diff --git a/pure.zsh b/pure.zsh
index beb71eb..e7cf07d 100644
--- a/pure.zsh
+++ b/pure.zsh
@@ -197,6 +197,14 @@ prompt_pure_preprompt_render() {
 		psvar[21]="${node_symbol}${prompt_pure_node_version}"
 	fi
 
+	# psvar[22]: Custom prefix, psvar[23]: Custom suffix.
+	# Set by the user-defined prompt_pure_precustom function.
+	psvar[22]=
+	psvar[23]=
+	if (( $+functions[prompt_pure_precustom] )); then
+		prompt_pure_precustom
+	fi
+
 	# Expand the prompt for future comparison.
 	local expanded_prompt
 	expanded_prompt="${(S%%)PROMPT}"
@@ -941,7 +949,7 @@ prompt_pure_preview() {
 	fi
 
 	# Sample preprompt with all components visible.
-	print -P "%F{$c[suspended_jobs]}${PURE_SUSPENDED_JOBS_SYMBOL-✦}%f %F{$c[user]}zaphod%f${host_sample} ${path_sample} %F{$c[git:branch]}main%f%F{$c[git:dirty]}*+%f %F{$c[git:action]}rebase-i%f %F{$c[git:arrow]}${PURE_GIT_DOWN_ARROW:-⇣}${PURE_GIT_UP_ARROW:-⇡}%f %F{$c[git:stash]}${PURE_GIT_STASH_SYMBOL-≡}%f %F{$c[node_version]}${node_symbol}22%f %F{$c[execution_time]}42s%f"
+	print -P "%F{$c[custom:prefix]}prefix%f %F{$c[suspended_jobs]}${PURE_SUSPENDED_JOBS_SYMBOL-✦}%f %F{$c[user]}zaphod%f${host_sample} ${path_sample} %F{$c[git:branch]}main%f%F{$c[git:dirty]}*+%f %F{$c[git:action]}rebase-i%f %F{$c[git:arrow]}${PURE_GIT_DOWN_ARROW:-⇣}${PURE_GIT_UP_ARROW:-⇡}%f %F{$c[git:stash]}${PURE_GIT_STASH_SYMBOL-≡}%f %F{$c[node_version]}${node_symbol}22%f %F{$c[execution_time]}42s%f %F{$c[custom:suffix]}suffix%f"
 	print -P "%F{$c[virtualenv]}venv%f %F{$c[prompt:success]}${PURE_PROMPT_SYMBOL:-❯}%f"
 	print
 	print -P "%F{$c[prompt:error]}${PURE_PROMPT_SYMBOL:-❯}%f  prompt after error"
@@ -984,6 +992,8 @@ prompt_pure_setup() {
 	# Set the colors.
 	typeset -gA prompt_pure_colors_default prompt_pure_colors
 	prompt_pure_colors_default=(
+		custom:prefix        242
+		custom:suffix        242
 		execution_time       yellow
 		git:arrow            cyan
 		git:stash            cyan
@@ -1038,13 +1048,16 @@ prompt_pure_setup() {
 	#   psvar[19] = exec time (e.g. 1d 3h 2m 5s)
 	#   psvar[20] = virtualenv/conda/nix-shell name
 	#   psvar[21] = Node.js version (e.g. ⬢22)
+	#   psvar[22] = custom prefix (set by prompt_pure_precustom)
+	#   psvar[23] = custom suffix (set by prompt_pure_precustom)
 	#
 	# Example output:
-	#   ✦ user@host ~/Code/pure main*+ rebase ⇣⇡ ≡ ⬢22 3s
+	#   prefix ✦ user@host ~/Code/pure main*+ rebase ⇣⇡ ≡ ⬢22 3s suffix
 	#   myenv ❯
 	#
 	# Preprompt line: each %(NV..) section only renders when its psvar is non-empty.
-	PROMPT='%(12V.%F{$prompt_pure_colors[suspended_jobs]}%12v%f .)'
+	PROMPT='%(22V.%F{$prompt_pure_colors[custom:prefix]}%22v%f .)'
+	PROMPT+='%(12V.%F{$prompt_pure_colors[suspended_jobs]}%12v%f .)'
 	local hostname_part=''
 	if (( prompt_pure_state[show_host] )); then
 		hostname_part='%F{$prompt_pure_colors[host]}@%m%f'
@@ -1058,6 +1071,7 @@ prompt_pure_setup() {
 	PROMPT+='%(18V. %F{$prompt_pure_colors[git:stash]}%18v%f.)'
 	PROMPT+='%(21V. %F{$prompt_pure_colors[node_version]}%21v%f.)'
 	PROMPT+='%(19V. %F{$prompt_pure_colors[execution_time]}%19v%f.)'
+	PROMPT+='%(23V. %F{$prompt_pure_colors[custom:suffix]}%23v%f.)'
 
 	# Newline separating preprompt from prompt.
 	PROMPT+='${prompt_newline}'
diff --git a/readme.md b/readme.md
index fbac6cb..2dce6ce 100644
--- a/readme.md
+++ b/readme.md
@@ -133,6 +133,38 @@ Automatic terminal title management can be disabled if you want to set your own
 
