diff --git a/Cargo.toml b/Cargo.toml
index 97f9707..2e46180 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,7 +19,9 @@ path = "src/main.rs"
 
 [dependencies]
 async-trait = "0.1.62"
+bincode = "1.3.3"
 clap = { version = "4.1.1", features = ["derive"] }
+color-eyre = "0.6.2"
 crossterm = "0.25.0"
 dialoguer = "0.10.3"
 dirs = "4.0.0"
@@ -39,7 +41,7 @@ thiserror = "1.0.38"
 tokio = { version = "1.24.2", features = ["rt", "macros", "tracing", "net", "fs", "time", "process"] }
 toml = "0.5.11"
 tracing = "0.1.37"
-tracing-subscriber = "0.3.16"
+tracing-subscriber = { version = "0.3.16", features = ["env-filter"] }
 xkcd_unreachable = "0.1.1"
 zip = "0.6.3"
 
diff --git a/src/args.rs b/src/args.rs
index 716615e..41980e8 100644
--- a/src/args.rs
+++ b/src/args.rs
@@ -6,6 +6,10 @@ use clap::{Parser, Subcommand};
 #[derive(Clone, Debug, Parser)]
 #[clap(infer_subcommands = true)]
 pub struct Args {
+    /// Prints verbose logs
+    #[arg(long)]
+    pub verbose: bool,
+
     #[command(subcommand)]
     pub command: Command,
 }
diff --git a/src/consts.rs b/src/consts.rs
index 9aa99af..78765d4 100644
--- a/src/consts.rs
+++ b/src/consts.rs
@@ -14,7 +14,7 @@ lazy_static! {
         .unwrap_or_else(|| PathBuf::from(".cache"))
         .join(PathBuf::from("nenv"));
     pub static ref CFG_FILE_PATH: PathBuf = CFG_DIR.join("config.toml");
-    pub static ref VERSION_FILE_PATH: PathBuf = DATA_DIR.join("versions.json");
+    pub static ref VERSION_FILE_PATH: PathBuf = DATA_DIR.join("versions.cache");
     pub static ref BIN_DIR: PathBuf = DATA_DIR.join("bin");
     pub static ref NODE_VERSIONS_DIR: PathBuf = DATA_DIR.join("versions");
     pub static ref NODE_ARCHIVE_SUFFIX: String = format!("-{OS}-{ARCH}.{ARCHIVE_TYPE}");
diff --git a/src/error.rs b/src/error.rs
index 86356e8..dec3728 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -70,11 +70,11 @@ pub struct ParseJsonError {
 }
 
 #[derive(Debug, Error, Diagnostic)]
-#[diagnostic(code(nenv::json::serialize))]
-#[error("failed to serialize value to json string")]
-pub struct SerializeJsonError {
+#[diagnostic(code(nenv::bincode::serialize))]
+#[error("failed to serialize value to bincode")]
+pub struct SerializeBincodeError {
     #[from]
-    caused_by: serde_json::Error,
+    caused_by: bincode::Error,
 }
 
 #[derive(Debug, Error, Diagnostic)]
diff --git a/src/main.rs b/src/main.rs
index 42b9fbe..3569127 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -12,6 +12,8 @@ pub mod repository;
 mod utils;
 mod web_api;
 use miette::Result;
+use tracing::metadata::LevelFilter;
+use tracing_subscriber::fmt::format::FmtSpan;
 use xkcd_unreachable::xkcd_unreachable;
 
 mod args;
@@ -24,6 +26,10 @@ async fn main() -> Result<()> {
     miette::set_panic_hook();
     let args: Args = Args::parse();
 
