From 0f33b98e75cd6e6aa25be70b26bf930d031216cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Juli=C3=A1n=20Espina?= <jedel0124@gmail.com>
Date: Mon, 5 Feb 2024 06:12:48 +0000
Subject: [PATCH] Simplify Temporal APIs (#3653)

* Simplify Temporal APIs

* cargo fmt

* Unroll deletion of context-free API
---
 .../src/builtins/temporal/calendar/object.rs  | 136 +++---------
 .../src/builtins/temporal/plain_date/mod.rs   |  30 +--
 .../builtins/temporal/plain_date_time/mod.rs  |  26 +--
 .../src/builtins/temporal/time_zone/custom.rs |  22 +-
 core/temporal/src/components/calendar.rs      | 198 +++++++++---------
 core/temporal/src/components/date.rs          | 107 +++-------
 core/temporal/src/components/datetime.rs      |  79 ++++---
 core/temporal/src/components/duration.rs      |   8 +-
 core/temporal/src/components/duration/date.rs |   4 +-
 core/temporal/src/components/tz.rs            |  29 +--
 core/temporal/src/components/zoneddatetime.rs | 104 +++------
 11 files changed, 277 insertions(+), 466 deletions(-)

diff --git a/core/engine/src/builtins/temporal/calendar/object.rs b/core/engine/src/builtins/temporal/calendar/object.rs
index 64e0ef3d99..04ab9aa3f7 100644
--- a/core/engine/src/builtins/temporal/calendar/object.rs
+++ b/core/engine/src/builtins/temporal/calendar/object.rs
@@ -12,12 +12,11 @@ use crate::{
     property::PropertyKey,
     Context, JsObject, JsString, JsValue,
 };
-use std::any::Any;
 
 use boa_macros::utf16;
 use boa_temporal::{
     components::{
-        calendar::{CalendarDateLike, CalendarProtocol, DateTypes},
+        calendar::{CalendarDateLike, CalendarProtocol},
         Date, Duration, MonthDay, YearMonth,
     },
     options::ArithmeticOverflow,
@@ -29,29 +28,18 @@ use plain_date_time::PlainDateTime;
 use plain_month_day::PlainMonthDay;
 use plain_year_month::PlainYearMonth;
 
-/// The custom data types for a Custom `JsObject` Calendar.
-#[derive(Debug, Clone, Copy)]
-pub struct CustomDateLikes;
-
-impl DateTypes<JsObject> for CustomDateLikes {
+impl CalendarProtocol for JsObject {
     type Date = JsObject<PlainDate>;
     type DateTime = JsObject<PlainDateTime>;
     type YearMonth = JsObject<PlainYearMonth>;
     type MonthDay = JsObject<PlainMonthDay>;
-}
-
-impl CalendarProtocol for JsObject {
-    type DateLikes = CustomDateLikes;
+    type Context = Context;
     fn date_from_fields(
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<Date<Self>> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let method = self
             .get(utf16!("dateFromFields"), context)
             .expect("method must exist on a object that implements the CalendarProtocol.");
@@ -97,12 +85,8 @@ impl CalendarProtocol for JsObject {
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<YearMonth<JsObject>> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let method = self
             .get(utf16!("yearMonthFromFields"), context)
             .expect("method must exist on a object that implements the CalendarProtocol.");
@@ -150,12 +134,8 @@ impl CalendarProtocol for JsObject {
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<MonthDay<JsObject>> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let method = self
             .get(utf16!("yearMonthFromFields"), context)
             .expect("method must exist on a object that implements the CalendarProtocol.");
@@ -204,7 +184,7 @@ impl CalendarProtocol for JsObject {
         _date: &Date<JsObject>,
         _duration: &Duration,
         _overflow: ArithmeticOverflow,
-        _context: &mut dyn Any,
+        _context: &mut Context,
     ) -> TemporalResult<Date<JsObject>> {
         // TODO
         Err(TemporalError::general("Not yet implemented."))
@@ -215,7 +195,7 @@ impl CalendarProtocol for JsObject {
         _one: &Date<JsObject>,
         _two: &Date<JsObject>,
         _largest_unit: boa_temporal::options::TemporalUnit,
-        _context: &mut dyn Any,
+        _context: &mut Context,
     ) -> TemporalResult<Duration> {
         // TODO
         Err(TemporalError::general("Not yet implemented."))
@@ -224,7 +204,7 @@ impl CalendarProtocol for JsObject {
     fn era(
         &self,
         _: &CalendarDateLike<JsObject>,
-        _: &mut dyn Any,
+        _: &mut Context,
     ) -> TemporalResult<Option<TinyAsciiStr<16>>> {
         // Return undefined as custom calendars do not implement -> Currently.
         Ok(None)
@@ -233,7 +213,7 @@ impl CalendarProtocol for JsObject {
     fn era_year(
         &self,
         _: &CalendarDateLike<JsObject>,
-        _: &mut dyn Any,
+        _: &mut Context,
     ) -> TemporalResult<Option<i32>> {
         // Return undefined as custom calendars do not implement -> Currently.
         Ok(None)
@@ -242,12 +222,8 @@ impl CalendarProtocol for JsObject {
     fn year(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<i32> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -288,12 +264,8 @@ impl CalendarProtocol for JsObject {
     fn month(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u8> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -334,12 +306,8 @@ impl CalendarProtocol for JsObject {
     fn month_code(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<TinyAsciiStr<4>> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -365,12 +333,8 @@ impl CalendarProtocol for JsObject {
     fn day(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u8> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -411,12 +375,8 @@ impl CalendarProtocol for JsObject {
     fn day_of_week(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u16> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -459,12 +419,8 @@ impl CalendarProtocol for JsObject {
     fn day_of_year(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u16> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -507,12 +463,8 @@ impl CalendarProtocol for JsObject {
     fn week_of_year(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u16> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -555,12 +507,8 @@ impl CalendarProtocol for JsObject {
     fn year_of_week(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<i32> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -596,12 +544,8 @@ impl CalendarProtocol for JsObject {
     fn days_in_week(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u16> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -644,12 +588,8 @@ impl CalendarProtocol for JsObject {
     fn days_in_month(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u16> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -693,12 +633,8 @@ impl CalendarProtocol for JsObject {
     fn days_in_year(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u16> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -741,12 +677,8 @@ impl CalendarProtocol for JsObject {
     fn months_in_year(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<u16> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -791,12 +723,8 @@ impl CalendarProtocol for JsObject {
     fn in_leap_year(
         &self,
         date_like: &CalendarDateLike<JsObject>,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<bool> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let date_like = date_like_to_object(date_like, context)?;
 