 `zstyle :prompt:pure:title show no`
 
+## Customization
+
+Pure supports a hook function for adding custom content to the prompt. Define a function called `prompt_pure_precustom` in your `.zshrc` (after `prompt pure`) to set custom prefix and suffix segments on the preprompt line:
+
+- `psvar[22]` — Custom prefix, rendered before all built-in segments.
+- `psvar[23]` — Custom suffix, rendered after all built-in segments.
+
+The function is called each time the prompt renders (including async redraws), so avoid slow commands. For expensive operations, cache the result in a `precmd` hook and read the cached value in `prompt_pure_precustom`.
+
+```sh
+# .zshrc
+
+# Cache expensive calls in precmd (runs once per command, not on async redraws).
+my_kube_context=
+my_precmd() {
+	my_kube_context=$(kubectl config current-context 2>/dev/null)
+}
+add-zsh-hook precmd my_precmd
+
+prompt_pure_precustom() {
+	psvar[22]=$my_kube_context
+	psvar[23]=$(date +%H:%M)
+}
+```
+
+The colors can be customized with `zstyle`:
+
+```sh
+zstyle :prompt:pure:custom:prefix color cyan
+zstyle :prompt:pure:custom:suffix color yellow
+```
+
 ## Colors
 
 As explained in ZSH's [manual](http://zsh.sourceforge.net/Doc/Release/Zsh-Line-Editor.html#Character-Highlighting), color values can be:
@@ -141,6 +173,8 @@ As explained in ZSH's [manual](http://zsh.sourceforge.net/Doc/Release/Zsh-Line-E
 - `#` followed by an RGB triplet in hexadecimal format, for example `#424242`. Only if your terminal supports 24-bit colors (true color) or when the [`zsh/nearcolor` module](http://zsh.sourceforge.net/Doc/Release/Zsh-Modules.html#The-zsh_002fnearcolor-Module) is loaded.
 
 Colors can be changed by using [`zstyle`](http://zsh.sourceforge.net/Doc/Release/Zsh-Modules.html#The-zsh_002fzutil-Module) with a pattern of the form `:prompt:pure:$color_name` and style `color`. The color names, their default, and what part they affect are:
+- `custom:prefix` (242) - Custom prefix set via `prompt_pure_precustom`.
+- `custom:suffix` (242) - Custom suffix set via `prompt_pure_precustom`.
 - `execution_time` (yellow) - The execution time of the last command when exceeding `PURE_CMD_MAX_EXEC_TIME`.
 - `git:arrow` (cyan) - For `PURE_GIT_UP_ARROW` and `PURE_GIT_DOWN_ARROW`.
 - `git:stash` (cyan) - For `PURE_GIT_STASH_SYMBOL`.
@@ -162,22 +196,25 @@ Colors can be changed by using [`zstyle`](http://zsh.sourceforge.net/Doc/Release
 The following diagram shows where each color is applied on the prompt:
 
 ```
-┌────────────────────────────────────────────────────── user
-│      ┌─────────────────────────────────────────────── host
-│      │           ┌─────────────────────────────────── path
-│      │           │          ┌──────────────────────── git:branch
-│      │           │          │   ┌─────────────────────── git:dirty
-│      │           │          │   │  ┌──────────────────── git:action
-│      │           │          │   │  │        ┌─────────── git:arrow
-│      │           │          │   │  │        │ ┌───────── git:stash
-│      │           │          │   │  │        │ │ ┌─────── node_version
-│      │           │          │   │  │        │ │ │   ┌── execution_time
-│      │           │          │   │  │        │ │ │   │
-zaphod@heartofgold ~/dev/pure main*+ rebase-i ⇡ ≡ ⬢22 42s
+┌──────────────────────────────────────────────────────────────────────── custom:prefix
+│      ┌─────────────────────────────────────────────────────────────────── suspended_jobs
+│      │ ┌───────────────────────────────────────────────────────────────── user
+│      │ │      ┌────────────────────────────────────────────────────────── host
+│      │ │      │           ┌────────────────────────────────────────────── path
+│      │ │      │           │          ┌─────────────────────────────────── git:branch
+│      │ │      │           │          │   ┌─────────────────────────────── git:dirty
+│      │ │      │           │          │   │  ┌──────────────────────────── git:action
+│      │ │      │           │          │   │  │        ┌─────────────────── git:arrow
+│      │ │      │           │          │   │  │        │ ┌───────────────── git:stash
+│      │ │      │           │          │   │  │        │ │ ┌─────────────── node_version
+│      │ │      │           │          │   │  │        │ │ │   ┌─────────── execution_time
+│      │ │      │           │          │   │  │        │ │ │   │   ┌────── custom:suffix
+│      │ │      │           │          │   │  │        │ │ │   │   │
+prefix ✦ zaphod@heartofgold ~/dev/pure main*+ rebase-i ⇡ ≡ ⬢22 42s suffix
 venv ❯
 │    │
-│    └──────────────────────────────────────────────── prompt
-└───────────────────────────────────────────────────── virtualenv (or prompt:continuation)
+│    └───────────────────────────────────────────────────────────────────── prompt
+└────────────────────────────────────────────────────────────────────────── virtualenv (or prompt:continuation)
 ```
 
 ### Preview
diff --git a/tests/preview.zsh b/tests/preview.zsh
index c0717c9..e3a127d 100644
--- a/tests/preview.zsh
+++ b/tests/preview.zsh
@@ -5,6 +5,8 @@ source "${0:A:h}/test-helper.zsh"
 main() {
 	# Set up colors like prompt_pure_setup would.
 	typeset -gA prompt_pure_colors=(
+		custom:prefix        242
+		custom:suffix        242
 		execution_time       yellow
 		git:arrow            cyan
 		git:stash            cyan
@@ -29,7 +31,7 @@ main() {
 	local output
 	output=$(prompt_pure_preview 2>&1)
 
-	for component in zaphod heartofgold "~/dev/pure" "main" "rebase-i" "42s" "venv" "prompt after error" "continuation prompt" "root" "branch color when data is cached"; do
+	for component in prefix suffix zaphod heartofgold "~/dev/pure" "main" "rebase-i" "42s" "venv" "prompt after error" "continuation prompt" "root" "branch color when data is cached"; do
 		if [[ $output != *"$component"* ]]; then
 			print -u2 "Missing component in preview output: $component"
 			return 1