diff --git a/README.md b/README.md
index 926f198..cf70937 100644
--- a/README.md
+++ b/README.md
@@ -13,26 +13,26 @@ authorization system and the key-document schema; the crypto primitives live in
 ## Install
 
 ```
-envelope_authorizer @ git+ssh://git@git.rethinkstudios.io/rethink-public/envelope_authorizer.git@v0.1.6
+envelope_authorizer @ git+ssh://git@git.rethinkstudios.io/rethink-public/envelope_authorizer.git@v0.1.7
 ```
 
 Direct:
 
 ```bash
-pip install "envelope_authorizer @ git+ssh://git@git.rethinkstudios.io/rethink-public/envelope_authorizer.git@v0.1.6"
+pip install "envelope_authorizer @ git+ssh://git@git.rethinkstudios.io/rethink-public/envelope_authorizer.git@v0.1.7"
 ```
 
 The base install uses a local JSON file for storage (stdlib only). For shared
 dev→server storage, install the mongo extra:
 
 ```bash
-pip install "envelope_authorizer[mongo] @ git+ssh://git@git.rethinkstudios.io/rethink-public/envelope_authorizer.git@v0.1.6"
+pip install "envelope_authorizer[mongo] @ git+ssh://git@git.rethinkstudios.io/rethink-public/envelope_authorizer.git@v0.1.7"
 ```
 
 Installing pulls `envelope_crypto` (and `mongo` with the extra). After install,
 the `authorizer` command is on your PATH; `python -m envelope_authorizer` also works.
 
-Drop the `@v0.1.6` suffix from the line above to install the latest unpinned.
+Drop the `@v0.1.7` suffix from the line above to install the latest unpinned.
 
 ## Trust model (read this)
 
diff --git a/pyproject.toml b/pyproject.toml
index 1d672de..bab698a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "envelope_authorizer"
-version = "0.1.6"
+version = "0.1.7"
 description = "CLI key-authorization manager for envelope_crypto"
 requires-python = ">=3.10"
 dependencies = [
diff --git a/src/envelope_authorizer/__init__.py b/src/envelope_authorizer/__init__.py
index 0a8da88..f1380ee 100644
--- a/src/envelope_authorizer/__init__.py
+++ b/src/envelope_authorizer/__init__.py
@@ -1 +1 @@
-__version__ = "0.1.6"
+__version__ = "0.1.7"
diff --git a/src/envelope_authorizer/commands/revoke.py b/src/envelope_authorizer/commands/revoke.py
index f064c5f..a7b28b0 100644
--- a/src/envelope_authorizer/commands/revoke.py
+++ b/src/envelope_authorizer/commands/revoke.py
@@ -23,7 +23,7 @@ def _find_by_fingerprint(storage, prefix: str):
     """
     if not prefix:
         raise CommandError("fingerprint prefix must not be empty")
-    matches = [doc for doc in storage.get_all() if doc.get("_id", "").startswith(prefix)]
+    matches = [doc for doc in storage.get_all() if (doc.get("_id") or "").startswith(prefix)]
     if len(matches) > 1:
         ids = ", ".join(d["_id"][:16] for d in matches)
         raise CommandError(f"fingerprint prefix '{prefix}' is ambiguous; matches: {ids}")