diff --git a/DESCRIPTION b/DESCRIPTION
index 406f50a..633c0c6 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: fisdata
 Title: Query Data from the FIS Web Page
-Version: 0.2.0.9001
+Version: 0.2.0.9002
 Authors@R: 
   person("Stefan", "Lanz", , "slanz1137@gmail.com", role = c("aut", "cre"))
 Description: Query data from the web site of the International Ski and
@@ -28,17 +28,18 @@ Imports:
     rlang,
     cli,
     magrittr,
-    clipr,
     cachem,
+    jsonlite
+Suggests:
     ggplot2,
-    grid,
     scales,
     colorspace,
     ggnewscale,
     ggiraph,
+    grid,
     png,
-    jpeg
-Suggests: 
+    jpeg,
+    clipr,
     roxygen2,
     spelling,
     withr,
diff --git a/NAMESPACE b/NAMESPACE
index f661033..3af1eb9 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -1,5 +1,6 @@
 # Generated by roxygen2: do not edit by hand
 
+export("%>%")
 export(browse_url)
 export(fd_def)
 export(get_athlete_image)
@@ -17,10 +18,13 @@ export(query_events)
 export(query_race)
 export(query_results)
 export(query_standings)
+export(read_fisdata_defaults)
 export(reset_fisdata_defaults)
 export(set_fisdata_defaults)
 export(show_url)
 export(summarise_results)
+export(write_current_fisdata_defaults)
+export(write_fisdata_defaults)
 importFrom(dplyr,"%>%")
 importFrom(rlang,":=")
 importFrom(rlang,.data)
diff --git a/R/defaults.R b/R/defaults.R
index 0406912..ec3e6ad 100644
--- a/R/defaults.R
+++ b/R/defaults.R
@@ -38,58 +38,20 @@ set_fisdata_defaults <- function(sector = NULL,
     }
   }
 
-  if (!is.null(sector)) {
-    use_sector <- find_code(sector, "sector")
-    options(fisdata_sector = use_sector)
-    alert_default("sector", use_sector, verbose)
-  }
-
-  if (!is.null(season)) {
-    season_int <- suppressWarnings(as.integer(season))
-    if (season == "") {
-      options(fisdata_season = "")
-      alert_default("season", season, verbose)
-    } else if (is.na(season_int) | season_int < 1950 |
-        season_int > lubridate::year(today()) + 1) {
-      cli::cli_warn("'{season}' is not a valid season.")
-    } else {
-      options(fisdata_season = as.character(season_int))
-      alert_default("season", season_int, verbose)
-    }
-  }
-
-  if (!is.null(gender)) {
-    use_gender <- standardise_gender(gender)
-    if (!use_gender %in% c("", "M", "W")) {
-      cli::cli_warn("'{gender}' is not a valid gender code.")
-    } else {
-      options(fisdata_gender = use_gender)
-      alert_default("gender", use_gender, verbose)
-    }
-  }
-
-  if (!is.null(category)) {
-    use_category <- find_code(category, "category")
-    options(fisdata_category = use_category)
-      alert_default("category", use_category, verbose)
-  }
-
-  if (!is.null(discipline)) {
-    # when matching the discipline, use the default value for the sector
-    # if set_fisdata_defaults has been called with a sector, it's value has
-    # already been set as the default such that it will also be used here
-    use_discipline <- find_code(discipline, "discipline",
-                                sector = fd_def("sector"))
-    options(fisdata_discipline = use_discipline)
-    alert_default("discipline", use_discipline, verbose)
-  }
-
-  if (!is.null(active_only)) {
-    if (!active_only %in% c(TRUE, FALSE)) {
-      cli::cli_warn("'{active_only}' is not valid for active_only.")
-    } else {
-      options(fisdata_active_only = active_only)
-      alert_default("active_only", active_only, verbose)
+  defs <- prepare_defaults(sector = sector,
+                           season = season,
+                           gender = gender,
+                           category = category,
+                           discipline = discipline,
+                           active_only = active_only)
+  
+  for (name in names(defs)) {
+    value <- defs[[name]]
+    if (!is.null(value)) {
+      options(
+        magrittr::set_names(list(value), paste0("fisdata_", name))
+      )
+      alert_default(name, verbose)
     }
   }
 }
@@ -127,13 +89,165 @@ fd_def <- function(name = c("sector", "season", "gender",
 }
 