         let method = self
@@ -818,11 +746,7 @@ impl CalendarProtocol for JsObject {
         Ok(result)
     }
 
-    fn fields(&self, fields: Vec<String>, context: &mut dyn Any) -> TemporalResult<Vec<String>> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
+    fn fields(&self, fields: Vec<String>, context: &mut Context) -> TemporalResult<Vec<String>> {
         let fields_js = Array::create_array_from_list(
             fields.iter().map(|s| JsString::from(s.clone()).into()),
             context,
@@ -867,12 +791,8 @@ impl CalendarProtocol for JsObject {
         &self,
         fields: &TemporalFields,
         additional_fields: &TemporalFields,
-        context: &mut dyn Any,
+        context: &mut Context,
     ) -> TemporalResult<TemporalFields> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
         let fields = JsObject::from_temporal_fields(fields, context)
             .map_err(|e| TemporalError::general(e.to_string()))?;
         let add_fields = JsObject::from_temporal_fields(additional_fields, context)
@@ -901,11 +821,7 @@ impl CalendarProtocol for JsObject {
         object_to_temporal_fields(&o, context).map_err(|e| TemporalError::general(e.to_string()))
     }
 
-    fn identifier(&self, context: &mut dyn Any) -> TemporalResult<String> {
-        let context = context
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomCalendar.");
-
+    fn identifier(&self, context: &mut Context) -> TemporalResult<String> {
         let identifier = self
             .__get__(
                 &PropertyKey::from(utf16!("id")),
diff --git a/core/engine/src/builtins/temporal/plain_date/mod.rs b/core/engine/src/builtins/temporal/plain_date/mod.rs
index 596e1bf400..06abf25a6c 100644
--- a/core/engine/src/builtins/temporal/plain_date/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_date/mod.rs
@@ -284,7 +284,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_year(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_year(&date, context)?.into())
     }
 
     /// 3.3.5 get `Temporal.PlainDate.prototype.month`
@@ -299,7 +299,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_month(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_month(&date, context)?.into())
     }
 
     /// 3.3.6 get Temporal.PlainDate.prototype.monthCode
@@ -314,10 +314,10 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(JsString::from(
-            InnerDate::<JsObject>::contextualized_month_code(&date, context)?.as_str(),
+        Ok(
+            JsString::from(InnerDate::<JsObject>::contextual_month_code(&date, context)?.as_str())
+                .into(),
         )
-        .into())
     }
 
     /// 3.3.7 get `Temporal.PlainDate.prototype.day`
@@ -332,7 +332,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_day(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_day(&date, context)?.into())
     }
 
     /// 3.3.8 get `Temporal.PlainDate.prototype.dayOfWeek`
@@ -347,7 +347,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_day_of_week(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_day_of_week(&date, context)?.into())
     }
 
     /// 3.3.9 get `Temporal.PlainDate.prototype.dayOfYear`
@@ -362,7 +362,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_day_of_year(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_day_of_year(&date, context)?.into())
     }
 
     /// 3.3.10 get `Temporal.PlainDate.prototype.weekOfYear`
@@ -377,7 +377,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_week_of_year(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_week_of_year(&date, context)?.into())
     }
 
     /// 3.3.11 get `Temporal.PlainDate.prototype.yearOfWeek`
@@ -392,7 +392,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_year_of_week(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_year_of_week(&date, context)?.into())
     }
 
     /// 3.3.12 get `Temporal.PlainDate.prototype.daysInWeek`
@@ -407,7 +407,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_days_in_week(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_days_in_week(&date, context)?.into())
     }
 
