diff --git a/include/raft.h b/include/raft.h
index d63710d11..3d7960d87 100644
--- a/include/raft.h
+++ b/include/raft.h
@@ -502,20 +502,6 @@ struct raft_io
 };
 
 /*
- * version 1:
- * struct raft_fsm
- * {
- *     int version;
- *     void *data;
- *     int (*apply)(struct raft_fsm *fsm,
- *                  const struct raft_buffer *buf,
- *                  void **result);
- *     int (*snapshot)(struct raft_fsm *fsm,
- *                     struct raft_buffer *bufs[],
- *                     unsigned *n_bufs);
- *     int (*restore)(struct raft_fsm *fsm, struct raft_buffer *buf);
- * };
- *
  * version 2:
  * introduces `snapshot_finalize`, when this method is not NULL, it will
  * always run after a successful call to `snapshot`, whether the snapshot has
@@ -537,6 +523,7 @@ struct raft_fsm
                     struct raft_buffer *bufs[],
                     unsigned *n_bufs);
     int (*restore)(struct raft_fsm *fsm, struct raft_buffer *buf);
+    /* Fields below added since version 2. */
     int (*snapshot_finalize)(struct raft_fsm *fsm,
                              struct raft_buffer *bufs[],
                              unsigned *n_bufs);
diff --git a/include/raft/fixture.h b/include/raft/fixture.h
index d4a76f511..e28251830 100644
--- a/include/raft/fixture.h
+++ b/include/raft/fixture.h
@@ -74,15 +74,24 @@ struct raft_fixture
 };
 
 /**
+ * !!! DEPRECATED users should use `raft_fixture_initialize`. !!!
+ *
  * Initialize a raft cluster fixture with @n servers. Each server will use an
  * in-memory @raft_io implementation and one of the given @fsms. All servers
  * will be initially connected to one another, but they won't be bootstrapped or
  * started.
  */
+__attribute__((deprecated("use raft_fixture_initialize")))
 RAFT_API int raft_fixture_init(struct raft_fixture *f,
                                unsigned n,
                                struct raft_fsm *fsms);
 
+/**
+ * Initialize a raft cluster fixture. Servers can be added by using
+ * `raft_fixture_grow`.
+ */
+RAFT_API int raft_fixture_initialize(struct raft_fixture *f);
+
 /**
  * Release all memory used by the fixture.
  */
diff --git a/src/fixture.c b/src/fixture.c
index 926d08dd8..f324b8541 100644
--- a/src/fixture.c
+++ b/src/fixture.c
@@ -978,6 +978,15 @@ int raft_fixture_init(struct raft_fixture *f, unsigned n, struct raft_fsm *fsms)
     return 0;
 }
 
+int raft_fixture_initialize(struct raft_fixture *f)
+{
+    f->time = 0;
+    logInit(&f->log);
+    f->commit_index = 0;
+    f->hook = NULL;
+    return 0;
+}
+
 void raft_fixture_close(struct raft_fixture *f)
 {
     unsigned i;
diff --git a/test/integration/test_fixture.c b/test/integration/test_fixture.c
index 443229a68..a2cd0efac 100644
--- a/test/integration/test_fixture.c
+++ b/test/integration/test_fixture.c
@@ -29,9 +29,14 @@ static void *setUp(const MunitParameter params[], MUNIT_UNUSED void *user_data)
         FsmInit(&f->fsms[i], 2);
     }
 
-    rc = raft_fixture_init(&f->fixture, N_SERVERS, f->fsms);
+    rc = raft_fixture_initialize(&f->fixture);
     munit_assert_int(rc, ==, 0);
 
+    for (i = 0; i < N_SERVERS; i++) {
+        rc = raft_fixture_grow(&f->fixture, &f->fsms[i]);
+        munit_assert_int(rc, ==, 0);
+    }
+
     rc = raft_fixture_configuration(&f->fixture, N_SERVERS, &configuration);
     munit_assert_int(rc, ==, 0);
 
diff --git a/test/lib/cluster.h b/test/lib/cluster.h
index f908b7522..28b74ff9b 100644
--- a/test/lib/cluster.h
+++ b/test/lib/cluster.h
@@ -44,11 +44,13 @@
                 atoi(munit_parameters_get(params, CLUSTER_FSM_VERSION_PARAM)); \
         }                                                                      \
         munit_assert_int(_n, >, 0);                                            \
+        _rv = raft_fixture_initialize(&f->cluster);                            \
+        munit_assert_int(_rv, ==, 0);                                          \
         for (_i = 0; _i < _n; _i++) {                                          \
             FsmInit(&f->fsms[_i], _fsm_version);                               \
+            _rv = raft_fixture_grow(&f->cluster, &f->fsms[_i]);                \
+            munit_assert_int(_rv, ==, 0);                                      \
         }                                                                      \
-        _rv = raft_fixture_init(&f->cluster, _n, f->fsms);                     \
-        munit_assert_int(_rv, ==, 0);                                          \
         for (_i = 0; _i < _n; _i++) {                                          \
             raft_set_pre_vote(raft_fixture_get(&f->cluster, _i), _pre_vote);   \
             if (_hb) {                                                         \