 
+#' Read and Write Defaults from a JSON File
+#'
+#' Default settings can be written to a JSON file and read again from
+#' this file. If the file `.fisdata.json` exists in the user's home
+#' it is read automatically when fisdata is loaded in an interactive
+#' session (see 'Details' for how to configure this behaviour).
+#' 
+#' @param file name of the JSON file to read or write
+#' @param overwrite should an existing file be overwritten?
+#' @inheritParams query_athletes
+#' @inheritParams query_results
+#' 
+#' @details
+#' When fisdata is loaded in an interactive session, it tries to load defaults
+#' from a file `fisdata.json`. You can use another file by setting the environment
+#' variable `FISDATA_DEFAULTS_FILE` to the path to this file before loading
+#' fisdata. To do this once, you can use [Sys.setenv()], to configure R to always
+#' load a different file, you can set `FISDATA_DEFAULTS_FILE` in your `.Renviron`
+#' file. 
+#' 
+#' @returns
+#' `write_fisdata_defaults()` and `write_current_fisdata_defaults()` return the json-string that
+#' was written to the file (invisibly). `read_fisdata_defaults()` returns the default
+#' values that were read as a tibble (invisibly).
+#' 
+#' @export
+
+write_fisdata_defaults <- function(file = "~/.fisdata.json",
+                                   overwrite = FALSE,
+                                   sector = "",
+                                   season = "",
+                                   gender = "",
+                                   category = "",
+                                   discipline = "",
+                                   active_only = FALSE) {
+  defs <- prepare_defaults(sector = sector,
+                           season = season,
+                           gender = gender,
+                           category = category,
+                           discipline = discipline,
+                           active_only = active_only)
+  write_fisdata_defaults_(defs, file, overwrite)
+}
+
+
+#' @rdname write_fisdata_defaults
+#' @export
+
+write_current_fisdata_defaults <- function(file = "~/.fisdata.json",
+                                           overwrite = FALSE) {
+  write_fisdata_defaults_(get_fisdata_defaults(), file, overwrite)
+}
+
+
+# helper function that writes a list or tibble of defaults to a JSON file
+write_fisdata_defaults_ <- function(defaults, 
+                                    file = "~/.fisdata.json",
+                                    overwrite = FALSE,
+                                    error_call = rlang::caller_env()) {
+  
+  if (file.exists(file) && !overwrite) {
+    cli::cli_abort("The file {file} exists. Use `overwrite = TRUE` to overwrite it.")
+  }
+
+  # don't write NULL for any default to the file
+  def_is_null <- purrr::map_lgl(defaults, is.null)
+  if (any(def_is_null)) {
+    null_names <- names(def_is_null)[def_is_null]
+    cli::cli_abort(
+      c(
+        "!" = "Defaults must no be NULL when writing to a json file.", 
+        "i" = "The following value{?s} {?is/are} NULL: {null_names}."
+      ),
+      call = error_call
+    )
+  }
+
+  json <- defaults %>%
+    # convert to a list to avoid having an unnecessary length-one array
+    as.list() %>% 
+    jsonlite::toJSON(pretty = TRUE, auto_unbox = TRUE)
+
+  writeLines(json, file)
+
+  invisible(json)
+}
+
+
+#' @param apply should the defaults be applied? 
+#' @param verbose should the function create output. This defaults
+#'  to `TRUE` in interactive sessions or when `apply` is `FALSE`.
+#' @rdname write_fisdata_defaults
+#' 
+#' @export
+
+read_fisdata_defaults <- function(file = "~/.fisdata.json", 
+                          apply = TRUE,
+                          verbose = !apply || interactive()) {
+
+  if (!file.exists(file)) {
+    cli::cli_abort("The file {file} does not exist.")
+  }
+
+  raw <- purrr::possibly(jsonlite::fromJSON)(file)
+  if (is.null(raw)) {
+    cli::cli_abort("Failed to parse file {file} as JSON.")
+  }
+
+  # check that all the expected values are present.
+  expected <- c("sector", "season", "gender", "category", "discipline", "active_only")
+  is_present <- expected %in% names(raw)
+  if (any(!is_present)) {
+    cli::cli_abort("Some defaults have no value set: {expected[!is_present]}")
+  }
+
+  # run the contents of the file through prepare_defs() to check
+  # that the values are valid.
+  error_call = rlang::current_call()
+  defs <- tryCatch(
+    do.call(prepare_defaults, raw[names(raw) %in% expected]),
+    error = function(e) {
+      cli::cli_abort(c("The contents of file {file} are not valid.",
+                       "i" = "Error message: {e$message}"),
+                      call = error_call)
+    },
+    warning = function(w) {
+      cli::cli_abort(c("The contents of file {file} are not valid.",
+                       "i" = "Warning message: {w$message}"),
+                      call = error_call)
+    }
+  )
+
+  # if verbose and the default are not to be applied, print them here
+  # in case the defaults are applied, set_fisdata_defaults() will create output.
+  if (verbose && !apply) {
+    cli::cli_alert_info("The file {file} contains the following defaults:")
+    print(dplyr::as_tibble(defs))
+  }
+
+  # if requested, apply the defaults
+  if (apply) {
+    do.call(set_fisdata_defaults, c(defs, list(verbose = verbose)))
+  }
+
+  invisible(dplyr::as_tibble(defs))
+}
+
+
 # issue a message describing the default value that has been set.
-alert_default <- function(type, value, verbose) {
+# The function must be called AFTER setting the default.
+alert_default <- function(type, verbose) {
 
