diff --git a/pm/store.py b/pm/store.py
index 5305490c07..7dba809be4 100644
--- a/pm/store.py
+++ b/pm/store.py
@@ -222,8 +222,8 @@ def tree_digest(root: Path) -> str:
     """Deterministic sha256 over a directory tree: walk every file, sort
     by posix relpath, hash `relpath\\0<content>` per entry. No mtimes, no
     mode bits. Symlinks contribute their LINK TARGET TEXT (os.readlink),
-    not the target's bytes — the link is the data. Directory symlinks are
-    not followed.
+    not the target's bytes — the link is the data. Directory symlinks and
+    junctions are not followed.
 
     ``__pycache__`` directories are skipped: CPython writes .pyc caches
     into them the first time the staged interpreter runs (uv venv/uv sync
@@ -233,7 +233,14 @@ def tree_digest(root: Path) -> str:
 
     files: list[tuple[str, Path]] = []
     for dirpath, dirnames, filenames in os.walk(root):
-        dirnames[:] = [d for d in sorted(dirnames) if d != "__pycache__"]
+        descend = []
+        for name in sorted(dirnames):
+            path = Path(dirpath) / name
+            if path.is_symlink() or path.is_junction():
+                files.append((path.relative_to(root).as_posix(), path))
+            elif name != "__pycache__":
+                descend.append(name)
+        dirnames[:] = descend
         for fname in filenames:
             path = Path(dirpath) / fname
             files.append((path.relative_to(root).as_posix(), path))
@@ -243,7 +250,7 @@ def tree_digest(root: Path) -> str:
     for rel, path in files:
         digest.update(rel.encode("utf-8"))
         digest.update(b"\0")
-        if path.is_symlink():
+        if path.is_symlink() or path.is_junction():
             digest.update(os.readlink(path).encode("utf-8"))
         else:
             with open(path, "rb") as f:
diff --git a/tests/pm/test_tree_digest_links.py b/tests/pm/test_tree_digest_links.py
new file mode 100644
index 0000000000..44d1cbb0f2
--- /dev/null
+++ b/tests/pm/test_tree_digest_links.py
@@ -0,0 +1,73 @@
+"""Realized digests bind link text without reading the linked directory."""
+import os
+from pathlib import Path
+
+import pytest
+
+from pm.store import tree_digest
+
+
+@pytest.mark.platforms("windows", "posix")
+def test_directory_links_bind_only_their_target_text(tmp_path):
+    root = tmp_path / "tree"
+    root.mkdir()
+    (root / "payload").write_bytes(b"unchanged")
+    left, right = tmp_path / "left", tmp_path / "right"
+    for target in (left, right):
+        target.mkdir()
+        (target / "content").write_bytes(b"same bytes")
+    plain = tree_digest(root)
+    link = root / "directory"
+    try:
+        link.symlink_to(Path("..") / "left", target_is_directory=True)
+    except OSError as exc:
+        if getattr(exc, "winerror", None) == 1314:
+            pytest.skip("directory symlinks require Windows Developer Mode or privilege")
+        raise
+    first = tree_digest(root)
+    assert first != plain
+    (left / "content").write_bytes(b"changed outside the tree")
+    assert tree_digest(root) == first
+    link.unlink()
+    link.symlink_to(Path("..") / "right", target_is_directory=True)
+    assert tree_digest(root) != first
+    link.unlink()
+    link.symlink_to(".", target_is_directory=True)
+    cycle = tree_digest(root)
+    assert tree_digest(root) == cycle
+    assert cycle not in (plain, first)
+
+
+@pytest.mark.platforms("windows")
+def test_junctions_bind_target_text_without_walking_outside(tmp_path):
+    import subprocess
+
+    root = tmp_path / "tree"
+    root.mkdir()
+    left, right = tmp_path / "left", tmp_path / "right"
+    for target in (left, right):
+        target.mkdir()
+        (target / "content").write_bytes(b"same bytes")
+    junction = root / "junction"
+    command = str(Path(os.environ["SystemRoot"]) / "System32" / "cmd.exe")
+
+    def point_at(target):
+        result = subprocess.run(
+            [command, "/d", "/c", "mklink", "/J", str(junction), str(target)],
+            capture_output=True, text=True, encoding="utf-8", errors="replace", timeout=15,
+        )
+        assert result.returncode == 0, result.stdout + result.stderr
+        assert junction.is_junction()
+
+    point_at(left)
+    try:
+        first = tree_digest(root)
+        (left / "content").write_bytes(b"changed outside the tree")
+        assert tree_digest(root) == first
+        junction.rmdir()
+        point_at(right)
+        assert tree_digest(root) != first
+    finally:
+        junction.rmdir()
+    assert (left / "content").read_bytes() == b"changed outside the tree"
+    assert (right / "content").read_bytes() == b"same bytes"