diff --git a/actix-settings/CHANGES.md b/actix-settings/CHANGES.md
index 25e45859d..2fb8293f3 100644
--- a/actix-settings/CHANGES.md
+++ b/actix-settings/CHANGES.md
@@ -2,11 +2,15 @@
 
 ## Unreleased - 2022-xx-xx
 
+- Rename `AtError => Error`.
+- Remove `AtResult` type alias.
 
 ## 0.6.0 - 2022-07-31
+
 - Update Actix Web dependencies to v4 ecosystem.
 - Rename `actix.ssl` settings object to `actix.tls`.
 - `NoSettings` is now marked `#[non_exhaustive]`.
 
 ## 0.5.2 - 2022-07-31
+
 - Adopted into @actix org from <https://github.com/jjpe/actix-settings>.
diff --git a/actix-settings/src/error.rs b/actix-settings/src/error.rs
index 009962b18..f3834cf45 100644
--- a/actix-settings/src/error.rs
+++ b/actix-settings/src/error.rs
@@ -2,12 +2,9 @@ use std::{env::VarError, io, num::ParseIntError, path::PathBuf, str::ParseBoolEr
 
 use toml::de::Error as TomlError;
 
-/// Convenience type alias for `Result<T, AtError>`.
-pub type AtResult<T> = std::result::Result<T, AtError>;
-
 /// Errors that can be returned from methods in this crate.
 #[derive(Debug, Clone)]
-pub enum AtError {
+pub enum Error {
     /// Environment variable does not exists or is invalid.
     EnvVarError(VarError),
 
@@ -42,7 +39,7 @@ pub enum AtError {
 
 macro_rules! InvalidValue {
     (expected: $expected:expr, got: $got:expr,) => {
-        crate::AtError::InvalidValue {
+        crate::Error::InvalidValue {
             expected: $expected,
             got: $got.to_string(),
             file: file!(),
@@ -52,56 +49,56 @@ macro_rules! InvalidValue {
     };
 }
 
-impl From<io::Error> for AtError {
+impl From<io::Error> for Error {
     fn from(err: io::Error) -> Self {
         Self::IoError(ioe::IoError::from(err))
     }
 }
 
-impl From<ioe::IoError> for AtError {
+impl From<ioe::IoError> for Error {
     fn from(err: ioe::IoError) -> Self {
         Self::IoError(err)
     }
 }
 
-impl From<ParseBoolError> for AtError {
+impl From<ParseBoolError> for Error {
     fn from(err: ParseBoolError) -> Self {
         Self::ParseBoolError(err)
     }
 }
 
-impl From<ParseIntError> for AtError {
+impl From<ParseIntError> for Error {
     fn from(err: ParseIntError) -> Self {
         Self::ParseIntError(err)
     }
 }
 
-impl From<TomlError> for AtError {
+impl From<TomlError> for Error {
     fn from(err: TomlError) -> Self {
         Self::TomlError(err)
     }
 }
 
-impl From<VarError> for AtError {
+impl From<VarError> for Error {
     fn from(err: VarError) -> Self {
         Self::EnvVarError(err)
     }
 }
 
-impl From<AtError> for io::Error {
-    fn from(err: AtError) -> Self {
+impl From<Error> for io::Error {
+    fn from(err: Error) -> Self {
         match err {
-            AtError::EnvVarError(var_error) => {
+            Error::EnvVarError(var_error) => {
                 let msg = format!("Env var error: {}", var_error);
                 io::Error::new(io::ErrorKind::InvalidInput, msg)
             }
 
-            AtError::FileExists(path_buf) => {
+            Error::FileExists(path_buf) => {
                 let msg = format!("File exists: {}", path_buf.display());
                 io::Error::new(io::ErrorKind::AlreadyExists, msg)
             }
 