   if (!verbose) {
     return(NULL)
   }
 
+  # get the default value that has been set
+  value <- fd_def(type)
+  
   # if the value is an empty string, issue a message saying this
   if (value == "") {
     cli::cli_alert_info("The default for '{type}' has been set to ''.")
@@ -151,3 +265,66 @@ alert_default <- function(type, value, verbose) {
     }
   }
 }
+
+
+# prepare inputs for default values
+prepare_defaults <- function(sector = NULL,
+                             season = NULL,
+                             gender = NULL,
+                             category = NULL,
+                             discipline = NULL,
+                             active_only = NULL) {
+  
+  if (!is.null(sector)) {
+    sector <- find_code(sector, "sector")
+  }
+
+  if (!is.null(season)) {
+    season_int <- suppressWarnings(as.integer(season))
+    if (season == "") {
+      season <- ""
+    } else if (is.na(season_int) | season_int < 1950 |
+        season_int > lubridate::year(today()) + 1) {
+      cli::cli_warn("'{season}' is not a valid season.")
+      season <- NULL
+    } else {
+      season <- as.character(season_int)
+    }
+  }
+
+  if (!is.null(gender)) {
+    std_gender <- standardise_gender(gender)
+    if (!std_gender %in% c("", "M", "W")) {
+      cli::cli_warn("'{gender}' is not a valid gender code.")
+      gender <- NULL
+    } else {
+      gender <- std_gender
+    }
+  }
+
+  if (!is.null(category)) {
+    category <- find_code(category, "category")
+  }
+
+  if (!is.null(discipline)) {
+    # discipline depends on sector. If a sector has been passed to this
+    # function, use it. Otherwise, use the current default.
+    discipline_sector <- if (!is.null(sector)) sector else fd_def("sector")
+    discipline <- find_code(discipline, "discipline",
+                            sector = discipline_sector)
+  }
+
+  if (!is.null(active_only)) {
+    if (!active_only %in% c(TRUE, FALSE)) {
+      cli::cli_warn("'{active_only}' is not valid for active_only.")
+      active_only <- NULL
+    }
+  }
+  
+  list(sector = sector,
+       season = season,
+       gender = gender,
+       category = category,
+       discipline = discipline,
+       active_only = active_only)
+}
\ No newline at end of file
diff --git a/R/fisdata-package.R b/R/fisdata-package.R
index 6641390..791a23a 100644
--- a/R/fisdata-package.R
+++ b/R/fisdata-package.R
@@ -27,6 +27,23 @@ cache <- new.env()
 
