I have two laptops with relatively good specifications that I use for running Bayesian models, both have up-to-date software and correctly specified stan installation. Stan, brms and rstanarm models compile well. However, when I specify my rstanarm survival models with time-varying (tve()) argument, the running of chains hangs or never ends. No errors are shown.

**What may be the problem and how to solve this?**

**Reproducible example**, including data that will be downloaded with code and its continuous variables are already centered.

```
#data
library(tidyverse)
data = read_delim("https://www.dropbox.com/s/ufpmejd6do8saq6/shared_data.csv?dl=1", ";", escape_double = FALSE, trim_ws = TRUE)
#model
library(rstanarm)
options(mc.cores = parallel::detectCores())
m1 = stan_surv(formula = Surv(time, status) ~ p1 + p2 + tve(p3) + p4, basehaz = "ms", basehaz_ops = list(df = 8), data = data)
```

**PS!** stan_surv() is a function from rstanarm packageâ€™s survival branch, following code should be used for its installation (GitHub - stan-dev/rstanarm: rstanarm R package for Bayesian applied regression modeling):

```
install.packages("rstanarm", repos = c("https://mc-stan.org/r-packages/", getOption("repos")))
```

if the last one didnâ€™t work, causing R to crash, this one helps (Stan_surv crashes R repeatedly - #13 by binman):

remove.packages(c(â€śStanHeadersâ€ť, â€śrstanâ€ť))

install.packages(â€śStanHeadersâ€ť, repos = c(â€śRepository for distributing (some) stan-dev R packages | r-packagesâ€ť, getOption(â€śreposâ€ť)))

install.packages(â€śrstanâ€ť, repos = c(â€śRepository for distributing (some) stan-dev R packages | r-packagesâ€ť, getOption(â€śreposâ€ť)))