diff --git a/context-restore/SKILL.md b/context-restore/SKILL.md
index eede99b7..f059ca32 100644
--- a/context-restore/SKILL.md
+++ b/context-restore/SKILL.md
@@ -755,7 +755,7 @@ Parse the user's input:
 
 ```bash
 eval "$(~/.claude/skills/gstack/bin/gstack-slug 2>/dev/null)" && mkdir -p ~/.gstack/projects/$SLUG
-CHECKPOINT_DIR="$HOME/.gstack/projects/$SLUG/checkpoints"
+CHECKPOINT_DIR="${GSTACK_HOME:-$HOME/.gstack}/projects/$SLUG/checkpoints"
 if [ ! -d "$CHECKPOINT_DIR" ]; then
   echo "NO_CHECKPOINTS"
 else
diff --git a/context-restore/SKILL.md.tmpl b/context-restore/SKILL.md.tmpl
index d9303289..1fe9f938 100644
--- a/context-restore/SKILL.md.tmpl
+++ b/context-restore/SKILL.md.tmpl
@@ -62,7 +62,7 @@ Parse the user's input:
 
 ```bash
 {{SLUG_SETUP}}
-CHECKPOINT_DIR="$HOME/.gstack/projects/$SLUG/checkpoints"
+CHECKPOINT_DIR="${GSTACK_HOME:-$HOME/.gstack}/projects/$SLUG/checkpoints"
 if [ ! -d "$CHECKPOINT_DIR" ]; then
   echo "NO_CHECKPOINTS"
 else
diff --git a/context-save/SKILL.md b/context-save/SKILL.md
index a3a60581..e190cb72 100644
--- a/context-save/SKILL.md
+++ b/context-save/SKILL.md
@@ -811,7 +811,7 @@ allowlist: only `a-z 0-9 - .` survive.
 
 ```bash
 eval "$(~/.claude/skills/gstack/bin/gstack-slug 2>/dev/null)" && mkdir -p ~/.gstack/projects/$SLUG
-CHECKPOINT_DIR="$HOME/.gstack/projects/$SLUG/checkpoints"
+CHECKPOINT_DIR="${GSTACK_HOME:-$HOME/.gstack}/projects/$SLUG/checkpoints"
 mkdir -p "$CHECKPOINT_DIR"
 TIMESTAMP=$(date +%Y%m%d-%H%M%S)
 # Bash-side title sanitize. Pass the raw title as $1 when running this block.
@@ -897,7 +897,7 @@ Restore later with /context-restore.
 
 ```bash
 eval "$(~/.claude/skills/gstack/bin/gstack-slug 2>/dev/null)" && mkdir -p ~/.gstack/projects/$SLUG
-CHECKPOINT_DIR="$HOME/.gstack/projects/$SLUG/checkpoints"
+CHECKPOINT_DIR="${GSTACK_HOME:-$HOME/.gstack}/projects/$SLUG/checkpoints"
 if [ -d "$CHECKPOINT_DIR" ]; then
   echo "CHECKPOINT_DIR=$CHECKPOINT_DIR"
   # Use find + sort instead of ls -1t: filename YYYYMMDD-HHMMSS prefix is the
diff --git a/context-save/SKILL.md.tmpl b/context-save/SKILL.md.tmpl
index 81dbf4f8..8343873f 100644
--- a/context-save/SKILL.md.tmpl
+++ b/context-save/SKILL.md.tmpl
@@ -118,7 +118,7 @@ allowlist: only `a-z 0-9 - .` survive.
 
 ```bash
 {{SLUG_SETUP}}
-CHECKPOINT_DIR="$HOME/.gstack/projects/$SLUG/checkpoints"
+CHECKPOINT_DIR="${GSTACK_HOME:-$HOME/.gstack}/projects/$SLUG/checkpoints"
 mkdir -p "$CHECKPOINT_DIR"
 TIMESTAMP=$(date +%Y%m%d-%H%M%S)
 # Bash-side title sanitize. Pass the raw title as $1 when running this block.
@@ -204,7 +204,7 @@ Restore later with /context-restore.
 
 ```bash
 {{SLUG_SETUP}}
-CHECKPOINT_DIR="$HOME/.gstack/projects/$SLUG/checkpoints"
+CHECKPOINT_DIR="${GSTACK_HOME:-$HOME/.gstack}/projects/$SLUG/checkpoints"
 if [ -d "$CHECKPOINT_DIR" ]; then
   echo "CHECKPOINT_DIR=$CHECKPOINT_DIR"
   # Use find + sort instead of ls -1t: filename YYYYMMDD-HHMMSS prefix is the