     /// 3.3.13 get `Temporal.PlainDate.prototype.daysInMonth`
@@ -426,7 +426,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_days_in_month(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_days_in_month(&date, context)?.into())
     }
 
     /// 3.3.14 get `Temporal.PlainDate.prototype.daysInYear`
@@ -441,7 +441,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_days_in_year(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_days_in_year(&date, context)?.into())
     }
 
     /// 3.3.15 get `Temporal.PlainDate.prototype.monthsInYear`
@@ -460,7 +460,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_months_in_year(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_months_in_year(&date, context)?.into())
     }
 
     /// 3.3.16 get `Temporal.PlainDate.prototype.inLeapYear`
@@ -475,7 +475,7 @@ impl PlainDate {
                 .into());
         };
 
-        Ok(InnerDate::<JsObject>::contextualized_in_leap_year(&date, context)?.into())
+        Ok(InnerDate::<JsObject>::contextual_in_leap_year(&date, context)?.into())
     }
 }
 
diff --git a/core/engine/src/builtins/temporal/plain_date_time/mod.rs b/core/engine/src/builtins/temporal/plain_date_time/mod.rs
index 143553edf2..9fb73aea04 100644
--- a/core/engine/src/builtins/temporal/plain_date_time/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_date_time/mod.rs
@@ -372,7 +372,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_year(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_year(&date, context)?.into())
     }
 
     /// 5.3.5 get `Temporal.PlainDateTime.prototype.month`
@@ -387,7 +387,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_month(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_month(&date, context)?.into())
     }
 
     /// 5.3.6 get Temporal.PlainDateTime.prototype.monthCode
@@ -403,7 +403,7 @@ impl PlainDateTime {
         };
 
         Ok(JsString::from(
-            InnerDateTime::<JsObject>::contextualized_month_code(&date, context)?.as_str(),
+            InnerDateTime::<JsObject>::contextual_month_code(&date, context)?.as_str(),
         )
         .into())
     }
@@ -420,7 +420,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_day(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_day(&date, context)?.into())
     }
 
     /// 5.3.8 get `Temporal.PlainDateTime.prototype.hour`
@@ -525,7 +525,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_day_of_week(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_day_of_week(&date, context)?.into())
     }
 
     /// 5.3.15 get `Temporal.PlainDateTime.prototype.dayOfYear`
@@ -540,7 +540,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_day_of_year(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_day_of_year(&date, context)?.into())
     }
 
     /// 5.3.16 get `Temporal.PlainDateTime.prototype.weekOfYear`
@@ -555,7 +555,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_week_of_year(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_week_of_year(&date, context)?.into())
     }
 
     /// 5.3.17 get `Temporal.PlainDateTime.prototype.yearOfWeek`
@@ -570,7 +570,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_year_of_week(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_year_of_week(&date, context)?.into())
     }
 
     /// 5.3.18 get `Temporal.PlainDateTime.prototype.daysInWeek`
@@ -585,7 +585,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_days_in_week(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_days_in_week(&date, context)?.into())
     }
 
     /// 5.3.19 get `Temporal.PlainDateTime.prototype.daysInMonth`
@@ -604,7 +604,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_days_in_month(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_days_in_month(&date, context)?.into())
     }
 
     /// 5.3.20 get `Temporal.PlainDateTime.prototype.daysInYear`
@@ -619,7 +619,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_days_in_year(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_days_in_year(&date, context)?.into())
     }
 
     /// 5.3.21 get `Temporal.PlainDateTime.prototype.monthsInYear`
@@ -638,7 +638,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_months_in_year(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_months_in_year(&date, context)?.into())
     }
 
     /// 5.3.22 get `Temporal.PlainDateTime.prototype.inLeapYear`
@@ -653,7 +653,7 @@ impl PlainDateTime {
                 .into());
         };
 
-        Ok(InnerDateTime::<JsObject>::contextualized_in_leap_year(&date, context)?.into())
+        Ok(InnerDateTime::<JsObject>::contextual_in_leap_year(&date, context)?.into())
     }
 }
 
diff --git a/core/engine/src/builtins/temporal/time_zone/custom.rs b/core/engine/src/builtins/temporal/time_zone/custom.rs
index a8aaf33aa2..344943b140 100644
--- a/core/engine/src/builtins/temporal/time_zone/custom.rs
+++ b/core/engine/src/builtins/temporal/time_zone/custom.rs
@@ -14,11 +14,8 @@ pub(crate) struct JsCustomTimeZone {
 }
 
 impl TzProtocol for JsCustomTimeZone {
-    fn get_offset_nanos_for(&self, ctx: &mut dyn std::any::Any) -> TemporalResult<BigInt> {
-        let context = ctx
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomTz");
-
+    type Context = Context;
+    fn get_offset_nanos_for(&self, context: &mut Context) -> TemporalResult<BigInt> {
         let method = self
             .tz
             .get(utf16!("getOffsetNanosFor"), context)
@@ -39,23 +36,12 @@ impl TzProtocol for JsCustomTimeZone {
         Ok(bigint.as_inner().clone())
     }
 
