diff --git a/Cargo.lock b/Cargo.lock
index 2389b90..887b604 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -213,6 +213,26 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "thiserror"
+version = "2.0.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4288b5bcbc7920c07a1149a35cf9590a2aa808e0bc1eafaade0b80947865fbc4"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "2.0.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ebc4ee7f67670e9b64d05fa4253e753e016c6c95ff35b89b7941d6b856dec1d5"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "toml"
 version = "1.0.6+spec-1.1.0"
@@ -264,6 +284,7 @@ version = "0.1.0"
 dependencies = [
  "notify",
  "serde",
+ "thiserror",
  "toml",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index a430fc6..46ae1d1 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,4 +6,5 @@ edition = "2024"
 [dependencies]
 notify = "8.2.0"
 serde = { version = "1.0.228", features = ["derive"] }
+thiserror = "2.0.18"
 toml = "1.0.6"
diff --git a/src/main.rs b/src/main.rs
index 0ca9764..b003588 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,34 +1,94 @@
 use std::{
-    env,
-    path::{Path, PathBuf},
+    env, fs,
+    path::{self, Path, PathBuf},
     sync::mpsc,
 };
 
-use notify::{Event, RecursiveMode, Result, Watcher};
-use serde::Deserialize;
+use notify::{Event, EventKind, RecursiveMode, Watcher, event::CreateKind};
+use serde::{Deserialize, Serialize};
+use thiserror::Error;
 
-#[derive(Debug, Deserialize)]
+#[derive(Debug, Deserialize, Serialize)]
 struct Config {
-    libraries: LibConfig,
+    libraries: Option<LibConfig>,
 }
 
-impl Config {}
+impl Config {
+    fn load_or_create() -> Result<Self, ConfigError> {
+        let config_path =
+            PathBuf::from(env::var("HOME").unwrap()).join(".config/uniloader/config.toml");
 
-#[derive(Debug, Deserialize)]
+        if config_path.exists() {
+            let contents = fs::read_to_string(&config_path).map_err(|_| ConfigError::ConfigErr)?;
+            let config: Config = toml::from_str(&contents).map_err(|_| ConfigError::ConfigErr)?;
+            Ok(config)
+        } else {
+            fs::create_dir_all(config_path.parent().unwrap())
+                .map_err(|_| ConfigError::ConfigErr)?;
+            let config = Config { libraries: None };
+            let contents = toml::to_string_pretty(&config).map_err(|_| ConfigError::ConfigErr)?;
+            fs::write(&config_path, contents).map_err(|_| ConfigError::ConfigErr)?;
+            Ok(config)
+        }
+    }
+}
+
+#[derive(Debug, Deserialize, Serialize, Clone)]
 struct LibConfig {
-    component_search_engine_symbols: PathBuf,
-    component_serach_engine_footprints: PathBuf,
+    symacsys_symbols: Option<PathBuf>,
+    symacsys_footprints: Option<PathBuf>,
 }
 
-fn main() -> Result<()> {
-    let (tx, rx) = mpsc::channel::<Result<Event>>();
+enum SourceType {
+    SymacSys,
+    UltraLibrarian,
+}
+
+#[derive(Error, Debug)]
+enum ConfigError {
+    #[error("Config error")]
+    ConfigErr,
+}
+
+#[derive(Error, Debug)]
+enum SourceError {
+    #[error("Unknown Source")]
+    SourceUnknown,
+    #[error("Filename Error")]
+    FilenameError,
+}
+
+fn main() -> notify::Result<()> {
+    let config = Config::load_or_create().unwrap();
+    if config.libraries.is_some() {
+        if config.libraries.clone().unwrap().symacsys_symbols.is_some() {
+            println!("{:?}", config.libraries.unwrap().symacsys_symbols.unwrap());
+        }
+    }
+    let (tx, rx) = mpsc::channel::<notify::Result<Event>>();
     let mut watcher = notify::recommended_watcher(tx)?;
     let downloads = PathBuf::from(env::var("HOME").unwrap()).join("Downloads");
-    watcher.watch(&downloads, RecursiveMode::Recursive)?;
+    watcher.watch(&downloads, RecursiveMode::NonRecursive)?;
 
     for res in rx {
         match res {
-            Ok(event) => println!("event: {:?}", event.paths[0]),
+            Ok(event) => {
+                if event.kind != EventKind::Create(CreateKind::File) {
+                    continue;
+                }
+                if !validate_zip(&event.paths[0]) {
+                    continue;
+                }
+
+                let Ok(source_type) = find_source_type(&event.paths[0]) else {
+                    continue;
+                };
+
+                match source_type {
+                    SourceType::SymacSys => println!("SymacSys detected"),
+                    SourceType::UltraLibrarian => println!("UltraLibrarian detected"),
+                }
+            }
             Err(e) => println!("watch error: {:?}", e),
         }
     }
@@ -36,9 +96,27 @@ fn main() -> Result<()> {
     Ok(())
 }
 
-fn validate_lib(path: PathBuf) -> bool {
-    if path.is_file() {
-        let filename = path.file_name();
-    }
-    return false;
+fn validate_zip(path: &Path) -> bool {
+    path.is_file()
+        && path
+            .extension()
+            .and_then(|e| e.to_str())
+            .map(|e| e.eq_ignore_ascii_case("zip"))
+            .unwrap_or(false)
+}
+
+fn find_source_type(path: &Path) -> Result<SourceType, SourceError> {
+    let name = path
+        .file_name()
+        .ok_or(SourceError::FilenameError)?
+        .to_str()
+        .ok_or(SourceError::FilenameError)?;
+
+    if name.starts_with("LIB_") {
+        Ok(SourceType::SymacSys)
+    } else if name.starts_with("ul_") {
+        Ok(SourceType::UltraLibrarian)
+    } else {
+        Err(SourceError::SourceUnknown)
+    }
 }