diff --git a/Cargo.toml b/Cargo.toml
index 9b5cecc..3a52ace 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,8 +8,11 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
-default = ["parallel"]
+default = ["parallel", "limit-concurrency", "splash"]
 
+# Limit the concurrent operations of parallel mode to 4096
+limit-concurrency = ["parallel"]
+splash = []
 parallel = ["tokio", "futures"]
 threads = ["parallel", "tokio/rt-threaded"]
 
diff --git a/src/arg.rs b/src/arg.rs
new file mode 100644
index 0000000..b60d2c5
--- /dev/null
+++ b/src/arg.rs
@@ -0,0 +1,18 @@
+//! Argument stuff
+use super::*;
+
+
+/// Name of executable
+pub fn program_name() -> &'static str
+{
+    lazy_static! {
+	static ref NAME: String = std::env::args().next().unwrap();
+    }
+    &NAME[..]
+}
+
+/// Print usage
+pub fn usage()
+{
+    println!(r#"Usage: {} <files...>"#, program_name());
+}
diff --git a/src/ext.rs b/src/ext.rs
new file mode 100644
index 0000000..56aba06
--- /dev/null
+++ b/src/ext.rs
@@ -0,0 +1,25 @@
+use super::*;
+use std::iter;
+
+pub trait StringJoinExt: Sized
+{
+    fn join<P: AsRef<str>>(self, sep: P) -> String;
+}
+
+impl<I,T> StringJoinExt for I
+where I: IntoIterator<Item=T>,
+      T: AsRef<str>
+{
+    fn join<P: AsRef<str>>(self, sep: P) -> String
+    {
+	let mut string = String::new();
+	for (first, s) in iter::successors(Some(true), |_| Some(false)).zip(self.into_iter())
+	{
+	    if !first {
+		string.push_str(sep.as_ref());
+	    }
+	    string.push_str(s.as_ref());
+	}
+	string
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index ccfc34a..bc242ff 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -8,27 +8,58 @@ use color_eyre::{
     Help, SectionExt,
 };
 use lazy_static::lazy_static;
+use cfg_if::cfg_if;
 
 fn init() -> eyre::Result<()>
 {
     color_eyre::install()?;
-    pretty_env_logger::init(); //TODO: Change to builder
+    if let None = std::env::var_os("RUST_LOG") {
+	std::env::set_var("RUST_LOG", "info");
+    }
+    pretty_env_logger::init();
     trace!("Initialised");
     Ok(())
 }
 
+mod ext;
+use ext::*;
+mod map;
+use map::*;
 mod temp;
 mod error;
+mod arg;
+
+cfg_if!{
+    if #[cfg(feature="splash")] {
+	mod splash;
+    } else {
+	mod splash {
+	    #[inline(always)] pub fn splash() -> ! {
+		super::arg::usage();
+		std::process::exit(1)
+	    }
+	}
+    }
+}
 
 #[cfg(feature="parallel")]
 mod parallel;
 
+fn args_or_out<T: ExactSizeIterator>(i: T, low: usize) -> T
+{
+    if i.len() < low {
+	splash::splash();
+    } else {
+	i
+    }
+}
+
 #[cfg(feature="parallel")]
 #[cfg_attr(feature="parallel", tokio::main)]
 async fn main() -> eyre::Result<()> {
     reyre!(init(), "Failed to initialise")?;
     
-    reyre!(parallel::main(std::env::args().skip(1)).await, "Jobs failed")
+    reyre!(parallel::main(args_or_out(std::env::args(), 2).skip(1).dedup()).await, "Jobs failed")
 }
 