-    fn get_possible_instant_for(
-        &self,
-        ctx: &mut dyn std::any::Any,
-    ) -> TemporalResult<Vec<Instant>> {
-        let _context = ctx
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomTz");
-
+    fn get_possible_instant_for(&self, _context: &mut Context) -> TemporalResult<Vec<Instant>> {
         // TODO: Implement once Instant has been migrated to `boa_temporal`'s Instant.
         Err(TemporalError::range().with_message("Not yet implemented."))
     }
 
-    fn id(&self, ctx: &mut dyn std::any::Any) -> TemporalResult<String> {
-        let context = ctx
-            .downcast_mut::<Context>()
-            .expect("Context was not provided for a CustomTz");
-
+    fn id(&self, context: &mut Context) -> TemporalResult<String> {
         let ident = self
             .tz
             .__get__(
diff --git a/core/temporal/src/components/calendar.rs b/core/temporal/src/components/calendar.rs
index 22b9f3e6cd..9543cb8062 100644
--- a/core/temporal/src/components/calendar.rs
+++ b/core/temporal/src/components/calendar.rs
@@ -8,7 +8,7 @@
 //! the calendar protocol), but it does aim to provide the necessary tools and API for
 //! implementing one.
 
-use std::{any::Any, str::FromStr};
+use std::str::FromStr;
 
 use crate::{
     components::{Date, DateTime, Duration, MonthDay, YearMonth},
@@ -88,13 +88,13 @@ impl From<&[String]> for CalendarFieldsType {
 #[derive(Debug)]
 pub enum CalendarDateLike<C: CalendarProtocol> {
     /// Represents a user-defined `Date` datelike
-    CustomDate(<<C as CalendarProtocol>::DateLikes as DateTypes<C>>::Date),
+    CustomDate(C::Date),
     /// Represents a user-defined `DateTime` datelike
-    CustomDateTime(<<C as CalendarProtocol>::DateLikes as DateTypes<C>>::DateTime),
+    CustomDateTime(C::DateTime),
     /// Represents a user-defined `YearMonth` datelike
-    CustomYearMonth(<<C as CalendarProtocol>::DateLikes as DateTypes<C>>::YearMonth),
+    CustomYearMonth(C::YearMonth),
     /// Represents a user-defined `MonthDay` datelike
-    CustomMonthDay(<<C as CalendarProtocol>::DateLikes as DateTypes<C>>::MonthDay),
+    CustomMonthDay(C::MonthDay),
     /// Represents a `DateTime<C>`.
     DateTime(DateTime<C>),
     /// Represents a `Date<C>`.
@@ -117,45 +117,41 @@ impl<C: CalendarProtocol> CalendarDateLike<C> {
     }
 }
 
-// TODO: DateTypes should implement a trait -> `ToTemporalDate`: `GetCalendarSlot`
-/// A trait for implementing `DateLike` types
-pub trait DateTypes<C: CalendarProtocol> {
+// ==== CalendarProtocol trait ====
+
+/// A trait for implementing a Builtin Calendar's Calendar Protocol in Rust.
+pub trait CalendarProtocol: Clone {
     /// A Custom `Date` Type for an associated `CalendarProtocol`. Default `Date<C>`
-    type Date: IsoDateSlots + GetCalendarSlot<C> + Clone + core::fmt::Debug;
+    type Date: IsoDateSlots + GetCalendarSlot<Self> + Clone + core::fmt::Debug;
     /// A Custom `DateTime` Type for an associated `CalendarProtocol`. Default `DateTime<C>`
-    type DateTime: IsoDateSlots + GetCalendarSlot<C> + Clone + core::fmt::Debug;
+    type DateTime: IsoDateSlots + GetCalendarSlot<Self> + Clone + core::fmt::Debug;
     /// A Custom `YearMonth` Type for an associated `CalendarProtocol`. Default `YearMonth<C>`
-    type YearMonth: IsoDateSlots + GetCalendarSlot<C> + Clone + core::fmt::Debug;
+    type YearMonth: IsoDateSlots + GetCalendarSlot<Self> + Clone + core::fmt::Debug;
     /// A Custom `MonthDay` Type for an associated `CalendarProtocol`. Default `MonthDay<C>`
-    type MonthDay: IsoDateSlots + GetCalendarSlot<C> + Clone + core::fmt::Debug;
-}
-
-// ==== CalendarProtocol trait ====
+    type MonthDay: IsoDateSlots + GetCalendarSlot<Self> + Clone + core::fmt::Debug;
+    /// The context passed to every method of the `CalendarProtocol`.
+    type Context;
 