+    if args.verbose {
+        init_tracing();
+    }
+
     if let args::Command::Version = &args.command {
         print_version();
         return Ok(());
@@ -56,3 +62,12 @@ fn print_version() {
 async fn get_nenv() -> Result<Nenv> {
     Nenv::init().await
 }
+
+fn init_tracing() {
+    tracing_subscriber::fmt::SubscriberBuilder::default()
+        .with_max_level(LevelFilter::DEBUG)
+        .with_writer(std::io::stderr)
+        .with_span_events(FmtSpan::NEW | FmtSpan::CLOSE)
+        .compact()
+        .init();
+}
diff --git a/src/mapper/mod.rs b/src/mapper/mod.rs
index bffa3d0..abb4075 100644
--- a/src/mapper/mod.rs
+++ b/src/mapper/mod.rs
@@ -21,6 +21,7 @@ impl Mapper {
         Self { node_path }
     }
     /// Executes a mapped command with the given node environment
+    #[tracing::instrument(level = "debug", skip(self))]
     pub async fn exec(&self, command: String, args: Vec<OsString>) -> Result<ExitStatus> {
         let executable = self.node_path.bin().join(&command);
         let exit_status = MappedCommand::new(command, executable, args).run().await?;
@@ -30,6 +31,7 @@ impl Mapper {
     }
 
     /// Recreates all environment mappings
+    #[tracing::instrument(level = "debug", skip(self))]
     pub async fn remap(&self) -> Result<()> {
         fs::remove_dir_all(&*BIN_DIR).await.into_diagnostic()?;
         fs::create_dir_all(&*BIN_DIR).await.into_diagnostic()?;
@@ -38,6 +40,7 @@ impl Mapper {
         Ok(())
     }
 
+    #[tracing::instrument(level = "debug", skip(self))]
     pub async fn remap_additive(&self) -> Result<()> {
         map_node_bin(&self.node_path).await?;
 
diff --git a/src/nenv.rs b/src/nenv.rs
index e5b80d0..640508f 100644
--- a/src/nenv.rs
+++ b/src/nenv.rs
@@ -20,6 +20,7 @@ pub struct Nenv {
 }
 
 impl Nenv {
+    #[tracing::instrument(level = "debug")]
     pub async fn init() -> Result<Self> {
         let config = ConfigAccess::load().await?;
         let repo = Repository::init(config.clone()).await?;
@@ -35,6 +36,7 @@ impl Nenv {
 
     /// Installs the given node version.
     /// Prompts if that version already exists
+    #[tracing::instrument(skip(self))]
     pub async fn install(&mut self, version: NodeVersion) -> Result<()> {
         Self::clear_version_cache().await?;
 
@@ -60,6 +62,7 @@ impl Nenv {
     }
 
     /// Sets the system-wide default version
+    #[tracing::instrument(skip(self))]
     pub async fn set_system_default(&mut self, version: NodeVersion) -> Result<()> {
         self.active_version = version.to_owned();
 
@@ -85,6 +88,7 @@ impl Nenv {
     }
 
     /// Executes a given node executable for the currently active version
+    #[tracing::instrument(skip(self))]
     pub async fn exec(&self, command: String, args: Vec<OsString>) -> Result<i32> {
         if !self.repo.is_installed(&self.active_version)? {
             self.repo.install_version(&self.active_version).await?;
@@ -94,18 +98,15 @@ impl Nenv {
         Ok(exit_status.code().unwrap_or(0))
     }
 
-    /// Persits all changes made that aren't written to the disk yet
-    pub async fn persist(&self) -> Result<()> {
-        self.config.save().await
-    }
-
     /// Clears the version cache and remaps all executables
+    #[tracing::instrument(skip(self))]
     pub async fn refresh(&self) -> Result<()> {
         Self::clear_version_cache().await?;
         self.get_mapper()?.remap().await
     }
 
     /// Lists the currently installed versions
+    #[tracing::instrument(skip(self))]
     pub async fn list_versions(&self) -> Result<()> {
         let versions = self.repo.installed_versions().await?;
         let active_version = self.repo.lookup_version(&self.active_version)?;
@@ -134,6 +135,13 @@ impl Nenv {
         Ok(())
     }
 
+    /// Persits all changes made that aren't written to the disk yet
+    #[tracing::instrument(level = "debug", skip(self))]
+    pub async fn persist(&self) -> Result<()> {
+        self.config.save().await
+    }
+
+    #[tracing::instrument(level = "debug")]
     async fn get_active_version() -> Option<NodeVersion> {
         version_detection::ParallelDetector::detect_version()
             .await
@@ -141,6 +149,7 @@ impl Nenv {
             .and_then(|v| v)
     }
 
+    #[tracing::instrument(level = "debug")]
     async fn clear_version_cache() -> Result<()> {
         if VERSION_FILE_PATH.exists() {
             fs::remove_file(&*VERSION_FILE_PATH)
@@ -151,6 +160,7 @@ impl Nenv {
         Ok(())
     }
 
