diff --git a/include/cglm/call/mat4.h b/include/cglm/call/mat4.h
index 35b9f66..c9ad796 100644
--- a/include/cglm/call/mat4.h
+++ b/include/cglm/call/mat4.h
@@ -53,10 +53,6 @@ CGLM_EXPORT
 void
 glmc_mat4_mulv(mat4 m, vec4 v, vec4 dest);
 
-CGLM_EXPORT
-void
-glmc_mat4_mulq(mat4 m, versor q, mat4 dest);
-
 CGLM_EXPORT
 void
 glmc_mat4_quat(mat4 m, versor dest);
diff --git a/include/cglm/mat4.h b/include/cglm/mat4.h
index fd7a340..27ebe05 100644
--- a/include/cglm/mat4.h
+++ b/include/cglm/mat4.h
@@ -319,21 +319,6 @@ glm_mat4_mulv(mat4 m, vec4 v, vec4 dest) {
 #endif
 }
 
-/*!
- * @brief multiply mat4 with quaternion and store in dest vector
- *
- * @param[in]  m    left matrix
- * @param[in]  q    quaternion as right matrix
- * @param[out] dest destination matrix
- */
-CGLM_INLINE
-void
-glm_mat4_mulq(mat4 m, versor q, mat4 dest) {
-  mat4 rot;
-  glm_quat_mat4(q, rot);
-  glm_mat4_mul(m, rot, dest);
-}
-
 /*!
  * @brief convert mat4's rotation part to quaternion
  *
diff --git a/include/cglm/quat.h b/include/cglm/quat.h
index 664a069..95a768e 100644
--- a/include/cglm/quat.h
+++ b/include/cglm/quat.h
@@ -15,8 +15,10 @@
    CGLM_INLINE void glm_quat_init(versor q, float x, float y, float z, float w);
    CGLM_INLINE void glm_quat(versor q, float angle, float x, float y, float z);
    CGLM_INLINE void glm_quatv(versor q, float angle, vec3 axis);
+   CGLM_INLINE void glm_quat_copy(versor q, versor dest);
    CGLM_INLINE float glm_quat_norm(versor q);
    CGLM_INLINE void glm_quat_normalize(versor q);
+   CGLM_INLINE void glm_quat_normalize_to(versor q, versor dest);
    CGLM_INLINE float glm_quat_dot(versor q1, versor q2);
    CGLM_INLINE void glm_quat_conjugate(versor q, versor dest);
    CGLM_INLINE void glm_quat_inv(versor q, versor dest);
@@ -30,8 +32,20 @@
    CGLM_INLINE void glm_quat_axis(versor q, versor dest);
    CGLM_INLINE void glm_quat_mul(versor p, versor q, versor dest);
    CGLM_INLINE void glm_quat_mat4(versor q, mat4 dest);
-   CGLM_INLINE void glm_quat_mat3(versor q, mat3 dest)
+   CGLM_INLINE void glm_quat_mat4t(versor q, mat4 dest);
+   CGLM_INLINE void glm_quat_mat3(versor q, mat3 dest);
+   CGLM_INLINE void glm_quat_mat3t(versor q, mat3 dest);
+   CGLM_INLINE void glm_quat_lerp(versor from, versor to, float t, versor dest);
    CGLM_INLINE void glm_quat_slerp(versor q, versor r, float t, versor dest);
+   CGLM_INLINE void glm_quat_look(vec3 eye, versor ori, mat4 dest);
+   CGLM_INLINE void glm_quat_for(vec3 dir, vec3 fwd, vec3 up, versor dest);
+   CGLM_INLINE void glm_quat_forp(vec3 from,
+                                  vec3 to,
+                                  vec3 fwd,
+                                  vec3 up,
+                                  versor dest);
+   CGLM_INLINE void glm_quat_rotatev(versor q, vec3 v, vec3 dest);
+   CGLM_INLINE void glm_quat_rotate(mat4 m, versor q, mat4 dest);
  */
 
