diff --git a/screenshots/Amanda_Gadrow.png b/screenshots/Amanda_Gadrow.png
new file mode 100644
index 0000000..377ab3a
Binary files /dev/null and b/screenshots/Amanda_Gadrow.png differ
diff --git a/week4/examples.R b/week4/examples.R
index 11e7009..d9d6770 100644
--- a/week4/examples.R
+++ b/week4/examples.R
@@ -1,3 +1,5 @@
+# Example 1
+
 f <- function(a) g(a)
 g <- function(b) h(b)
 h <- function(c) i(c)
@@ -12,8 +14,3 @@ traceback()
 
 options(error = recover)
 f("a")
-
-f <- function(n = 1e5) {
-  x <- rep(1, n)
-  rm(x)
-}
diff --git a/week4/index.qmd b/week4/index.qmd
index 10beded..9332468 100644
--- a/week4/index.qmd
+++ b/week4/index.qmd
@@ -26,6 +26,10 @@ schedule |>
 * renv
 * caching
 
+## Online resources
+
+* [Amanda Gadrow - Debugging in R](https://posit.co/resources/videos/debugging-techniques-in-rstudio-2/)
+
 ```{r}
 #| output: asis
 show_slides(week)
diff --git a/week4/slides.qmd b/week4/slides.qmd
index e7e6650..838eac3 100644
--- a/week4/slides.qmd
+++ b/week4/slides.qmd
@@ -13,7 +13,7 @@ format:
     fig-width: 7.5
     fig-height: 3.5
     include-in-header: ../header.tex
-    keep-tex: false
+    keep-tex: true
 ---
 
 ```{r}
@@ -35,6 +35,7 @@ source(here::here("course_info.R"))
 
 * Google
 * Stack Overflow
+* Posit Community
 * Create a minimal reproducible example
 * Create a unit test
 * Figure out where the test fails
@@ -95,7 +96,11 @@ traceback()
   * Similar to `browser()` but no change to source code.
   * Can be set in RStudio by clicking to the left of on the line number, or pressing `Shift + F9`.
 
-* `options(error = recover)`
+* `options(error = browser)`
+
+## Example
+
+[![Amanda Gadrow -- Debugging in R](../screenshots/Amanda_Gadrow.png)](https://posit.co/resources/videos/debugging-techniques-in-rstudio-2/)
 
 ## Interactive debugging
 
@@ -139,15 +144,9 @@ traceback()
 * `sink()` : capture output to file.
 * `options(warn = 2)` : turn warnings into errors.
 * `rlang::with_abort()` : turn messages into errors.
-* If R crashes, it is probably a bug in compiled code.
+* If R or RStudio crashes, it is probably a bug in compiled code.
 * Post minimal reproducible example to Posit Community or Stack Overflow.
 
-## Exercise
-
-Find the problem in the following code
-
-????
-
 # Profiling
 
 ## Profiling functions