 #[cfg(not(feature="parallel"))]
@@ -37,5 +68,6 @@ mod serial;
 #[cfg(not(feature="parallel"))]
 fn main() -> eyre::Result<()> {
     reyre!(init(), "Failed to initialise")?;
+    let args = args_or_out(std::env::args(), 2).skip(1).dedup();
     todo!("Sync unimplemented")
 }
diff --git a/src/map.rs b/src/map.rs
new file mode 100644
index 0000000..1dc5b3c
--- /dev/null
+++ b/src/map.rs
@@ -0,0 +1,66 @@
+//! Map iter
+use super::*;
+use std::{
+    iter,
+    collections::HashSet,
+    hash::Hash,
+};
+
+//TODO: Feature flag for SHA256 hashing
+type HashOutput = u64;
+
+fn compute<H: Hash>(what: &H) -> HashOutput
+{
+    use std::hash::Hasher;
+    let mut hasher = std::collections::hash_map::DefaultHasher::new();
+    what.hash(&mut hasher);
+    hasher.finish()
+}
+
+pub struct DedupIter<I: Iterator>(I, HashSet<HashOutput>)
+where <I as Iterator>::Item: Hash;
+
+impl<I: Iterator> Iterator for DedupIter<I>
+where I::Item: Hash
+{
+    type Item = I::Item;
+    fn next(&mut self) -> Option<Self::Item>
+    {
+	if let Some(next) = self.0.next() {
+	    let hash = compute(&next);
+	    if self.1.insert(hash) {
+		Some(next)
+	    } else {
+		return self.next();
+	    }
+	} else {
+	    None
+	}
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>)
+    {
+	let (low, high) = self.0.size_hint();
+
+	(if low < 1 {0} else {1}, high)
+    }
+}
+
+pub trait DedupIterExt: Iterator + Sized
+where Self::Item: Hash
+{
+    fn dedup(self) -> DedupIter<Self>;
+}
+
+impl<I: Iterator> DedupIterExt for I
+where I::Item: Hash
+{
+    fn dedup(self) -> DedupIter<Self>
+    {
+	let set = match self.size_hint() {
+	    (0, Some(0)) | (0, None) => HashSet::new(),
+	    (x, None) | (_, Some(x)) => HashSet::with_capacity(x),
+	};
+	DedupIter(self, set)
+    }
+}
diff --git a/src/parallel.rs b/src/parallel.rs
index f3e1165..79925f8 100644
--- a/src/parallel.rs
+++ b/src/parallel.rs
@@ -25,7 +25,13 @@ use tokio::{
 };
 use error::{Error, ErrorKind};
 
-const MAX_WORKERS: Option<NonZeroUsize> = Some(unsafe {NonZeroUsize::new_unchecked(4096)});
+cfg_if!{
+    if #[cfg(feature="limit-concurrency")] {
+	pub const MAX_WORKERS: Option<NonZeroUsize> = Some(unsafe {NonZeroUsize::new_unchecked(4096)});
+    } else {
+	pub const MAX_WORKERS: Option<NonZeroUsize> = None;
+    }
+}
 
 fn gensem() -> Option<Arc<Semaphore>>
 {
@@ -67,7 +73,7 @@ async fn work<P: AsRef<Path>>(apath: P, sem: Option<Arc<Semaphore>>) -> Result<(
     use std::os::unix::fs::MetadataExt;
 
     let nlink = meta.nlink();
-    debug!("<{:?}> Links: {}", path, nlink);
+    debug!("<{:?}> has {} links", path, nlink);
     if nlink > 1 {
 	//todo work i guess fuck it
 	unlink(path).await?;
@@ -80,8 +86,13 @@ async fn work<P: AsRef<Path>>(apath: P, sem: Option<Arc<Semaphore>>) -> Result<(
 pub async fn main<I: IntoIterator<Item=String>>(list: I) -> eyre::Result<()>
 {
     let sem = gensem();
-    let mut failures = 0usize;
-    for (i, res) in (0usize..).zip(join_all(list.into_iter().map(|file| tokio::spawn(work(file, sem.clone()))))
+    let list = list.into_iter();
+    let mut failures = match list.size_hint() {
+	(0, Some(0)) | (0, None) => Vec::new(),
+	(x, None) | (_, Some(x)) => Vec::with_capacity(x),
+    };
+    let mut done = 0usize;
+    for (i, res) in (0usize..).zip(join_all(list.map(|file| tokio::spawn(work(file, sem.clone()))))
 				   .map(|x| {trace!("--- {} Finished ---", x.len()); x}).await)
     {
 	//trace!("Done on {:?}", res);
@@ -96,10 +107,11 @@ pub async fn main<I: IntoIterator<Item=String>>(list: I) -> eyre::Result<()>
 			.with_warning(|| "This suggests a bug in the program");
 		} else {
 		    warn!("Child {} cancelled", i);
-		    failures += 1;
+		    return Ok(());
 		}
 	    },
-	    Ok(Err(kind)) if !kind.kind().is_skippable() => { //
+	    Ok(Err(kind)) if !kind.kind().is_skippable() => {
+		failures.push((kind.path().to_owned(), kind.to_string()));
 		let fuck = format!("{:?}", kind.path());
 		let sug = kind.kind().suggestion();
 		let err = Err::<std::convert::Infallible, _>(kind)
@@ -109,18 +121,23 @@ pub async fn main<I: IntoIterator<Item=String>>(list: I) -> eyre::Result<()>
 		    .unwrap_err();
 		error!("{}", err);
 		debug!("Error: {:?}", err);
-		failures += 1;
 	    },
 	    Ok(Err(k)) => {
+		failures.push((k.path().to_owned(), k.to_string()));
 		trace!("<{:?}> Failed (skipped)", k.path());
-		failures+=1;
 	    },
 	}
+	done+=1;
     }
 
