diff --git a/DESCRIPTION b/DESCRIPTION
index 454d531..d771815 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -5,8 +5,12 @@ Version: 0.1.0
 Author: Who wrote it
 Maintainer: Who to complain to <yourfault@somewhere.net>
 Description: More about what it does (maybe more than one line)
-License: What license is it under?
-LazyData: MIT
+License: GPL-3
+LazyData: true
 Imports:
-    htmltools
+    htmltools,
+    htmlwidgets,
+    shiny
+Suggests:
+    rmarkdown
 RoxygenNote: 5.0.1
diff --git a/R/controls.R b/R/controls.R
index 38c1c6f..4d1fac0 100644
--- a/R/controls.R
+++ b/R/controls.R
@@ -30,7 +30,7 @@ jqueryLib <- function() {
 }
 
 #' @export
-filter_select <- function(id, label, sharedData, group, allLevels = FALSE,
+filter_select <- function(id, label, sharedData, group = "default", allLevels = FALSE,
   multiple = TRUE) {
 
   df <- sharedData$data(
@@ -39,9 +39,8 @@ filter_select <- function(id, label, sharedData, group, allLevels = FALSE,
     withKey = TRUE
   )
 
-  df <- df %>%
-    dplyr::group_by_(group = group) %>%
-    dplyr::summarise(key = list(key_))
+  # TODO: should this package really depend on dplyr?
+  df <- dplyr::summarise(dplyr::group_by(df, g = group), key = list(key_))
 
   if (is.factor(df$g) && allLevels) {
     labels <- as.character(levels(df$g))
@@ -57,6 +56,7 @@ filter_select <- function(id, label, sharedData, group, allLevels = FALSE,
     group = sharedData$groupName()
   )
 
+  # TODO: should this be spitting out an HTMLwidget?
   attachDependencies(
     tags$div(class = "form-group",
       tags$label(class = "control-label", `for` = id, label),
diff --git a/R/crosstalk.R b/R/crosstalk.R
index 7deaa57..362def7 100644
--- a/R/crosstalk.R
+++ b/R/crosstalk.R
@@ -114,6 +114,9 @@ SharedData <- R6Class(
   ),
   public = list(
     initialize = function(data, key, interactionMode = "select", group = "default") {
+      if (!missing(key) && length(key) == 1 && !key %in% names(data)) {
+        warning("key argument not found in names of data", call. = FALSE)
+      }
       private$.data <- data
       private$.key <- key
       private$.filterCV <- ClientValue$new("filter", group)
@@ -158,6 +161,7 @@ SharedData <- R6Class(
       df[[private$.key]]
     },
     data = function(withSelection = FALSE, withFilter = TRUE, withKey = FALSE) {
+
       df <- if (shiny::is.reactive(private$.data)) {
         private$.data()
       } else {