-/// A trait for implementing a Builtin Calendar's Calendar Protocol in Rust.
-pub trait CalendarProtocol: Clone {
-    /// Registers a valid set of custom `CalendarDateLike` values.
-    type DateLikes: DateTypes<Self>;
     /// Creates a `Temporal.PlainDate` object from provided fields.
     fn date_from_fields(
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<Date<Self>>;
     /// Creates a `Temporal.PlainYearMonth` object from the provided fields.
     fn year_month_from_fields(
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<YearMonth<Self>>;
     /// Creates a `Temporal.PlainMonthDay` object from the provided fields.
     fn month_day_from_fields(
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<MonthDay<Self>>;
     /// Returns a `Temporal.PlainDate` based off an added date.
     fn date_add(
@@ -163,7 +159,7 @@ pub trait CalendarProtocol: Clone {
         date: &Date<Self>,
         duration: &Duration,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<Date<Self>>;
     /// Returns a `Temporal.Duration` representing the duration between two dates.
     fn date_until(
@@ -171,106 +167,114 @@ pub trait CalendarProtocol: Clone {
         one: &Date<Self>,
         two: &Date<Self>,
         largest_unit: TemporalUnit,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<Duration>;
     /// Returns the era for a given `temporaldatelike`.
     fn era(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<Option<TinyAsciiStr<16>>>;
     /// Returns the era year for a given `temporaldatelike`
     fn era_year(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<Option<i32>>;
     /// Returns the `year` for a given `temporaldatelike`
     fn year(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<i32>;
     /// Returns the `month` for a given `temporaldatelike`
     fn month(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u8>;
     // Note: Best practice would probably be to switch to a MonthCode enum after extraction.
     /// Returns the `monthCode` for a given `temporaldatelike`
     fn month_code(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<TinyAsciiStr<4>>;
     /// Returns the `day` for a given `temporaldatelike`
-    fn day(&self, date_like: &CalendarDateLike<Self>, context: &mut dyn Any) -> TemporalResult<u8>;
+    fn day(
+        &self,
+        date_like: &CalendarDateLike<Self>,
+        context: &mut Self::Context,
+    ) -> TemporalResult<u8>;
     /// Returns a value representing the day of the week for a date.
     fn day_of_week(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u16>;
     /// Returns a value representing the day of the year for a given calendar.
     fn day_of_year(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u16>;
     /// Returns a value representing the week of the year for a given calendar.
     fn week_of_year(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u16>;
     /// Returns the year of a given week.
     fn year_of_week(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<i32>;
     /// Returns the days in a week for a given calendar.
     fn days_in_week(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u16>;
     /// Returns the days in a month for a given calendar.
     fn days_in_month(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u16>;
     /// Returns the days in a year for a given calendar.
     fn days_in_year(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u16>;
     /// Returns the months in a year for a given calendar.
     fn months_in_year(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<u16>;
     /// Returns whether a value is within a leap year according to the designated calendar.
     fn in_leap_year(
         &self,
         date_like: &CalendarDateLike<Self>,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<bool>;
     /// Return the fields for a value.
-    fn fields(&self, fields: Vec<String>, context: &mut dyn Any) -> TemporalResult<Vec<String>>;
+    fn fields(
+        &self,
+        fields: Vec<String>,
+        context: &mut Self::Context,
+    ) -> TemporalResult<Vec<String>>;
     /// Merge fields based on the calendar and provided values.
     fn merge_fields(
         &self,
         fields: &TemporalFields,
         additional_fields: &TemporalFields,
-        context: &mut dyn Any,
+        context: &mut Self::Context,
     ) -> TemporalResult<TemporalFields>;
     /// Debug name
-    fn identifier(&self, context: &mut dyn Any) -> TemporalResult<String>;
+    fn identifier(&self, context: &mut Self::Context) -> TemporalResult<String>;
 }
 
 /// A trait for retrieving an internal calendar slice.
@@ -369,7 +373,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Date<C>> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -412,7 +416,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<MonthDay<C>> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -440,7 +444,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
         &self,
         fields: &mut TemporalFields,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<YearMonth<C>> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -482,7 +486,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
         date: &Date<C>,
         duration: &Duration,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Date<C>> {
         match self {
             CalendarSlot::Builtin(_) => {
@@ -500,7 +504,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
         one: &Date<C>,
         two: &Date<C>,
         largest_unit: TemporalUnit,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Duration> {
         match self {
             CalendarSlot::Builtin(_) => {
@@ -516,7 +520,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn era(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Option<TinyAsciiStr<16>>> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(None),
@@ -532,7 +536,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn era_year(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Option<i32>> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(None),
@@ -548,7 +552,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn year(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<i32> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(date_like.as_iso_date().year),
@@ -564,7 +568,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn month(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u8> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(date_like.as_iso_date().month),
@@ -579,7 +583,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn month_code(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<TinyAsciiStr<4>> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -596,7 +600,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn day(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u8> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(date_like.as_iso_date().day),
@@ -611,7 +615,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn day_of_week(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -628,7 +632,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn day_of_year(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(date_like
@@ -647,7 +651,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn week_of_year(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -672,7 +676,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn year_of_week(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<i32> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -701,7 +705,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn days_in_week(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(7),
@@ -716,7 +720,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn days_in_month(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -734,7 +738,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn days_in_year(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -751,7 +755,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn months_in_year(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(12),
@@ -766,7 +770,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn in_leap_year(
         &self,
         date_like: &CalendarDateLike<C>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<bool> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => {
@@ -783,7 +787,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     pub fn fields(
         &self,
         fields: Vec<String>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Vec<String>> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(fields),
@@ -799,7 +803,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
         &self,
         fields: &TemporalFields,
         additional_fields: &TemporalFields,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<TemporalFields> {
         match self {
             CalendarSlot::Builtin(_) => fields.merge_fields(additional_fields, self),
@@ -810,7 +814,7 @@ impl<C: CalendarProtocol> CalendarSlot<C> {
     }
 