 #ifndef cglm_quat_h
@@ -46,6 +60,14 @@
 #  include "simd/sse2/quat.h"
 #endif
 
+CGLM_INLINE
+void
+glm_mat4_mulv(mat4 m, vec4 v, vec4 dest);
+
+CGLM_INLINE
+void
+glm_mat4_mul(mat4 m1, mat4 m2, mat4 dest);
+
 /*
  * IMPORTANT:
  * ----------------------------------------------------------------------------
@@ -603,10 +625,6 @@ glm_quat_slerp(versor from, versor to, float t, versor dest) {
   glm_vec4_scale(q1, 1.0f / sinTheta, dest);
 }
 
-CGLM_INLINE
-void
-glm_mat4_mulv(mat4 m, vec4 v, vec4 dest);
-
 /*!
  * @brief creates view matrix using quaternion as camera orientation
  *
@@ -677,7 +695,7 @@ glm_quat_forp(vec3 from, vec3 to, vec3 fwd, vec3 up, versor dest) {
 }
 
 /*!
- * @brief rotate existing transform matrix using quaternion
+ * @brief rotate vector using using quaternion
  *
  * @param[in]   q     quaternion
  * @param[in]   v     vector to rotate
@@ -704,4 +722,19 @@ glm_quat_rotatev(versor q, vec3 v, vec3 dest) {
   glm_vec_add(v1, v2, dest);
 }
 
+/*!
+ * @brief rotate existing transform matrix using quaternion
+ *
+ * @param[in]   m     existing transform matrix
+ * @param[in]   q     quaternion
+ * @param[out]  dest  destination matrix
+ */
+CGLM_INLINE
+void
+glm_quat_rotate(mat4 m, versor q, mat4 dest) {
+  mat4 rot;
+  glm_quat_mat4(q, rot);
+  glm_mat4_mul(m, rot, dest);
+}
+
 #endif /* cglm_quat_h */
diff --git a/src/mat4.c b/src/mat4.c
index 8b2a2d0..9407684 100644
--- a/src/mat4.c
+++ b/src/mat4.c
@@ -62,12 +62,6 @@ glmc_mat4_mulv(mat4 m, vec4 v, vec4 dest) {
   glm_mat4_mulv(m, v, dest);
 }
 
-CGLM_EXPORT
-void
-glmc_mat4_mulq(mat4 m, versor q, mat4 dest) {
-  glm_mat4_mulq(m, q, dest);
-}
-
 CGLM_EXPORT
 void
 glmc_mat4_quat(mat4 m, versor dest) {
diff --git a/test/src/test_quat.c b/test/src/test_quat.c
index 43dbdb2..fec8dae 100644
--- a/test/src/test_quat.c
+++ b/test/src/test_quat.c
@@ -154,5 +154,35 @@ test_quat(void **state) {
 
   test_assert_vec3_eq(v1, v2);
 
+  /* 11. test rotate transform */
+  glm_translate_make(rot1, (vec3){-10.0, 45.0f, 8.0f});
+  glm_rotate(rot1, glm_rad(-90), GLM_ZUP);
+
+  glm_quatv(q3, glm_rad(-90.0f), GLM_ZUP);
+  glm_translate_make(rot2, (vec3){-10.0, 45.0f, 8.0f});
+  glm_quat_rotate(rot2, q3, rot2);
+
+  /* result must be same (almost) */
+  test_assert_mat4_eq2(rot1, rot2, 0.000009);
+
+  glm_rotate_make(rot1, glm_rad(-90), GLM_ZUP);
+  glm_translate(rot1, (vec3){-10.0, 45.0f, 8.0f});
+
+  glm_quatv(q3, glm_rad(-90.0f), GLM_ZUP);
+  glm_mat4_identity(rot2);
+  glm_quat_rotate(rot2, q3, rot2);
+  glm_translate(rot2, (vec3){-10.0, 45.0f, 8.0f});
+
+  /* result must be same (almost) */
+  test_assert_mat4_eq2(rot1, rot2, 0.000009);
+
+  /* reverse */
+  glm_rotate_make(rot1, glm_rad(-90), GLM_ZUP);
+  glm_quatv(q3, glm_rad(90.0f), GLM_ZUP);
+  glm_quat_rotate(rot1, q3, rot1);
+
+  /* result must be identity */
+  test_assert_mat4_eq2(rot1, GLM_MAT4_IDENTITY, 0.000009);
+
   /* TODO: add tests for slerp, lerp */
 }