- a/R/matos-package.R
+++ b/R/matos-package.R
@@ -10,6 +10,7 @@
 #' @importFrom utils download.file
 #' @importFrom utils txtProgressBar
 #' @importFrom utils setTxtProgressBar
+#' @importFrom memoise memoise
 #' @keywords internal
 "_PACKAGE"
 
diff --git a/R/zzz.R b/R/zzz.R
new file mode 100644
index 0000000..8c9bb29
--- /dev/null
+++ b/R/zzz.R
@@ -0,0 +1,5 @@
+.onLoad <- function(libname, pkgname) {
+  list_my_projects <<- memoise::memoise(list_my_projects)
+  list_projects <<- memoise::memoise(list_projects)
+  get_file_list <<- memoise::memoise(get_file_list)
+}