+    #[tracing::instrument(level = "debug", skip(self))]
     fn get_mapper(&self) -> Result<Mapper> {
         let node_path = self
             .repo
diff --git a/src/repository/mod.rs b/src/repository/mod.rs
index ba520b2..2e28cb4 100644
--- a/src/repository/mod.rs
+++ b/src/repository/mod.rs
@@ -17,12 +17,15 @@ use crate::{
         ARCH, BIN_DIR, CACHE_DIR, CFG_DIR, DATA_DIR, NODE_ARCHIVE_SUFFIX, NODE_VERSIONS_DIR, OS,
     },
     error::VersionError,
-    web_api::{VersionInfo, WebApi},
+    web_api::WebApi,
 };
 
 use miette::{IntoDiagnostic, Result};
 
-use self::{node_path::NodePath, versions::Versions};
+use self::{
+    node_path::NodePath,
+    versions::{SimpleVersionInfo, Versions},
+};
 
 pub(crate) mod extract;
 pub(crate) mod node_path;
@@ -90,6 +93,7 @@ pub struct Repository {
 
 impl Repository {
     /// Initializes a new repository with the given confi
+    #[tracing::instrument(level = "debug", skip_all)]
     pub async fn init(config: ConfigAccess) -> Result<Self> {
         Self::create_folders().await?;
         let web_api = WebApi::new(&config.get().await.download.dist_base_url);
@@ -98,6 +102,7 @@ impl Repository {
         Ok(Self { web_api, versions })
     }
 
+    #[tracing::instrument(level = "debug")]
     async fn create_folders() -> Result<()> {
         let dirs = vec![
             &*CFG_DIR,
@@ -116,6 +121,7 @@ impl Repository {
     }
 
     /// Returns the path for the given node version
+    #[tracing::instrument(level = "debug", skip(self))]
     pub fn get_version_path(&self, version: &NodeVersion) -> Result<Option<NodePath>> {
         let info = self.lookup_version(version)?;
         let path = build_version_path(&info.version);
@@ -128,6 +134,7 @@ impl Repository {
     }
 
     /// Returns a list of installed versions
+    #[tracing::instrument(level = "debug", skip(self))]
     pub async fn installed_versions(&self) -> Result<Vec<Version>> {
         let mut versions = Vec::new();
         let mut iter = fs::read_dir(&*NODE_VERSIONS_DIR).await.into_diagnostic()?;
@@ -142,6 +149,7 @@ impl Repository {
     }
 
     /// Returns if the given version is installed
+    #[tracing::instrument(level = "debug", skip(self))]
     pub fn is_installed(&self, version: &NodeVersion) -> Result<bool> {
         let info = self.lookup_version(version)?;
 
@@ -149,7 +157,11 @@ impl Repository {
     }
 
     /// Performs a lookup for the given node version
-    pub fn lookup_version(&self, version_req: &NodeVersion) -> Result<&VersionInfo, VersionError> {
+    #[tracing::instrument(level = "debug", skip(self))]
+    pub fn lookup_version(
+        &self,
+        version_req: &NodeVersion,
+    ) -> Result<&SimpleVersionInfo, VersionError> {
         let version = match version_req {
             NodeVersion::Latest => self.versions.latest(),
             NodeVersion::LatestLts => self.versions.latest_lts(),
@@ -167,19 +179,22 @@ impl Repository {
     }
 
     /// Returns the reference to all known versions
+    #[tracing::instrument(level = "debug", skip(self))]
     pub fn all_versions(&self) -> &Versions {
         &self.versions
     }
 
     /// Installs a specified node version
+    #[tracing::instrument(level = "debug", skip(self))]
     pub async fn install_version(&self, version_req: &NodeVersion) -> Result<()> {
         let info = self.lookup_version(version_req)?;
         let archive_path = self.download_version(&info.version).await?;
-        self.extract_archive(info, &archive_path)?;
+        self.extract_archive(&info.version, &archive_path)?;
 
         Ok(())
     }
 
+    #[tracing::instrument(level = "debug", skip(self))]
     async fn download_version(&self, version: &Version) -> Result<PathBuf> {
         let download_path = CACHE_DIR.join(format!("node-v{}{}", version, *NODE_ARCHIVE_SUFFIX));
 