     /// Returns the identifier of this calendar slot.
-    pub fn identifier(&self, context: &mut dyn Any) -> TemporalResult<String> {
+    pub fn identifier(&self, context: &mut C::Context) -> TemporalResult<String> {
         match self {
             CalendarSlot::Builtin(AnyCalendar::Iso(_)) => Ok(String::from("iso8601")),
             CalendarSlot::Builtin(builtin) => Ok(String::from(builtin.debug_name())),
@@ -857,25 +861,27 @@ impl IsoDateSlots for () {
     }
 }
 
-impl DateTypes<()> for () {
-    type Date = Date<()>;
-    type DateTime = DateTime<()>;
-    type YearMonth = YearMonth<()>;
-    type MonthDay = MonthDay<()>;
-}
-
 /// An empty `CalendarProtocol` implementation on `()`.
 ///
 /// # Panics
 ///
 /// Attempting to use this empty calendar implementation as a valid calendar is an error and will cause a panic.
 impl CalendarProtocol for () {
-    type DateLikes = ();
+    type Date = Date<()>;
+
+    type DateTime = DateTime<()>;
+
+    type YearMonth = YearMonth<()>;
+
+    type MonthDay = MonthDay<()>;
+
+    type Context = ();
+
     fn date_from_fields(
         &self,
         _: &mut TemporalFields,
         _: ArithmeticOverflow,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<Date<Self>> {
         unreachable!();
     }
@@ -884,7 +890,7 @@ impl CalendarProtocol for () {
         &self,
         _: &mut TemporalFields,
         _: ArithmeticOverflow,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<MonthDay<()>> {
         unreachable!();
     }
@@ -893,7 +899,7 @@ impl CalendarProtocol for () {
         &self,
         _: &mut TemporalFields,
         _: ArithmeticOverflow,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<YearMonth<Self>> {
         unreachable!()
     }
@@ -903,7 +909,7 @@ impl CalendarProtocol for () {
         _: &Date<Self>,
         _: &Duration,
         _: ArithmeticOverflow,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<Date<Self>> {
         unreachable!();
     }
@@ -913,7 +919,7 @@ impl CalendarProtocol for () {
         _: &Date<()>,
         _: &Date<()>,
         _: TemporalUnit,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<Duration> {
         unreachable!();
     }
@@ -921,72 +927,72 @@ impl CalendarProtocol for () {
     fn era(
         &self,
         _: &CalendarDateLike<Self>,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<Option<TinyAsciiStr<16>>> {
         unreachable!();
     }
 
-    fn era_year(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<Option<i32>> {
+    fn era_year(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<Option<i32>> {
         unreachable!();
     }
 
-    fn year(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<i32> {
+    fn year(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<i32> {
         unreachable!();
     }
 
-    fn month(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u8> {
+    fn month(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u8> {
         unreachable!();
     }
 
     fn month_code(
         &self,
         _: &CalendarDateLike<Self>,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<TinyAsciiStr<4>> {
         unreachable!();
     }
 
-    fn day(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u8> {
+    fn day(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u8> {
         unreachable!();
     }
 
-    fn day_of_week(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u16> {
+    fn day_of_week(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u16> {
         unreachable!();
     }
 
-    fn day_of_year(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u16> {
+    fn day_of_year(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u16> {
         unreachable!();
     }
 
-    fn week_of_year(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u16> {
+    fn week_of_year(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u16> {
         unreachable!();
     }
 
-    fn year_of_week(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<i32> {
+    fn year_of_week(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<i32> {
         unreachable!();
     }
 
-    fn days_in_week(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u16> {
+    fn days_in_week(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u16> {
         unreachable!();
     }
 
-    fn days_in_month(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u16> {
+    fn days_in_month(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u16> {
         unreachable!();
     }
 
-    fn days_in_year(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u16> {
+    fn days_in_year(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u16> {
         unreachable!();
     }
 
-    fn months_in_year(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<u16> {
+    fn months_in_year(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<u16> {
         unreachable!();
     }
 
-    fn in_leap_year(&self, _: &CalendarDateLike<Self>, _: &mut dyn Any) -> TemporalResult<bool> {
+    fn in_leap_year(&self, _: &CalendarDateLike<Self>, (): &mut ()) -> TemporalResult<bool> {
         unreachable!();
     }
 
-    fn fields(&self, _: Vec<String>, _: &mut dyn Any) -> TemporalResult<Vec<String>> {
+    fn fields(&self, _: Vec<String>, (): &mut ()) -> TemporalResult<Vec<String>> {
         unreachable!();
     }
 
