diff --git a/lib/DB.zig b/lib/DB.zig
index f6f7edc..2b112ff 100644
--- a/lib/DB.zig
+++ b/lib/DB.zig
@@ -9,6 +9,7 @@ const Allocator = std.mem.Allocator;
 const ArrayList = std.ArrayList;
 const AutoHashMap = std.AutoHashMap;
 const BoundedArray = std.BoundedArray;
+const ArenaAllocator = std.heap.ArenaAllocator;
 
 const Corpus = @import("Corpus.zig");
 const pad = @import("padding.zig");
@@ -257,6 +258,7 @@ fn groupMemberNames(
     arr.len = num_members;
 
     var buf = std.ArrayList(u8).init(allocator);
+    errdefer buf.deinit();
     // +num_members are for sentinel zeroes
     try buf.ensureTotalCapacity(total_members_len + num_members);
 
@@ -624,7 +626,9 @@ test "high-level API" {
     var db = try DB.fromCorpus(allocator, &corpus);
     defer db.deinit(allocator);
 
-    const all = try db.getgrnam(allocator, "all");
+    var arena = ArenaAllocator.init(allocator);
+    defer arena.deinit();
+    const all = try db.getgrnam(arena.allocator(), "all");
     try testing.expect(all != null);
     try testing.expectEqual(all.?.gid, 9999);
     try testing.expectEqualStrings(all.?.name, "all");