@@ -195,8 +210,9 @@ impl Repository {
         Ok(download_path)
     }
 
-    fn extract_archive(&self, info: &VersionInfo, archive_path: &Path) -> Result<()> {
-        let dst_path = NODE_VERSIONS_DIR.join(info.version.to_string());
+    #[tracing::instrument(level = "debug", skip(self))]
+    fn extract_archive(&self, version: &Version, archive_path: &Path) -> Result<()> {
+        let dst_path = NODE_VERSIONS_DIR.join(version.to_string());
         extract::extract_file(archive_path, &dst_path)?;
 
         Ok(())
@@ -204,6 +220,7 @@ impl Repository {
 }
 
 #[inline]
+#[tracing::instrument(level = "debug", skip_all)]
 async fn load_versions(web_api: &WebApi) -> Result<Versions> {
     let versions = if let Some(v) = Versions::load().await {
         v
diff --git a/src/repository/versions.rs b/src/repository/versions.rs
index 6edb555..a5b4fbd 100644
--- a/src/repository/versions.rs
+++ b/src/repository/versions.rs
@@ -1,17 +1,67 @@
-use std::collections::HashMap;
+use std::{collections::HashMap, fmt::Display};
 
 use semver::{Version, VersionReq};
 use serde::{Deserialize, Serialize};
+use std::fmt::Debug;
 use tokio::fs;
 
-use crate::{consts::VERSION_FILE_PATH, error::SerializeJsonError, web_api::VersionInfo};
-use miette::{IntoDiagnostic, Result};
+use crate::{consts::VERSION_FILE_PATH, error::SerializeBincodeError, web_api::VersionInfo};
+use miette::{Context, IntoDiagnostic, Result};
 
-#[derive(Clone, Debug, Serialize, Deserialize)]
+#[derive(Clone, Serialize, Deserialize)]
 pub struct Versions {
-    lts_versions: HashMap<String, VersionReq>,
-    versions: HashMap<Version, VersionInfo>,
-    sorted_versions: Vec<Version>,
+    lts_versions: HashMap<String, u16>,
+    versions: HashMap<SimpleVersion, SimpleVersionInfo>,
+    sorted_versions: Vec<SimpleVersion>,
+}
+
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug, Deserialize, Serialize, Hash)]
+pub struct SimpleVersion {
+    pub major: u16,
+    pub minor: u16,
+    pub patch: u32,
+}
+
+impl From<semver::Version> for SimpleVersion {
+    fn from(value: semver::Version) -> Self {
+        Self {
+            major: value.major as u16,
+            minor: value.minor as u16,
+            patch: value.patch as u32,
+        }
+    }
+}
+
+impl From<SimpleVersion> for semver::Version {
+    fn from(value: SimpleVersion) -> Self {
+        Self::new(value.major as u64, value.minor as u64, value.patch as u64)
+    }
+}
+
+impl Display for SimpleVersion {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let Self {
+            major,
+            minor,
+            patch,
+        } = self;
+        write!(f, "{major}.{minor}.{patch}")
+    }
+}
+
+#[derive(Clone, Serialize, Deserialize)]
+pub struct SimpleVersionInfo {
+    pub version: Version,
+    pub lts: Option<String>,
+}
+
+impl From<VersionInfo> for SimpleVersionInfo {
+    fn from(value: VersionInfo) -> Self {
+        Self {
+            version: value.version,
+            lts: value.lts.lts(),
+        }
+    }
 }
 
 impl Versions {
@@ -20,32 +70,34 @@ impl Versions {
         if !VERSION_FILE_PATH.exists() {
             return None;
         }
-        let versions_string = fs::read_to_string(&*VERSION_FILE_PATH).await.ok()?;
-        let versions = serde_json::from_str(&versions_string).ok()?;
-
-        Some(versions)
+        let byte_contents = fs::read(&*VERSION_FILE_PATH).await.ok()?;
+
+        match bincode::deserialize(&byte_contents) {
+            Ok(versions) => Some(versions),
+            Err(e) => {
+                tracing::error!("Failed to deserialize cache {e}");
+                fs::remove_file(&*VERSION_FILE_PATH).await.ok()?;
+                None
+            }
+        }
     }
 