   # set options to default values
   reset_fisdata_defaults()
+
+  # determine the file that defaults should be read from. The file name is
+  # taken from the environment variable FISDATA_DEFAULTS_FILE. If the variable
+  # is unset, fall back to "~/.fisdata.json".
+  defaults_file <- Sys.getenv("FISDATA_DEFAULTS_FILE", "~/.fisdata.json")
+
+  # if the file exists and R is running interactively,
+  # read defaults from it.
+  if (interactive() && file.exists(defaults_file)) {
+    cli::cli_alert_info("Reading default values from {defaults_file} ...")
+    read_fisdata_defaults(defaults_file, verbose = TRUE)
+  }
 }
 
 # nocov end
+
+
+# reexport %>% for convenience
+#' @export
+dplyr::`%>%`
\ No newline at end of file
diff --git a/R/helpers.R b/R/helpers.R
index b771f1e..1bf5ea8 100644
--- a/R/helpers.R
+++ b/R/helpers.R
@@ -24,7 +24,14 @@
 show_url <- function(fisdata_df) {
   url <- attr(fisdata_df, "url")
   if (interactive() && !is.null(url)) {
-    clipr::write_clip(url) # nocov
+    if (rlang::is_installed("clipr")) { # nocov start
+      clipr::write_clip(url)
+    } else {
+      cli::cli_alert_info(
+        c("Install {.pkg clipr} with {.run install.packages(\"clipr\")} ",
+          "to automatically copy the url to the clipboard.")
+      )
+    } # nocov end
   }
   url
 }
diff --git a/R/img_audio.R b/R/img_audio.R
index 351efa6..b967a4a 100644
--- a/R/img_audio.R
+++ b/R/img_audio.R
@@ -25,6 +25,8 @@
 #' @export
 
 get_athlete_image <- function(athlete, file = NULL) {
+  rlang::check_installed(c("grid", "png", "jpeg"), "to process images")
+
   athlete <- ensure_one_athlete(athlete)
   id <- athlete$competitor_id
 
diff --git a/R/plot.R b/R/plot.R
index 15e2f32..5cd4f7f 100644
--- a/R/plot.R
+++ b/R/plot.R
@@ -32,6 +32,10 @@ plot_rank_summary <- function(results,
                               interactive = TRUE,
                               width = NULL,
                               height = NULL) {
+  rlang::check_installed(
+    c("ggplot2", "colorspace", "ggnewscale", "ggiraph"),
+    "to create plots."
+  )
 
   by <- match_groupings(by, c("category", "discipline"))
 
@@ -101,6 +105,10 @@ plot_results_summary <- function(results,
                                  interactive = TRUE,
                                  width = NULL,
                                  height = NULL) {
+  rlang::check_installed(
+    c("ggplot2", "scales", "ggiraph"),
+    "to create plots."
+  )
 
   variable <- match.arg(variable)
 
@@ -218,7 +226,11 @@ plot_ranks_over_time <- function(results,
                                  interactive = TRUE,
                                  width = NULL,
                                  height = NULL) {
-
+  rlang::check_installed(
+    c("ggplot2", "colorspace", "ggnewscale", "ggiraph"),
+    "to create plots."
+  )
+  
   by <- if (length(by) > 0 && all(!is.na(by))) match.arg(by)
   time <- match.arg(time)
   type <- match.arg(type)
@@ -328,6 +340,10 @@ plot_results_over_time <- function(results,
                                    interactive = TRUE,
                                    width = NULL,
                                    height = NULL) {
+  rlang::check_installed(
+    c("ggplot2", "scales", "ggiraph"),
+    "to create plots."
+  )
 
