diff --git a/DESCRIPTION b/DESCRIPTION
index f57d080..de4c660 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -22,7 +22,7 @@ Depends:
 Imports:
     dplyr,
     purrr,
-    rstan (>= 2.21.2),
+    rstan (>= 2.26.0),
     rstantools (>= 2.1.1),
     stringr,
     tidyr,
@@ -38,8 +38,8 @@ Suggests:
   parallelly,
   rmarkdown
 LinkingTo: 
-    StanHeaders, 
-    rstan, 
+    StanHeaders (>= 2.26.0), 
+    rstan (>= 2.26.0), 
     BH (>= 1.72),
     Rcpp,
     RcppEigen
diff --git a/configure b/configure
new file mode 100755
index 0000000..0304fc5
--- /dev/null
+++ b/configure
@@ -0,0 +1,5 @@
+#! /bin/sh
+
+# Generated by rstantools.  Do not edit by hand.
+
+"${R_HOME}/bin/Rscript" -e "rstantools::rstan_config()"
diff --git a/configure.win b/configure.win
new file mode 100755
index 0000000..5e2dceb
--- /dev/null
+++ b/configure.win
@@ -0,0 +1,5 @@
+#! /bin/sh
+
+# Generated by rstantools.  Do not edit by hand.
+
+"${R_HOME}/bin${R_ARCH_BIN}/Rscript.exe" -e "rstantools::rstan_config()"
diff --git a/inst/stan/breath_test_1.stan b/inst/stan/breath_test_1.stan
index 24b9b76..6343ef9 100644
--- a/inst/stan/breath_test_1.stan
+++ b/inst/stan/breath_test_1.stan
@@ -5,7 +5,7 @@ data{
   int<lower=0> n_record; // Number of records
   int<lower=1> student_t_df; // using Gaussian for student_t_df >= 10
   real<lower=0> dose;
-  int<lower=0> pat_group_i[n];
+  array[n] int<lower=0> pat_group_i;
   vector<lower=0>[n] minute;
   vector<lower=-30>[n] pdr;
 }