@@ -994,12 +1000,12 @@ impl CalendarProtocol for () {
         &self,
         _: &TemporalFields,
         _: &TemporalFields,
-        _: &mut dyn Any,
+        (): &mut (),
     ) -> TemporalResult<TemporalFields> {
         unreachable!();
     }
 
-    fn identifier(&self, _: &mut dyn Any) -> TemporalResult<String> {
+    fn identifier(&self, (): &mut ()) -> TemporalResult<String> {
         unreachable!();
     }
 }
diff --git a/core/temporal/src/components/date.rs b/core/temporal/src/components/date.rs
index 0b768035f2..d6c80eb265 100644
--- a/core/temporal/src/components/date.rs
+++ b/core/temporal/src/components/date.rs
@@ -13,10 +13,10 @@ use crate::{
     parser::parse_date_time,
     TemporalError, TemporalResult,
 };
-use std::{any::Any, str::FromStr};
+use std::str::FromStr;
 
 use super::{
-    calendar::{CalendarDateLike, DateTypes, GetCalendarSlot},
+    calendar::{CalendarDateLike, GetCalendarSlot},
     duration::TimeDuration,
 };
 
@@ -42,7 +42,7 @@ impl<C: CalendarProtocol> Date<C> {
     pub(crate) fn move_relative_date(
         &self,
         duration: &Duration,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<(Self, f64)> {
         let new_date =
             self.contextual_add_date(duration, ArithmeticOverflow::Constrain, context)?;
@@ -215,117 +215,102 @@ impl Date<()> {
 // reference count increment. Need to test.
 impl<C: CalendarProtocol> Date<C> {
     /// Returns the calendar year value with provided context.
-    pub fn contextualized_year(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
-    ) -> TemporalResult<i32> {
+    pub fn contextual_year(this: &C::Date, context: &mut C::Context) -> TemporalResult<i32> {
         this.get_calendar()
             .year(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar month value with provided context.
-    pub fn contextualized_month(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
-    ) -> TemporalResult<u8> {
+    pub fn contextual_month(this: &C::Date, context: &mut C::Context) -> TemporalResult<u8> {
         this.get_calendar()
             .month(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar month code value with provided context.
-    pub fn contextualized_month_code(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_month_code(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<TinyAsciiStr<4>> {
         this.get_calendar()
             .month_code(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar day value with provided context.
-    pub fn contextualized_day(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
-    ) -> TemporalResult<u8> {
+    pub fn contextual_day(this: &C::Date, context: &mut C::Context) -> TemporalResult<u8> {
         this.get_calendar()
             .day(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar day of week value with provided context.
-    pub fn contextualized_day_of_week(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
-    ) -> TemporalResult<u16> {
+    pub fn contextual_day_of_week(this: &C::Date, context: &mut C::Context) -> TemporalResult<u16> {
         this.get_calendar()
             .day_of_week(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar day of year value with provided context.
-    pub fn contextualized_day_of_year(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
-    ) -> TemporalResult<u16> {
+    pub fn contextual_day_of_year(this: &C::Date, context: &mut C::Context) -> TemporalResult<u16> {
         this.get_calendar()
             .day_of_year(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar week of year value with provided context.
-    pub fn contextualized_week_of_year(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_week_of_year(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .week_of_year(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar year of week value with provided context.
-    pub fn contextualized_year_of_week(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_year_of_week(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<i32> {
         this.get_calendar()
             .year_of_week(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar days in week value with provided context.
-    pub fn contextualized_days_in_week(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_days_in_week(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .days_in_week(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar days in month value with provided context.
-    pub fn contextualized_days_in_month(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_days_in_month(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .days_in_month(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar days in year value with provided context.
-    pub fn contextualized_days_in_year(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_days_in_year(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .days_in_year(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns the calendar months in year value with provided context.
-    pub fn contextualized_months_in_year(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_months_in_year(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .months_in_year(&CalendarDateLike::CustomDate(this.clone()), context)
     }
 
     /// Returns whether the date is in a leap year for the given calendar with provided context.
-    pub fn contextualized_in_leap_year(
-        this: &<C::DateLikes as DateTypes<C>>::Date,
-        context: &mut dyn Any,
+    pub fn contextual_in_leap_year(
+        this: &C::Date,
+        context: &mut C::Context,
     ) -> TemporalResult<bool> {
         this.get_calendar()
             .in_leap_year(&CalendarDateLike::CustomDate(this.clone()), context)
@@ -356,7 +341,7 @@ impl<C: CalendarProtocol> Date<C> {
         &self,
         duration: &Duration,
         overflow: ArithmeticOverflow,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Self> {
         // 1. If options is not present, set options to undefined.
         // 2. If duration.[[Years]] ≠ 0, or duration.[[Months]] ≠ 0, or duration.[[Weeks]] ≠ 0, then
@@ -391,18 +376,6 @@ impl<C: CalendarProtocol> Date<C> {
         Ok(Self::new_unchecked(result, self.calendar().clone()))
     }
 