   variable <- match.arg(variable)
   by <- if (length(by) > 0 && all(!is.na(by))) match.arg(by)
diff --git a/inst/WORDLIST b/inst/WORDLIST
index 601035d..dea917c 100644
--- a/inst/WORDLIST
+++ b/inst/WORDLIST
@@ -14,6 +14,7 @@ Wengen
 dnf
 ggiraph
 ggplot
+json
 parasports
 png
 pos
diff --git a/man/reexports.Rd b/man/reexports.Rd
new file mode 100644
index 0000000..3238477
--- /dev/null
+++ b/man/reexports.Rd
@@ -0,0 +1,16 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/fisdata-package.R
+\docType{import}
+\name{reexports}
+\alias{reexports}
+\alias{\%>\%}
+\title{Objects exported from other packages}
+\keyword{internal}
+\description{
+These objects are imported from other packages. Follow the links
+below to see their documentation.
+
+\describe{
+  \item{dplyr}{\code{\link[dplyr:reexports]{\%>\%}}}
+}}
+
diff --git a/man/write_fisdata_defaults.Rd b/man/write_fisdata_defaults.Rd
new file mode 100644
index 0000000..029a006
--- /dev/null
+++ b/man/write_fisdata_defaults.Rd
@@ -0,0 +1,82 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/defaults.R
+\name{write_fisdata_defaults}
+\alias{write_fisdata_defaults}
+\alias{write_current_fisdata_defaults}
+\alias{read_fisdata_defaults}
+\title{Read and Write Defaults from a JSON File}
+\usage{
+write_fisdata_defaults(
+  file = "~/.fisdata.json",
+  overwrite = FALSE,
+  sector = "",
+  season = "",
+  gender = "",
+  category = "",
+  discipline = "",
+  active_only = FALSE
+)
+
+write_current_fisdata_defaults(file = "~/.fisdata.json", overwrite = FALSE)
+
+read_fisdata_defaults(
+  file = "~/.fisdata.json",
+  apply = TRUE,
+  verbose = !apply || interactive()
+)
+}
+\arguments{
+\item{file}{name of the JSON file to read or write}
+
+\item{overwrite}{should an existing file be overwritten?}
+
+\item{sector}{abbreviation of the sector, e.g., "AL" for
+alpine skiing. Not case-sensitive.
+See the dataset \link{sectors} for possible values.
+If a string not matching a sector code is used, a similar string
+is searched for in the description column of \link{sectors}.}
+
+\item{season}{year when the season ended, i.e., 2020 stands for the season
+2019/2020. It is not possible to filter for multiple seasons at once.}
+
+\item{gender}{abbreviation of the gender: "M" for male/men,
+"F" or "W" for female/women.}
+
+\item{category}{abbreviation of the category of the race, e.g., "WC" for
+"World Cup". Not case-sensitive.
+See the dataset \link{categories} for possible values.
+If a string not matching a category code is used, a similar string
+is searched for in the description column of \link{categories}.}
+
+\item{discipline}{abbreviation for the discipline, e.g., "DH" for
+"Downhill". Not case sensitive.
+See the dataset \link{disciplines} for possible values.
+If a string not matching a discipline code is used, a similar string
+is searched for in the description column of \link{disciplines}.}
+
+\item{active_only}{should the query be restricted to active athletes.}
+
+\item{apply}{should the defaults be applied?}
+
+\item{verbose}{should the function create output. This defaults
+to \code{TRUE} in interactive sessions or when \code{apply} is \code{FALSE}.}
+}
+\value{
+\code{write_fisdata_defaults()} and \code{write_current_fisdata_defaults()} return the json-string that
+was written to the file (invisibly). \code{read_fisdata_defaults()} returns the default
+values that were read as a tibble (invisibly).
+}
+\description{
+Default settings can be written to a JSON file and read again from
+this file. If the file \code{.fisdata.json} exists in the user's home
+it is read automatically when fisdata is loaded in an interactive
+session (see 'Details' for how to configure this behaviour).
+}
+\details{
+When fisdata is loaded in an interactive session, it tries to load defaults
+from a file \code{fisdata.json}. You can use another file by setting the environment
+variable \code{FISDATA_DEFAULTS_FILE} to the path to this file before loading
+fisdata. To do this once, you can use \code{\link[=Sys.setenv]{Sys.setenv()}}, to configure R to always
+load a different file, you can set \code{FISDATA_DEFAULTS_FILE} in your \code{.Renviron}
+file.
+}
diff --git a/pkgdown/_pkgdown.yml b/pkgdown/_pkgdown.yml
index 18c8023..6d06b7f 100644
--- a/pkgdown/_pkgdown.yml
+++ b/pkgdown/_pkgdown.yml
@@ -32,6 +32,7 @@ reference:
   - show_url
   - browse_url
   - set_fisdata_defaults
+  - write_fisdata_defaults
 
