diff --git a/vignettes/small_model_workflow/combined_first.stan b/vignettes/small_model_workflow/combined_first.stan
index 791b0ba..fe95c00 100644
--- a/vignettes/small_model_workflow/combined_first.stan
+++ b/vignettes/small_model_workflow/combined_first.stan
@@ -1,6 +1,6 @@
 data {
   int<lower=0> N_obs;
-  int y[N_obs];
+  array[N_obs] int y;
 
   int<lower=1> N_predictors;
   matrix[N_predictors, N_obs] x;
diff --git a/vignettes/small_model_workflow/mixture_first.stan b/vignettes/small_model_workflow/mixture_first.stan
index 3d780b5..cf94bf0 100644
--- a/vignettes/small_model_workflow/mixture_first.stan
+++ b/vignettes/small_model_workflow/mixture_first.stan
@@ -1,6 +1,6 @@
 data {
   int<lower=0> N;
-  int y[N];
+  array[N] int y;
 }
 
 parameters {
diff --git a/vignettes/small_model_workflow/mixture_fixed_log_mix.stan b/vignettes/small_model_workflow/mixture_fixed_log_mix.stan
index df919be..14e912e 100644
--- a/vignettes/small_model_workflow/mixture_fixed_log_mix.stan
+++ b/vignettes/small_model_workflow/mixture_fixed_log_mix.stan
@@ -1,6 +1,6 @@
 data {
   int<lower=0> N;
-  int y[N];
+  array[N] int y;
 }
 
 parameters {
diff --git a/vignettes/small_model_workflow/mixture_fixed_ordered.stan b/vignettes/small_model_workflow/mixture_fixed_ordered.stan
index 6832c3a..0c96cc4 100644
--- a/vignettes/small_model_workflow/mixture_fixed_ordered.stan
+++ b/vignettes/small_model_workflow/mixture_fixed_ordered.stan
@@ -1,6 +1,6 @@
 data {
   int<lower=0> N;
-  int y[N];
+  array[N] int y;
 }
 
 parameters {