diff --git a/.gitignore b/.gitignore
index ea8c4bf7f..40d9acab9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 /target
+/.idea
\ No newline at end of file
diff --git a/Cargo.lock b/Cargo.lock
index bbd070f20..5644a9279 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -932,6 +932,7 @@ dependencies = [
  "rusqlite",
  "sieve-cache",
  "sqlite3-parser",
+ "thiserror",
 ]
 
 [[package]]
diff --git a/core/Cargo.toml b/core/Cargo.toml
index 7310fa6c0..3012d8273 100644
--- a/core/Cargo.toml
+++ b/core/Cargo.toml
@@ -30,6 +30,7 @@ fallible-iterator = "0.3.0"
 log = "0.4.20"
 sieve-cache = "0.1.4"
 sqlite3-parser = "0.11.0"
+thiserror = "1.0.61"
 
 [target.'cfg(not(target_family = "windows"))'.dev-dependencies]
 pprof = { version = "0.12.1", features = ["criterion", "flamegraph"] }
diff --git a/core/pager.rs b/core/pager.rs
index c8275bb48..c2b29574b 100644
--- a/core/pager.rs
+++ b/core/pager.rs
@@ -140,8 +140,7 @@ impl Pager {
             self.buffer_pool.clone(),
             page.clone(),
             page_idx,
-        )
-        .unwrap();
+        )?;
         page_cache.insert(page_idx, page.clone());
         Ok(page)
     }
diff --git a/core/storage.rs b/core/storage.rs
index 1086e3274..41e430f91 100644
--- a/core/storage.rs
+++ b/core/storage.rs
@@ -4,8 +4,15 @@ use crate::{
     io::{Completion, WriteCompletion},
     Buffer,
 };
-use anyhow::Result;
+use anyhow::{ensure, Result};
 use std::{cell::RefCell, rc::Rc};
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum StorageError {
+    #[error("file is not a database")]
+    NotADB,
+}
 
 pub struct PageSource {
     io: Rc<dyn PageIO>,
@@ -63,12 +70,10 @@ struct FileStorage {
 #[cfg(feature = "fs")]
 impl PageIO for FileStorage {
     fn get(&self, page_idx: usize, c: Rc<Completion>) -> Result<()> {
-        let page_size = c.buf().len();
+        let size = c.buf().len();
         assert!(page_idx > 0);
-        assert!(page_size >= 512);
-        assert!(page_size <= 65536);
-        assert!((page_size & (page_size - 1)) == 0);
-        let pos = (page_idx - 1) * page_size;
+        ensure!(size >= 1 << 9 && size <= 1 << 16 && size & (size - 1) == 0, StorageError::NotADB);
+        let pos = (page_idx - 1) * size;
         self.file.pread(pos, c)?;
         Ok(())
     }