diff --git a/swh/fuse/cache.py b/swh/fuse/cache.py
--- a/swh/fuse/cache.py
+++ b/swh/fuse/cache.py
@@ -209,7 +209,7 @@
             try:
                 history.append(parse_swhid(parent))
             except ValidationError:
-                logging.warning(f"Cannot parse object from history cache: {parent}")
+                logging.warning("Cannot parse object from history cache: %s", parent)
         return history
 
     async def set(self, history: str) -> None:
@@ -265,7 +265,7 @@
     def __init__(self, conf: Dict[str, Any]):
         m = re.match(r"(\d+)\s*(.+)\s*", conf["maxram"])
         if not m:
-            logging.error(f"Cannot parse direntry maxram config: {conf['maxram']}")
+            logging.error("Cannot parse direntry maxram config: %s", conf["maxram"])
             sys.exit(1)
 
         num = float(m.group(1))
diff --git a/swh/fuse/cli.py b/swh/fuse/cli.py
--- a/swh/fuse/cli.py
+++ b/swh/fuse/cli.py
@@ -62,7 +62,7 @@
         config_file = DEFAULT_CONFIG_PATH
 
     try:
-        logging.info(f"Loading configuration from: {config_file}")
+        logging.info("Loading configuration from: %s", config_file)
         conf = config.read_raw_config(config.config_basepath(config_file))
         if not conf:
             raise ValueError(f"Cannot parse configuration file: {config_file}")
@@ -76,10 +76,10 @@
         # recursive merge not done by config.read
         conf = config.merge_configs(DEFAULT_CONFIG, conf)
     except Exception as err:
-        logging.warning(f"Using default configuration (cannot load custom one: {err})")
+        logging.warning("Using default configuration (cannot load custom one: %s)", err)
         conf = DEFAULT_CONFIG
 
-    logging.info(f"Read configuration: \n{pprint.pformat(conf)}")
+    logging.info("Read configuration: \n%s", pprint.pformat(conf))
     ctx.ensure_object(dict)
     ctx.obj["config"] = conf
 
@@ -177,8 +177,9 @@
         subprocess.run(["fusermount", "-u", path], check=True)
     except subprocess.CalledProcessError as err:
         logging.error(
-            f"cannot unmount virtual file system: "
-            f"\"{' '.join(err.cmd)}\" returned exit status {err.returncode}"
+            "cannot unmount virtual file system: '%s' returned exit status %d",
+            " ".join(err.cmd),
+            err.returncode,
         )
         ctx.exit(1)
 
diff --git a/swh/fuse/fuse.py b/swh/fuse/fuse.py
--- a/swh/fuse/fuse.py
+++ b/swh/fuse/fuse.py
@@ -85,7 +85,7 @@
             # Retrieve it from cache so it is correctly typed
             return await self.cache.metadata.get(swhid)
         except requests.HTTPError as err:
-            logging.error(f"Cannot fetch metadata for object {swhid}: {err}")
+            logging.error("Cannot fetch metadata for object %s: %s", swhid, err)
             raise
 
     async def get_blob(self, swhid: SWHID) -> bytes:
@@ -109,7 +109,7 @@
             await self.cache.blob.set(swhid, blob)
             return blob
         except requests.HTTPError as err:
-            logging.error(f"Cannot fetch blob for object {swhid}: {err}")
+            logging.error("Cannot fetch blob for object %s: %s", swhid, err)
             raise
 
     async def get_history(self, swhid: SWHID) -> List[SWHID]:
@@ -129,7 +129,7 @@
             # Retrieve it from cache so it is correctly typed
             return await self.cache.history.get(swhid)
         except requests.HTTPError as err:
-            logging.error(f"Cannot fetch history for object {swhid}: {err}")
+            logging.error("Cannot fetch history for object %s: %s", swhid, err)
             # Ignore exception since swh-graph does not necessarily contain the
             # most recent artifacts from the archive. Computing the full history
             # from the Web API is too computationally intensive so simply return
@@ -184,7 +184,7 @@
                 next_id += 1
                 self._inode2entry[attrs.st_ino] = entry
         except Exception as err:
-            logging.exception(f"Cannot readdir: {err}")
+            logging.exception("Cannot readdir: %s", err)
             raise pyfuse3.FUSEError(errno.ENOENT)
 
     async def open(
@@ -207,7 +207,7 @@
             data = await entry.get_content()
             return data[offset : offset + length]
         except Exception as err:
-            logging.exception(f"Cannot read: {err}")
+            logging.exception("Cannot read: %s", err)
             raise pyfuse3.FUSEError(errno.ENOENT)
 
     async def lookup(
@@ -225,7 +225,7 @@
             else:
                 raise ValueError(f"unknown name: {name}")
         except Exception as err:
-            logging.exception(f"Cannot lookup: {err}")
+            logging.exception("Cannot lookup: %s", err)
             raise pyfuse3.FUSEError(errno.ENOENT)
 
     async def readlink(self, inode: int, _ctx: pyfuse3.RequestContext) -> bytes:
@@ -248,7 +248,7 @@
             try:
                 await fs.get_metadata(swhid)
             except Exception as err:
-                logging.exception(f"Cannot prefetch object {swhid}: {err}")
+                logging.exception("Cannot prefetch object %s: %s", swhid, err)
 
         fuse_options = set(pyfuse3.default_options)
         fuse_options.add("fsname=swhfs")
@@ -259,7 +259,7 @@
             pyfuse3.init(fs, root_path, fuse_options)
             await pyfuse3.main()
         except Exception as err:
-            logging.error(f"Error running FUSE: {err}")
+            logging.error("Error running FUSE: %s", err)
         finally:
             fs.shutdown()
             pyfuse3.close(unmount=True)