     /// creates a new instance to access version information
+    #[tracing::instrument(level = "debug", skip_all)]
     pub fn new(all_versions: Vec<VersionInfo>) -> Self {
         let lts_versions = all_versions
             .iter()
-            .filter_map(|v| {
-                Some((
-                    v.lts.as_ref()?.to_lowercase(),
-                    VersionReq::parse(&format!("{}", v.version.major)).ok()?,
-                ))
-            })
+            .filter_map(|v| Some((v.lts.lts_ref()?.to_lowercase(), v.version.major as u16)))
             .collect::<HashMap<_, _>>();
         let mut sorted_versions = all_versions
             .iter()
-            .map(|v| v.version.to_owned())
+            .map(|v| v.version.to_owned().into())
             .collect::<Vec<_>>();
         sorted_versions.sort();
 
         let versions = all_versions
             .into_iter()
-            .map(|v| (v.version.to_owned(), v))
+            .map(|v| (v.version.to_owned().into(), v.into()))
             .collect::<HashMap<_, _>>();
 
         Self {
@@ -55,52 +107,74 @@ impl Versions {
         }
     }
 
+    #[tracing::instrument(level = "debug", skip_all)]
     pub(crate) async fn save(&self) -> Result<()> {
-        let json_string = serde_json::to_string(&self).map_err(SerializeJsonError::from)?;
-        fs::write(&*VERSION_FILE_PATH, json_string)
+        let byte_content = bincode::serialize(self).map_err(SerializeBincodeError::from)?;
+        fs::write(&*VERSION_FILE_PATH, byte_content)
             .await
-            .into_diagnostic()?;
+            .into_diagnostic()
+            .context("Caching available node version.")?;
 
         Ok(())
     }
 
     /// Returns the latest known node version
-    pub fn latest(&self) -> &VersionInfo {
+    #[tracing::instrument(level = "debug", skip_all)]
+    pub fn latest(&self) -> &SimpleVersionInfo {
         self.versions
             .get(self.sorted_versions.last().expect("No known node versions"))
             .unwrap()
     }
 
     /// Returns the latest node lts version
-    pub fn latest_lts(&self) -> &VersionInfo {
+    #[tracing::instrument(level = "debug", skip_all)]
+    pub fn latest_lts(&self) -> &SimpleVersionInfo {
         let mut versions = self
             .lts_versions
             .values()
-            .filter_map(|req| self.get_fulfilling(req))
+            .filter_map(|req| self.get_latest_for_major(*req))
             .collect::<Vec<_>>();
         versions.sort_by_key(|v| &v.version);
         versions.last().expect("No known lts node versions")
     }
 
     /// Returns a lts version by name
-    pub fn get_lts<S: AsRef<str>>(&self, lts_name: S) -> Option<&VersionInfo> {
+    #[tracing::instrument(level = "debug", skip(self))]
+    pub fn get_lts<S: AsRef<str> + Debug>(&self, lts_name: S) -> Option<&SimpleVersionInfo> {
         let lts_version = self.lts_versions.get(lts_name.as_ref())?;
-        self.get_fulfilling(lts_version)
+        self.get_latest_for_major(*lts_version)
     }
 
     /// Returns any version that fulfills the given requirement
-    pub fn get_fulfilling(&self, req: &VersionReq) -> Option<&VersionInfo> {
+    #[tracing::instrument(level = "debug", skip(self))]
+    pub fn get_fulfilling(&self, req: &VersionReq) -> Option<&SimpleVersionInfo> {
         let fulfilling_versions = self
             .sorted_versions
             .iter()
+            .map(|v| (*v).into())
             .filter(|v| req.matches(v))
             .collect::<Vec<_>>();
 
-        self.versions.get(fulfilling_versions.last()?)
+        let version = fulfilling_versions.last()?.clone().into();
+        self.versions.get(&version).into()
     }
 
