diff --git a/.bumpversion.toml b/.bumpversion.toml
index 0971522..26e90be 100644
--- a/.bumpversion.toml
+++ b/.bumpversion.toml
@@ -1,4 +1,4 @@
-current_version = "1.1.1"
+current_version = "1.0.0"
 commit = true
 tag = true
 message = "chore: bump {current_version} → {new_version}"
@@ -11,8 +11,8 @@ type = "string"
 values = ["alpha", "beta", "stable"]
 
 [file."Cargo.toml"]
-formats = ['version = "{version}"']
+format = 'version = "{version}"'
 
 [file."Cargo.lock"]
-formats = ["""name = "bump2version"
-version = "{version}""""]
+format = """name = "bump2version"
+version = "{version}""""
diff --git a/Cargo.lock b/Cargo.lock
index 63177c3..f5f2424 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -61,7 +61,7 @@ dependencies = [
 
 [[package]]
 name = "bump2version"
-version = "1.1.1"
+version = "1.0.0"
 dependencies = [
  "clap",
  "regex",
diff --git a/Cargo.toml b/Cargo.toml
index 5a74359..73bdd09 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "bump2version"
-version = "1.1.1"
+version = "1.0.0"
 edition = "2021"
 description = "⬆️ Easily manage version numbers in your projects."
 license = "MIT"
@@ -13,6 +13,10 @@ authors = [
   "TECHNOFAB <admin@technofab.de>",
 ]
 
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[lib]
+crate-type = ["cdylib"]
+
 [dependencies]
 clap = { version = "4.5.1", features = ["derive"] }
 regex = "1.10.3"
diff --git a/src/cli.rs b/src/cli.rs
old mode 100644
new mode 100755
index f07903f..cf8a99c
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -24,10 +24,6 @@ pub(crate) struct Cli {
     #[arg(short = 'n', long = "dry-run", default_value_t = false)]
     pub(crate) dry_run: bool,
 
-    /// Current version
-    #[arg(long = "current-version", value_name = "VERSION")]
-    pub(crate) current_version: Option<String>,
-
     /// New version that should be in the files.
     #[arg(long = "new-version", value_name = "VERSION")]
     pub(crate) new_version: Option<String>,
diff --git a/src/config.rs b/src/config.rs
index a2e0e1d..3da1183 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -4,7 +4,7 @@ use serde_derive::Deserialize;
 
 #[derive(Debug, Clone, Deserialize)]
 pub(crate) struct Config {
-    pub(crate) current_version: Option<String>,
+    pub(crate) current_version: String,
     pub(crate) message: Option<String>,
     pub(crate) commit: bool,
     pub(crate) tag: bool,
@@ -13,8 +13,8 @@ pub(crate) struct Config {
     #[serde(default = "default_serialize")]
     pub(crate) serialize: String,
 
-    pub(crate) part: Option<HashMap<String, Part>>,
-    pub(crate) file: Option<HashMap<String, File>>,
+    pub(crate) part: HashMap<String, Part>,
+    pub(crate) file: HashMap<String, File>,
 }
 
 #[derive(Debug, Clone, Deserialize)]
@@ -35,8 +35,8 @@ pub(crate) struct Part {
 
 #[derive(Debug, Clone, Deserialize)]
 pub(crate) struct File {
-    /// Formats to replace, eg. `current_version = "{version}"`
-    pub(crate) formats: Vec<String>,
+    /// Format to replace, eg. `current_version = "{version}"`
+    pub(crate) format: String,
 }
 
 fn default_parse() -> String {
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..022eb5e
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,6 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+
+pub(crate) mod cli;
+pub(crate) mod config;
+pub(crate) mod utils;
diff --git a/src/main.rs b/src/main.rs
index 45903fd..ace6f87 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -38,23 +38,12 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         }
     };
 
-    let current_version = args
-        .current_version
+    let current_version = config.current_version.clone();
+
+    let attempted_new_version = args
+        .new_version
         .clone()
-        .or(config.current_version.clone());
-
-    if current_version.is_none() {
-        error!("No current version could be determined, either set in config or pass as arg");
-        exit(1);
-    }
-
-    let current_version = current_version.unwrap();
-
-    let attempted_new_version = args.new_version.clone().or(attempt_version_bump(
-        args.clone(),
-        config.clone(),
-        current_version.clone(),
-    ));
+        .or(attempt_version_bump(args.clone(), config.clone()));
 
     if attempted_new_version.is_some() {
         let new_version = attempted_new_version.clone().unwrap();
@@ -68,8 +57,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
             .or(config.message)
             .unwrap_or("Bump version: {current_version} → {new_version}".to_string());
 
-        let config_files = config.file.unwrap_or_default();
-        let files: Vec<&String> = config_files.keys().collect();
+        let files: Vec<&String> = config.file.keys().collect();
 
         // Check if Git working directory is clean
         if fs::metadata(".git").is_ok() {
@@ -95,24 +83,22 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         // Update version in specified files
         info!(amount = &files.len(), "Updating version in files");
         for path in files.clone() {
-            let mut content = fs::read_to_string(path)?;
-            let formats = &config_files.get(path).unwrap().formats.clone();
+            let content = fs::read_to_string(path)?;
+            let format = &config.file.get(path).unwrap().format;
 
-            for format in formats {
-                let old_line = format.replace("{version}", &current_version);
-                if !content.contains(&old_line) {
-                    warn!(
-                        current_version,
-                        path, "Did not find current version in file"
-                    );
-                }
-
-                let new_line = format.replace("{version}", &new_version);
-                content = content.replace(&old_line, &new_line);
+            let old_line = format.replace("{version}", &current_version);
+            if !content.contains(&old_line) {
+                warn!(
+                    current_version,
+                    path, "Did not find current version in file"
+                );
             }
 
+            let new_line = format.replace("{version}", &new_version);
+            let updated_content = content.replace(&old_line, &new_line);
+
             if !dry_run {
-                fs::write(path, content)?;
+                fs::write(path, updated_content)?;
             }
         }
 
diff --git a/src/utils.rs b/src/utils.rs
index 15d0606..7e31e12 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -6,11 +6,7 @@ use std::collections::HashMap;
 use std::ops::Index;
 use tracing::{error, trace};
 
-pub(crate) fn attempt_version_bump(
-    args: Cli,
-    config: Config,
-    current_version: String,
-) -> Option<String> {
+pub fn attempt_version_bump(args: Cli, config: Config) -> Option<String> {
     let parse_regex = config.parse;
     let regex = match Regex::new(&parse_regex) {
         Ok(r) => r,
@@ -20,6 +16,7 @@ pub(crate) fn attempt_version_bump(
         }
     };
 
+    let current_version = config.current_version;
     let mut parsed: HashMap<String, String> = HashMap::new();
 
     if let Some(captures) = regex.captures(&current_version) {
@@ -44,7 +41,7 @@ pub(crate) fn attempt_version_bump(
 
     for label in order.clone() {
         if let Some(part) = parsed.get_mut(label) {
-            let part_cfg = part_configs.as_ref().and_then(|c| c.get(label));
+            let part_cfg = part_configs.get(label);
 
             if label == args.bump {
                 match part_cfg