diff --git a/src/main.rs b/src/main.rs
index e9587c4..432ebc1 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,24 +1,3 @@
-fn backup_file_path(file_path: &std::path::Path) -> Result<std::path::PathBuf, ask_dracula::Error>
-{
-	let file_name = file_path.file_name()
-		.ok_or(ask_dracula::Error::new_not_a_file(file_path.to_owned()))?;
-
-	let mut i = 0;
-
-	loop
-	{
-		i += 1;
-
-		let backup_file_name = format!("{}.{}~", file_name.to_string_lossy(), i);
-		let backup_file_path = file_path.with_file_name(backup_file_name);
-
-		if !backup_file_path.exists()
-		{
-			return Ok(backup_file_path);
-		}
-	}
-}
-
 fn find_conjecture<'a>(project: &'a ask_dracula::Project,
 	proof_direction: ask_dracula::project::ProofDirection)
 	-> Option<&'a ask_dracula::project::Statement>
@@ -145,8 +124,6 @@ fn main() -> Result<(), Box<dyn std::error::Error>>
 	let (_, mut project) = ask_dracula::parse::project(&file_content)
 		.map_err(|_| "couldn’t parse input file")?;
 
-	let replace_statement_kind_regex = regex::Regex::new(r"(assertion)").unwrap();
-
 	let proof_directions = match matches.value_of("proof-direction").unwrap()
 	{
 		"forward" => vec![ask_dracula::project::ProofDirection::Forward],
@@ -200,17 +177,6 @@ fn main() -> Result<(), Box<dyn std::error::Error>>
 
 					conjecture.kind = ask_dracula::project::StatementKind::Axiom;
 					conjecture.original_text = replace_statement_kind_regex.replace(&conjecture.original_text, "axiom").to_string();
-
-					let backup_file_path = backup_file_path(file_path)?;
-
-					// Make backup of old file
-					std::fs::rename(file_path, backup_file_path)
-						.map_err(|error| ask_dracula::Error::new_write_file(file_path.to_owned(), error))?;
-
-					// Write updated version of the file
-					let file_content = format!("{}", project);
-					std::fs::write(file_path, &file_content)
-						.map_err(|error| ask_dracula::Error::new_write_file(file_path.to_owned(), error))?;
 				},
 				ProofResult::Satisfiable =>
 				{