 - title: Datasets
   desc: Datasets describing values that can be used in the querying functions
diff --git a/tests/testthat/test-defaults.R b/tests/testthat/test-defaults.R
index bce9688..0dbfd48 100644
--- a/tests/testthat/test-defaults.R
+++ b/tests/testthat/test-defaults.R
@@ -2,6 +2,8 @@ library(stringr)
 library(lubridate, warn.conflicts = FALSE)
 library(tibble)
 library(glue)
+library(withr)
+library(jsonlite)
 
 fd_opts <- paste0(
   "fisdata_",
@@ -51,7 +53,7 @@ test_that("set_fisdata_defaults() works with valid inputs", {
 })
 
 
-test_that("set_fisdata_defaults() works with \"\"", {
+test_that('set_fisdata_defaults() works with ""', {
   set_fisdata_defaults(sector = "")
   expect_equal(getOption("fisdata_sector"), "")
 
@@ -196,6 +198,162 @@ test_that("fd_def() works", {
 })
 
 
-# reset all defaults to their initial state
-reset_fisdata_defaults()
+test_that("write_current_fisdata_defaults() works", {
+  reset_fisdata_defaults()
+  set_fisdata_defaults(sector = "AL", gender = "F", category = "WC")
+  ref <- toJSON(
+    list(sector = "AL", season = "", gender = "W", category = "WC",
+         discipline = "", active_only = FALSE),
+    auto_unbox = TRUE,
+    pretty = TRUE
+  )
+  local_file("fisdata.json")
+  expect_equal(write_current_fisdata_defaults("fisdata.json"), ref)
+  expect_true(file.exists("fisdata.json"))
+  expect_equal(paste(readLines("fisdata.json"), collapse = "\n"), ref,
+               ignore_attr = TRUE)
+})
+
+
+test_that("write_current_fisdata_defaults() handles existing file", {
+  local_file("fisdata.json")
+  write_current_fisdata_defaults("fisdata.json")
+  expect_error(write_current_fisdata_defaults("fisdata.json"),
+               "The file fisdata.json exists.")
+  expect_silent(write_current_fisdata_defaults("fisdata.json", overwrite = TRUE))
+})
+
+
+test_that("write_fisdata_defaults() works", {
+  ref <- toJSON(
+    list(sector = "CC", season = "", gender = "M", category = "WC",
+         discipline = "", active_only = FALSE),
+    auto_unbox = TRUE,
+    pretty = TRUE
+  )
+  local_file("fisdata.json")
+  expect_equal(
+    write_fisdata_defaults("fisdata.json", sector = "CC", gender = "M", category = "WC"),
+    ref
+  )
+  expect_true(file.exists("fisdata.json"))
+  expect_equal(paste(readLines("fisdata.json"), collapse = "\n"), ref,
+               ignore_attr = TRUE)
+})
+
+
+test_that("write_fisdata_defaults() handles existing file", {
+  local_file("fisdata.json")
+  write_fisdata_defaults("fisdata.json", sector = "CC", gender = "M")
+  expect_error(write_fisdata_defaults("fisdata.json", sector = "CC", gender = "M"),
+               "The file fisdata.json exists.")
+  expect_silent(write_current_fisdata_defaults("fisdata.json", overwrite = TRUE))
+})
+
+
+test_that("write_fisdata_defaults() rejects NULL as default", {
+  local_file("fisdata.json")
+  expect_error(write_fisdata_defaults("fisdata.json", sector = "CC", discipline = NULL),
+               "Defaults must no be NULL.*NULL: discipline")
+  expect_false(file.exists("fisdata.json"))
+})
+
+
+test_that("read_fisdata_defaults() reads defaults without applying them", {
+  local_file("fisdata.json")
+  write_fisdata_defaults("fisdata.json", sector = "AL", season = "2024", gender = "W", 
+                 category = "WC", discipline = "SL", active_only = TRUE)
+  reset_fisdata_defaults()
+
+  expect_equal(
+    read_fisdata_defaults("fisdata.json", apply = FALSE, verbose = FALSE),
+    tibble(sector = "AL", season = "2024", gender = "W", category = "WC",
+           discipline = "SL", active_only = TRUE)
+  )
+  expect_equal(
+    get_fisdata_defaults(),
+    tibble(sector = "", season = "", gender = "",
+           category = "", discipline = "", active_only = FALSE)
+  )
+})
+
+
+test_that("read_fisdata_defaults() applies defaults", {
+  local_file("fisdata.json")
+  write_fisdata_defaults("fisdata.json", sector = "CC", season = "2025", gender = "M", 
+                 category = "WC", discipline = "SP", active_only = TRUE)
+  reset_fisdata_defaults()
+
+  expect_equal(
+    read_fisdata_defaults("fisdata.json", verbose = FALSE),
+    tibble(sector = "CC", season = "2025", gender = "M",
+           category = "WC", discipline = "SP", active_only = TRUE)
+  )
+  expect_equal(
+    get_fisdata_defaults(),
+    tibble(sector = "CC", season = "2025", gender = "M",
+           category = "WC", discipline = "SP", active_only = TRUE)
+  )
+})
 