     /// Returns the info for the given version
-    pub fn get(&self, version: &Version) -> Option<&VersionInfo> {
-        self.versions.get(version)
+    #[tracing::instrument(level = "debug", skip(self))]
+    pub fn get(&self, version: &Version) -> Option<&SimpleVersionInfo> {
+        self.versions.get(&version.clone().into())
+    }
+
+    /// Returns any version that fulfills the given requirement
+    #[tracing::instrument(level = "debug", skip(self))]
+    fn get_latest_for_major(&self, major: u16) -> Option<&SimpleVersionInfo> {
+        let fulfilling_versions = self
+            .sorted_versions
+            .iter()
+            .filter(|v| v.major == major)
+            .collect::<Vec<_>>();
+
+        let version = fulfilling_versions.last()?;
+        self.versions.get(&version).into()
     }
 }
diff --git a/src/web_api/mod.rs b/src/web_api/mod.rs
index 502c3eb..beac43d 100644
--- a/src/web_api/mod.rs
+++ b/src/web_api/mod.rs
@@ -42,7 +42,7 @@ impl WebApi {
     }
 
     /// Returns the list of available node versions
-    #[tracing::instrument(level = "trace")]
+    #[tracing::instrument(level = "debug")]
     pub async fn get_versions(&self) -> Result<Vec<VersionInfo>> {
         let versions = self
             .client
@@ -61,7 +61,7 @@ impl WebApi {
 
     /// Downloads a specific node version
     /// and writes it to the given writer
-    #[tracing::instrument(level = "trace", skip(writer))]
+    #[tracing::instrument(level = "debug", skip(writer))]
     pub async fn download_version<W: AsyncWrite + Unpin, S: Display + Debug>(
         &self,
         version: S,
diff --git a/src/web_api/model.rs b/src/web_api/model.rs
index d66f57f..e5f3649 100644
--- a/src/web_api/model.rs
+++ b/src/web_api/model.rs
@@ -1,49 +1,52 @@
-use std::borrow::Cow;
-
-use serde::{Deserialize, Deserializer, Serialize};
+use serde::{Deserialize, Deserializer};
 
 /// Represents a single nodejs version info entry
 /// as retrieved from nodejs.org
-#[derive(Clone, Debug, Deserialize, Serialize)]
+#[derive(Clone, Debug, Deserialize)]
 pub struct VersionInfo {
     #[serde(deserialize_with = "deserialize_prefixed_version")]
     pub version: semver::Version,
     pub date: String,
     pub modules: Option<String>,
 
-    #[serde(deserialize_with = "deserialize_false_as_none")]
-    pub lts: Option<String>,
+    pub lts: LtsInfo,
     pub security: bool,
-    #[serde(flatten)]
-    pub module_versions: ModuleVersions,
-    pub files: Vec<String>,
-}
-
-#[derive(Clone, Debug, Deserialize, Serialize)]
-pub struct ModuleVersions {
     pub v8: String,
     pub npm: Option<String>,
     pub uv: Option<String>,
     pub zlib: Option<String>,
     pub openssl: Option<String>,
+    pub files: Vec<String>,
 }
 
-fn deserialize_false_as_none<'de, D: Deserializer<'de>>(
-    deserializer: D,
-) -> Result<Option<String>, D::Error> {
-    Ok(String::deserialize(deserializer).ok())
+#[derive(Clone, Debug, Deserialize)]
+#[serde(untagged)]
+pub enum LtsInfo {
+    Version(String),
+    NotLts(bool),
+}
+
+impl LtsInfo {
+    pub fn lts(self) -> Option<String> {
+        match self {
+            LtsInfo::Version(v) => Some(v),
+            LtsInfo::NotLts(_) => None,
+        }
+    }
+    pub fn lts_ref(&self) -> Option<&String> {
+        match &self {
+            LtsInfo::Version(v) => Some(v),
+            LtsInfo::NotLts(_) => None,
+        }
+    }
 }
 
 fn deserialize_prefixed_version<'de, D: Deserializer<'de>>(
     deserializer: D,
 ) -> Result<semver::Version, D::Error> {
     let version = String::deserialize(deserializer)?;
-    let version = if let Some(v) = version.strip_prefix('v') {
-        Cow::Borrowed(v)
-    } else {
-        Cow::Owned(version)
-    };
-    let version = semver::Version::parse(version.as_ref()).map_err(serde::de::Error::custom)?;
+    let version = semver::Version::parse(version.trim_start_matches('v'))
+        .map_err(serde::de::Error::custom)?;
 
     Ok(version)
 }