-            AtError::InvalidValue {
+            Error::InvalidValue {
                 expected,
                 ref got,
                 file,
@@ -115,24 +112,24 @@ impl From<AtError> for io::Error {
                 io::Error::new(io::ErrorKind::InvalidInput, msg)
             }
 
-            AtError::IoError(io_error) => io_error.into(),
+            Error::IoError(io_error) => io_error.into(),
 
-            AtError::ParseBoolError(parse_bool_error) => {
+            Error::ParseBoolError(parse_bool_error) => {
                 let msg = format!("Failed to parse boolean: {}", parse_bool_error);
                 io::Error::new(io::ErrorKind::InvalidInput, msg)
             }
 
-            AtError::ParseIntError(parse_int_error) => {
+            Error::ParseIntError(parse_int_error) => {
                 let msg = format!("Failed to parse integer: {}", parse_int_error);
                 io::Error::new(io::ErrorKind::InvalidInput, msg)
             }
 
-            AtError::ParseAddressError(string) => {
+            Error::ParseAddressError(string) => {
                 let msg = format!("Failed to parse address: {}", string);
                 io::Error::new(io::ErrorKind::InvalidInput, msg)
             }
 
-            AtError::TomlError(toml_error) => {
+            Error::TomlError(toml_error) => {
                 let msg = format!("TOML error: {}", toml_error);
                 io::Error::new(io::ErrorKind::InvalidInput, msg)
             }
diff --git a/actix-settings/src/lib.rs b/actix-settings/src/lib.rs
index 857200c84..ed8b4bc84 100644
--- a/actix-settings/src/lib.rs
+++ b/actix-settings/src/lib.rs
@@ -89,13 +89,16 @@ mod error;
 mod parse;
 mod settings;
 
-pub use self::error::{AtError, AtResult};
+pub use self::error::Error;
 pub use self::parse::Parse;
 pub use self::settings::{
     ActixSettings, Address, Backlog, KeepAlive, MaxConnectionRate, MaxConnections, Mode,
     NumWorkers, Timeout, Tls,
 };
 
+/// Convenience type alias for `Result<T, AtError>`.
+type AsResult<T> = std::result::Result<T, Error>;
+
 /// Wrapper for server and application-specific settings.
 #[derive(Debug, Clone, PartialEq, Eq, Hash, Deserialize)]
 #[serde(bound = "A: Deserialize<'de>")]
@@ -129,7 +132,7 @@ where
     ///
     /// If the file doesn't exist, it is generated from the default TOML template, after which the
     /// newly generated file is read in and parsed.
-    pub fn parse_toml<P>(filepath: P) -> AtResult<Self>
+    pub fn parse_toml<P>(filepath: P) -> AsResult<Self>
     where
         P: AsRef<Path>,
     {
@@ -140,8 +143,9 @@ where
         }
 
         let mut f = File::open(filepath)?;
-        // TODO: don't bail on metadata fail
-        let mut contents = String::with_capacity(f.metadata()?.len() as usize);
+        let len_guess = f.metadata().map(|md| md.len()).unwrap_or(128);
+
+        let mut contents = String::with_capacity(len_guess as usize);
         f.read_to_string(&mut contents)?;
 
         Ok(toml::from_str::<Self>(&contents)?)
@@ -150,13 +154,13 @@ where
     /// Parse an instance of `Self` straight from the default TOML template.
     // TODO: make infallible
     // TODO: consider "template" rename
-    pub fn from_default_template() -> AtResult<Self> {
+    pub fn from_default_template() -> AsResult<Self> {
         Self::from_template(Self::DEFAULT_TOML_TEMPLATE)
     }
 
     /// Parse an instance of `Self` straight from the default TOML template.
     // TODO: consider "template" rename
-    pub fn from_template(template: &str) -> AtResult<Self> {
+    pub fn from_template(template: &str) -> AsResult<Self> {
         Ok(toml::from_str(template)?)
     }
 