+
+test_that("read_fisdata_defaults() handles invalid files", {
+  local_file("fisdata.json")
+
+  expect_error(read_fisdata_defaults("fisdata.json"), "does not exist")
+
+  writeLines("{", "fisdata.json")
+  expect_error(read_fisdata_defaults("fisdata.json"), "Failed to parse")
+
+  writeLines(
+    toJSON(
+      list(sector = "AL", season = "2024", gender = "W", category = "WC",
+           discipline = "SL"),
+      auto_unbox = TRUE
+    ),
+    "fisdata.json"
+  )
+  expect_error(read_fisdata_defaults("fisdata.json"), "Some defaults have no value set: active_only")
+
+  writeLines(
+    toJSON(
+      list(sector = c("AL", "CC"), season = "1940", gender = "W", category = "WC",
+           discipline = "SL", active_only = TRUE),
+      auto_unbox = TRUE
+    ),
+    "fisdata.json"
+  )
+  expect_error(read_fisdata_defaults("fisdata.json"), "contents.*not valid")
+
+  writeLines(
+    toJSON(
+      list(sector = "AL", season = "1940", gender = "W", category = "WC",
+           discipline = "SL", active_only = TRUE),
+      auto_unbox = TRUE
+    ),
+    "fisdata.json"
+  )
+  expect_error(read_fisdata_defaults("fisdata.json"), "'1940' is not a valid season")
+})
+
+
+test_that("read_fisdata_defaults() creates output in the appropriate situations", {
+  local_file("fisdata.json")
+  write_fisdata_defaults("fisdata.json", sector = "CC", season = "2025", gender = "M", 
+                 category = "WC", discipline = "SP", active_only = TRUE)
+  
+  expect_silent(read_fisdata_defaults("fisdata.json", apply = FALSE, verbose = FALSE))
+  expect_silent(read_fisdata_defaults("fisdata.json", apply = TRUE, verbose = FALSE))
+  read_fisdata_defaults("fisdata.json", apply = FALSE, verbose = TRUE) %>% 
+    expect_message("contains the following defaults") %>% 
+    expect_output("tibble.*sector +season +gender +category")
+  read_fisdata_defaults("fisdata.json", apply = TRUE, verbose = TRUE) %>%
+    expect_message("sector.*CC.*Cross-Country") %>%
+    expect_message("season.*2025") %>%
+    expect_message("gender.*M") %>%
+    expect_message("category.*WC.*World Cup") %>%
+    expect_message("discipline.*SP") %>%
+    expect_message("active_only.*'TRUE'")
+})
+
+reset_fisdata_defaults()