diff --git a/server/src/main.rs b/server/src/main.rs
index d4149b6c..13fc08a1 100644
--- a/server/src/main.rs
+++ b/server/src/main.rs
@@ -12,10 +12,11 @@ use rayon_core::ThreadPoolBuilder;
 use sparesults::{QueryResultsFormat, QueryResultsSerializer};
 use std::cell::RefCell;
 use std::cmp::{max, min};
+use std::ffi::OsStr;
 use std::fmt;
 use std::fs::File;
 use std::io::{self, BufReader, Error, ErrorKind, Read, Write};
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::rc::Rc;
 use std::str::FromStr;
 use std::thread::available_parallelism;
@@ -52,7 +53,7 @@ enum Command {
         ///
         /// If multiple files are provided they are loaded in parallel.
         #[arg(short, long, global = true, num_args = 0..)]
-        file: Vec<String>,
+        file: Vec<PathBuf>,
         /// Attempt to keep loading even if the data file is invalid.
         ///
         /// Only works with N-Triples and N-Quads for now.
@@ -79,7 +80,6 @@ pub fn main() -> io::Result<()> {
                 .scope(|s| {
                     for file in file {
                         let store = store.clone();
-                        let file = file.to_string();
                         s.spawn(move |_| {
                             let f = file.clone();
                             let start = Instant::now();
@@ -90,35 +90,39 @@ pub fn main() -> io::Result<()> {
                                     size,
                                     elapsed.as_secs(),
                                     ((size as f64) / elapsed.as_secs_f64()).round(),
-                                    f
+                                    f.display()
                                 )
                             });
                             if lenient {
                                 let f = file.clone();
                                 loader = loader.on_parse_error(move |e| {
-                                    eprintln!("Parsing error on file {}: {}", f, e);
+                                    eprintln!("Parsing error on file {}: {}", f.display(), e);
                                     Ok(())
                                 })
                             }
                             let fp = match File::open(&file) {
                                 Ok(fp) => fp,
                                 Err(error) => {
-                                    eprintln!("Error while opening file {}: {}", file, error);
+                                    eprintln!(
+                                        "Error while opening file {}: {}",
+                                        file.display(),
+                                        error
+                                    );
                                     return;
                                 }
                             };
                             if let Err(error) = {
-                                if file.ends_with(".gz") {
+                                if file.extension().map_or(false, |e| e == OsStr::new("gz")) {
                                     bulk_load(
                                         loader,
-                                        &file[..file.len() - 3],
                                         MultiGzDecoder::new(fp),
+                                        &file.with_extension(""),
                                     )
                                 } else {
-                                    bulk_load(loader, &file, fp)
+                                    bulk_load(loader, fp, &file)
                                 }
                             } {
-                                eprintln!("Error while loading file {}: {}", file, error)
+                                eprintln!("Error while loading file {}: {}", file.display(), error)
                             }
                         })
                     }
@@ -138,10 +142,10 @@ pub fn main() -> io::Result<()> {
     }
 }
 
-fn bulk_load(loader: BulkLoader, file: &str, reader: impl Read) -> io::Result<()> {
-    let (_, extension) = file.rsplit_once('.').ok_or_else(|| Error::new(
+fn bulk_load(loader: BulkLoader, reader: impl Read, file: &Path) -> io::Result<()> {
+    let extension = file.extension().and_then(|extension| extension.to_str()).ok_or_else(|| Error::new(
         ErrorKind::InvalidInput,
-        format!("The server is not able to guess the file format of {} because the file name as no extension", file)))?;
+        format!("The server is not able to guess the file format of {} because the file name as no extension", file.display())))?;
     let reader = BufReader::new(reader);
     if let Some(format) = DatasetFormat::from_extension(extension) {
         loader.load_dataset(reader, format, None)?;