@@ -165,14 +169,14 @@ where
     /// # Errors
     /// Returns a [`FileExists`](crate::AtError::FileExists) error if a file already exists at that
     /// location.
-    pub fn write_toml_file<P>(filepath: P) -> AtResult<()>
+    pub fn write_toml_file<P>(filepath: P) -> AsResult<()>
     where
         P: AsRef<Path>,
     {
         let filepath = filepath.as_ref();
 
         if filepath.exists() {
-            return Err(AtError::FileExists(filepath.to_path_buf()));
+            return Err(Error::FileExists(filepath.to_path_buf()));
         }
 
         let mut file = File::create(filepath)?;
@@ -188,7 +192,7 @@ where
     /// ```
     /// use actix_settings::{Settings, Mode};
     ///
-    /// # fn inner() -> actix_settings::AtResult<()> {
+    /// # fn inner() -> Result<(), actix_settings::Error> {
     /// let mut settings = Settings::from_default_template()?;
     /// assert_eq!(settings.actix.mode, Mode::Development);
     ///
@@ -196,7 +200,7 @@ where
     /// assert_eq!(settings.actix.mode, Mode::Production);
     /// # Ok(()) }
     /// ```
-    pub fn override_field<F, V>(field: &mut F, value: V) -> AtResult<()>
+    pub fn override_field<F, V>(field: &mut F, value: V) -> AsResult<()>
     where
         F: Parse,
         V: AsRef<str>,
@@ -213,7 +217,7 @@ where
     ///
     /// std::env::set_var("OVERRIDE__MODE", "production");
     ///
-    /// # fn inner() -> actix_settings::AtResult<()> {
+    /// # fn inner() -> Result<(), actix_settings::Error> {
     /// let mut settings = Settings::from_default_template()?;
     /// assert_eq!(settings.actix.mode, Mode::Development);
     ///
@@ -221,14 +225,14 @@ where
     /// assert_eq!(settings.actix.mode, Mode::Production);
     /// # Ok(()) }
     /// ```
-    pub fn override_field_with_env_var<F, N>(field: &mut F, var_name: N) -> AtResult<()>
+    pub fn override_field_with_env_var<F, N>(field: &mut F, var_name: N) -> AsResult<()>
     where
         F: Parse,
         N: AsRef<str>,
     {
         match env::var(var_name.as_ref()) {
             Err(env::VarError::NotPresent) => Ok((/*NOP*/)),
-            Err(var_error) => Err(AtError::from(var_error)),
+            Err(var_error) => Err(Error::from(var_error)),
             Ok(value) => Self::override_field(field, value),
         }
     }
diff --git a/actix-settings/src/parse.rs b/actix-settings/src/parse.rs
index 9a6c7f59c..e88a64a3c 100644
--- a/actix-settings/src/parse.rs
+++ b/actix-settings/src/parse.rs
@@ -1,16 +1,16 @@
 use std::{path::PathBuf, str::FromStr};
 
-use crate::AtError;
+use crate::Error;
 
 /// A specialized `FromStr` trait that returns [`AtError`] errors
 pub trait Parse: Sized {
     /// Parse `Self` from `string`.
-    fn parse(string: &str) -> Result<Self, AtError>;
+    fn parse(string: &str) -> Result<Self, Error>;
 }
 
 impl Parse for bool {
-    fn parse(string: &str) -> Result<Self, AtError> {
-        Self::from_str(string).map_err(AtError::from)
+    fn parse(string: &str) -> Result<Self, Error> {
+        Self::from_str(string).map_err(Error::from)
     }
 }
 