-    if failures > 0 {
-	return Err(eyre!("Some tasks failed to complete successfullly"))
-	    .with_section(|| failures.to_string().header("Number of failed tasks"))
+    if failures.len() > 0 {
+	return Err(eyre!("{}/{} tasks failed to complete successfullly", failures.len(), done))
+	    .with_section(|| failures.into_iter()
+			  .map(|(x, err)| format!("{}: {}", x.into_os_string()
+						  .into_string()
+						  .unwrap_or_else(|os| os.to_string_lossy().into_owned()), err))
+			  .join("\n")
+			  .header("Failed tasks:"))
 	    .with_suggestion(|| "Run with `RUST_LOG=debug` or `RUST_LOG=trace` for verbose error reporting");
     }
 
diff --git a/src/splash.rs b/src/splash.rs
new file mode 100644
index 0000000..8f02c91
--- /dev/null
+++ b/src/splash.rs
@@ -0,0 +1,47 @@
+//! Splash screen~
+use super::*;
+use std::borrow::Cow;
+
+macro_rules! feature {
+    (in $name:tt, $desc:literal) => {
+	cfg_if! {
+	    if #[cfg($name)] {
+		println!(" +{}\t{}", stringify!($name), $desc);
+	    }
+	}
+    };
+    ($name:literal, $desc:literal $($tt:tt)*) => {
+	cfg_if! {
+	    if #[cfg(feature=$name)] {
+		println!(" +{}\t{}", $name, format!($desc $($tt)*));
+	    }  else {
+		println!(" -{}", $name);
+	    }
+	}
+    };
+}
+
+pub fn splash() -> ! {
+    arg::usage();
+
+    // splash screen
+    println!(r#"
+> sever ({}) v{}
+>  Coerce hardlinks to new files
+
+For verbose output, set `RUST_LOG` env var to one of the following:
+ trace - Most verbose
+ debug - Verbose
+ info  - Default
+ warn  - Only show warnings
+ error - Only show errors
+
+Made by {} with <3 (Licensed GPL 3.0 or later)"#, arg::program_name(), env!("CARGO_PKG_VERSION"), env!("CARGO_PKG_AUTHORS"));
+    println!("\nEnabled extensions: ");
+    feature!(in nightly, "\tCompiled with Rust nightly extensions");
+    println!();
+    feature!("parallel", "\tWill run up to {} operations in parallel", parallel::MAX_WORKERS.map(|x| Cow::Owned(x.to_string())).unwrap_or(Cow::Borrowed("unlimited")));
+    feature!("limit-concurrency", "Concurrency is capped");
+    feature!("threads", "\tUsing thread-pool");
+    std::process::exit(1)
+}
diff --git a/src/temp.rs b/src/temp.rs
index 40ebe07..9bb25a7 100644
--- a/src/temp.rs
+++ b/src/temp.rs
@@ -54,6 +54,7 @@ impl TempFile
 	d
     }
 
+    #[cfg(feature="parallel")] 
     /// Attempt to remove this temp file async
     pub async fn drop_async(mut self) -> tokio::io::Result<()>
     {
diff --git a/test/hi b/test/hi
new file mode 100644
index 0000000..e69de29