@@ -18,8 +18,8 @@ macro_rules! impl_parse_for_int_type {
     ($($int_type:ty),+ $(,)?) => {
         $(
             impl Parse for $int_type {
-                fn parse(string: &str) -> Result<Self, AtError> {
-                    Self::from_str(string).map_err(AtError::from)
+                fn parse(string: &str) -> Result<Self, Error> {
+                    Self::from_str(string).map_err(Error::from)
                 }
             }
         )+
@@ -28,13 +28,13 @@ macro_rules! impl_parse_for_int_type {
 impl_parse_for_int_type![i8, i16, i32, i64, i128, u8, u16, u32, u64, u128];
 
 impl Parse for String {
-    fn parse(string: &str) -> Result<Self, AtError> {
+    fn parse(string: &str) -> Result<Self, Error> {
         Ok(string.to_string())
     }
 }
 
 impl Parse for PathBuf {
-    fn parse(string: &str) -> Result<Self, AtError> {
+    fn parse(string: &str) -> Result<Self, Error> {
         Ok(PathBuf::from(string))
     }
 }
diff --git a/actix-settings/src/settings/address.rs b/actix-settings/src/settings/address.rs
index c07fff1b6..5f541cac2 100644
--- a/actix-settings/src/settings/address.rs
+++ b/actix-settings/src/settings/address.rs
@@ -2,7 +2,7 @@ use once_cell::sync::Lazy;
 use regex::Regex;
 use serde::Deserialize;
 
-use crate::{AtError, Parse};
+use crate::{Error, Parse};
 
 static ADDR_REGEX: Lazy<Regex> = Lazy::new(|| {
     Regex::new(
@@ -48,14 +48,14 @@ pub struct Address {
 }
 
 impl Parse for Address {
-    fn parse(string: &str) -> Result<Self, AtError> {
+    fn parse(string: &str) -> Result<Self, Error> {
         let mut items = string
             .trim()
             .trim_start_matches('[')
             .trim_end_matches(']')
             .split(',');
 
-        let parse_error = || AtError::ParseAddressError(string.to_string());
+        let parse_error = || Error::ParseAddressError(string.to_string());
 
         if !ADDR_REGEX.is_match(string) {
             return Err(parse_error());
@@ -69,8 +69,8 @@ impl Parse for Address {
 }
 
 impl Parse for Vec<Address> {
-    fn parse(string: &str) -> Result<Self, AtError> {
-        let parse_error = || AtError::ParseAddressError(string.to_string());
+    fn parse(string: &str) -> Result<Self, Error> {
+        let parse_error = || Error::ParseAddressError(string.to_string());
 
         if !ADDR_LIST_REGEX.is_match(string) {
             return Err(parse_error());
diff --git a/actix-settings/src/settings/backlog.rs b/actix-settings/src/settings/backlog.rs
index 500c20f13..668183d9d 100644
--- a/actix-settings/src/settings/backlog.rs
+++ b/actix-settings/src/settings/backlog.rs
@@ -2,7 +2,7 @@ use std::fmt;
 
 use serde::de;
 
-use crate::{AtError, AtResult, Parse};
+use crate::{AsResult, Error, Parse};
 
 /// The maximum number of pending connections.
 ///
@@ -22,7 +22,7 @@ pub enum Backlog {
 }
 
 impl Parse for Backlog {
-    fn parse(string: &str) -> AtResult<Self> {
+    fn parse(string: &str) -> AsResult<Self> {
         match string {
             "default" => Ok(Backlog::Default),
             string => match string.parse::<usize>() {
@@ -57,7 +57,7 @@ impl<'de> de::Deserialize<'de> for Backlog {
             {
                 match Backlog::parse(value) {
                     Ok(backlog) => Ok(backlog),
-                    Err(AtError::InvalidValue { expected, got, .. }) => Err(
+                    Err(Error::InvalidValue { expected, got, .. }) => Err(
                         de::Error::invalid_value(de::Unexpected::Str(&got), &expected),
                     ),
                     Err(_) => unreachable!(),
diff --git a/actix-settings/src/settings/keep_alive.rs b/actix-settings/src/settings/keep_alive.rs
index 96e1ed476..1395984ab 100644
--- a/actix-settings/src/settings/keep_alive.rs
+++ b/actix-settings/src/settings/keep_alive.rs
@@ -4,7 +4,7 @@ use once_cell::sync::Lazy;
 use regex::Regex;
 use serde::de;
 
-use crate::{AtError, AtResult, Parse};
+use crate::{AsResult, Error, Parse};
 
 /// The server keep-alive preference.
 ///
@@ -28,7 +28,7 @@ pub enum KeepAlive {
 }
 
 impl Parse for KeepAlive {
-    fn parse(string: &str) -> AtResult<Self> {
+    fn parse(string: &str) -> AsResult<Self> {
         pub(crate) static FMT: Lazy<Regex> =
             Lazy::new(|| Regex::new(r"^\d+ seconds$").expect("Failed to compile regex: FMT"));
 
@@ -82,7 +82,7 @@ impl<'de> de::Deserialize<'de> for KeepAlive {
             {
                 match KeepAlive::parse(value) {
                     Ok(keep_alive) => Ok(keep_alive),
-                    Err(AtError::InvalidValue { expected, got, .. }) => Err(
+                    Err(Error::InvalidValue { expected, got, .. }) => Err(
                         de::Error::invalid_value(de::Unexpected::Str(&got), &expected),
                     ),
                     Err(_) => unreachable!(),
diff --git a/actix-settings/src/settings/max_connection_rate.rs b/actix-settings/src/settings/max_connection_rate.rs
index d6706783a..702f093b5 100644
--- a/actix-settings/src/settings/max_connection_rate.rs
+++ b/actix-settings/src/settings/max_connection_rate.rs
@@ -2,7 +2,7 @@ use std::fmt;
 
 use serde::de;
 
-use crate::{AtError, AtResult, Parse};
+use crate::{AsResult, Error, Parse};
 
 /// The maximum per-worker concurrent TLS connection limit.
 ///
@@ -19,7 +19,7 @@ pub enum MaxConnectionRate {
 }
 
 impl Parse for MaxConnectionRate {
-    fn parse(string: &str) -> AtResult<Self> {
+    fn parse(string: &str) -> AsResult<Self> {
         match string {
             "default" => Ok(MaxConnectionRate::Default),
             string => match string.parse::<usize>() {
@@ -54,7 +54,7 @@ impl<'de> de::Deserialize<'de> for MaxConnectionRate {
             {
                 match MaxConnectionRate::parse(value) {
                     Ok(max_connection_rate) => Ok(max_connection_rate),
-                    Err(AtError::InvalidValue { expected, got, .. }) => Err(
+                    Err(Error::InvalidValue { expected, got, .. }) => Err(
                         de::Error::invalid_value(de::Unexpected::Str(&got), &expected),
                     ),
                     Err(_) => unreachable!(),
diff --git a/actix-settings/src/settings/max_connections.rs b/actix-settings/src/settings/max_connections.rs
index f0ffdcdf3..1bb3dd04e 100644
--- a/actix-settings/src/settings/max_connections.rs
+++ b/actix-settings/src/settings/max_connections.rs
@@ -2,7 +2,7 @@ use std::fmt;
 
 use serde::de;
 
-use crate::{AtError, AtResult, Parse};
+use crate::{AsResult, Error, Parse};
 
 /// The maximum per-worker number of concurrent connections.
 ///
@@ -19,7 +19,7 @@ pub enum MaxConnections {
 }
 
 impl Parse for MaxConnections {
-    fn parse(string: &str) -> AtResult<Self> {
+    fn parse(string: &str) -> AsResult<Self> {
         match string {
             "default" => Ok(MaxConnections::Default),
             string => match string.parse::<usize>() {
@@ -54,7 +54,7 @@ impl<'de> de::Deserialize<'de> for MaxConnections {
             {
                 match MaxConnections::parse(value) {
                     Ok(max_connections) => Ok(max_connections),
-                    Err(AtError::InvalidValue { expected, got, .. }) => Err(
+                    Err(Error::InvalidValue { expected, got, .. }) => Err(
                         de::Error::invalid_value(de::Unexpected::Str(&got), &expected),
                     ),
                     Err(_) => unreachable!(),
diff --git a/actix-settings/src/settings/mode.rs b/actix-settings/src/settings/mode.rs
index 3833da38a..6eb1ef587 100644
--- a/actix-settings/src/settings/mode.rs
+++ b/actix-settings/src/settings/mode.rs
@@ -1,6 +1,6 @@
 use serde::Deserialize;
 
-use crate::{AtResult, Parse};
+use crate::{AsResult, Parse};
 
 /// Marker of intended deployment environment.
 #[derive(Debug, Clone, PartialEq, Eq, Hash, Deserialize)]
@@ -14,7 +14,7 @@ pub enum Mode {
 }
 
 impl Parse for Mode {
-    fn parse(string: &str) -> AtResult<Self> {
+    fn parse(string: &str) -> AsResult<Self> {
         match string {
             "development" => Ok(Self::Development),
             "production" => Ok(Self::Production),
diff --git a/actix-settings/src/settings/num_workers.rs b/actix-settings/src/settings/num_workers.rs
index ff8d00b8b..39c1bc32b 100644
--- a/actix-settings/src/settings/num_workers.rs
+++ b/actix-settings/src/settings/num_workers.rs
@@ -2,7 +2,7 @@ use std::fmt;
 
 use serde::de;
 
-use crate::{AtError, AtResult, Parse};
+use crate::{AsResult, Error, Parse};
 
 /// The number of workers that the server should start.
 ///
@@ -18,7 +18,7 @@ pub enum NumWorkers {
 }
 
 impl Parse for NumWorkers {
-    fn parse(string: &str) -> AtResult<Self> {
+    fn parse(string: &str) -> AsResult<Self> {
         match string {
             "default" => Ok(NumWorkers::Default),
             string => match string.parse::<usize>() {
@@ -53,7 +53,7 @@ impl<'de> de::Deserialize<'de> for NumWorkers {
             {
                 match NumWorkers::parse(value) {
                     Ok(num_workers) => Ok(num_workers),
-                    Err(AtError::InvalidValue { expected, got, .. }) => Err(
+                    Err(Error::InvalidValue { expected, got, .. }) => Err(
                         de::Error::invalid_value(de::Unexpected::Str(&got), &expected),
                     ),
                     Err(_) => unreachable!(),
diff --git a/actix-settings/src/settings/timeout.rs b/actix-settings/src/settings/timeout.rs
index 1bed71396..dff3899d5 100644
--- a/actix-settings/src/settings/timeout.rs
+++ b/actix-settings/src/settings/timeout.rs
@@ -4,7 +4,7 @@ use once_cell::sync::Lazy;
 use regex::Regex;
 use serde::de;
 
-use crate::{AtError, AtResult, Parse};
+use crate::{AsResult, Error, Parse};
 
 /// A timeout duration in milliseconds or seconds.
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -20,7 +20,7 @@ pub enum Timeout {
 }
 
 impl Parse for Timeout {
-    fn parse(string: &str) -> AtResult<Self> {
+    fn parse(string: &str) -> AsResult<Self> {
         pub static FMT: Lazy<Regex> = Lazy::new(|| {
             Regex::new(r"^\d+ (milliseconds|seconds)$").expect("Failed to compile regex: FMT")
         });
@@ -85,7 +85,7 @@ impl<'de> de::Deserialize<'de> for Timeout {
             {
                 match Timeout::parse(value) {
                     Ok(num_workers) => Ok(num_workers),
-                    Err(AtError::InvalidValue { expected, got, .. }) => Err(
+                    Err(Error::InvalidValue { expected, got, .. }) => Err(
                         de::Error::invalid_value(de::Unexpected::Str(&got), &expected),
                     ),
                     Err(_) => unreachable!(),