-    /// Returns the date after adding the given duration to date.
-    ///
-    /// Temporal Equivalent: 3.5.13 `AddDate ( calendar, plainDate, duration [ , options [ , dateAdd ] ] )`
-    #[inline]
-    pub fn add_date(
-        &self,
-        duration: &Duration,
-        overflow: ArithmeticOverflow,
-    ) -> TemporalResult<Self> {
-        self.contextual_add_date(duration, overflow, &mut ())
-    }
-
     /// Returns a duration representing the difference between the dates one and two with a provided context.
     ///
     /// Temporal Equivalent: 3.5.6 `DifferenceDate ( calendar, one, two, options )`
@@ -411,7 +384,7 @@ impl<C: CalendarProtocol> Date<C> {
         &self,
         other: &Self,
         largest_unit: TemporalUnit,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<Duration> {
         if self.iso.year == other.iso.year
             && self.iso.month == other.iso.month
@@ -433,18 +406,6 @@ impl<C: CalendarProtocol> Date<C> {
         self.calendar()
             .date_until(self, other, largest_unit, context)
     }
-
-    /// Returns a duration representing the difference between the dates one and two.
-    ///
-    /// Temporal Equivalent: 3.5.6 `DifferenceDate ( calendar, one, two, options )`
-    #[inline]
-    pub fn difference_date(
-        &self,
-        other: &Self,
-        largest_unit: TemporalUnit,
-    ) -> TemporalResult<Duration> {
-        self.contextual_difference_date(other, largest_unit, &mut ())
-    }
 }
 
 // ==== Trait impls ====
diff --git a/core/temporal/src/components/datetime.rs b/core/temporal/src/components/datetime.rs
index 1dfc69f3f9..1a5197c6fb 100644
--- a/core/temporal/src/components/datetime.rs
+++ b/core/temporal/src/components/datetime.rs
@@ -11,10 +11,10 @@ use crate::{
     TemporalError, TemporalResult,
 };
 
-use std::{any::Any, str::FromStr};
+use std::str::FromStr;
 use tinystr::TinyAsciiStr;
 
-use super::calendar::{CalendarDateLike, DateTypes, GetCalendarSlot};
+use super::calendar::{CalendarDateLike, GetCalendarSlot};
 
 /// The native Rust implementation of `Temporal.PlainDateTime`
 #[derive(Debug, Default, Clone)]
@@ -248,117 +248,108 @@ impl DateTime<()> {
 
 impl<C: CalendarProtocol> DateTime<C> {
     /// Returns the calendar year value with provided context.
-    pub fn contextualized_year(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
-    ) -> TemporalResult<i32> {
+    pub fn contextual_year(this: &C::DateTime, context: &mut C::Context) -> TemporalResult<i32> {
         this.get_calendar()
             .year(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar month value with provided context.
-    pub fn contextualized_month(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
-    ) -> TemporalResult<u8> {
+    pub fn contextual_month(this: &C::DateTime, context: &mut C::Context) -> TemporalResult<u8> {
         this.get_calendar()
             .month(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar month code value with provided context.
-    pub fn contextualized_month_code(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_month_code(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<TinyAsciiStr<4>> {
         this.get_calendar()
             .month_code(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar day value with provided context.
-    pub fn contextualized_day(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
-    ) -> TemporalResult<u8> {
+    pub fn contextual_day(this: &C::DateTime, context: &mut C::Context) -> TemporalResult<u8> {
         this.get_calendar()
             .day(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar day of week value with provided context.
-    pub fn contextualized_day_of_week(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_day_of_week(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .day_of_week(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar day of year value with provided context.
-    pub fn contextualized_day_of_year(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_day_of_year(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .day_of_year(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar week of year value with provided context.
-    pub fn contextualized_week_of_year(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_week_of_year(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .week_of_year(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar year of week value with provided context.
-    pub fn contextualized_year_of_week(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_year_of_week(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<i32> {
         this.get_calendar()
             .year_of_week(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar days in week value with provided context.
-    pub fn contextualized_days_in_week(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_days_in_week(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .days_in_week(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar days in month value with provided context.
-    pub fn contextualized_days_in_month(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_days_in_month(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .days_in_month(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar days in year value with provided context.
-    pub fn contextualized_days_in_year(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_days_in_year(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .days_in_year(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns the calendar months in year value with provided context.
-    pub fn contextualized_months_in_year(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_months_in_year(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<u16> {
         this.get_calendar()
             .months_in_year(&CalendarDateLike::CustomDateTime(this.clone()), context)
     }
 
     /// Returns whether the date is in a leap year for the given calendar with provided context.
-    pub fn contextualized_in_leap_year(
-        this: &<C::DateLikes as DateTypes<C>>::DateTime,
-        context: &mut dyn Any,
+    pub fn contextual_in_leap_year(
+        this: &C::DateTime,
+        context: &mut C::Context,
     ) -> TemporalResult<bool> {
         this.get_calendar()
             .in_leap_year(&CalendarDateLike::CustomDateTime(this.clone()), context)
diff --git a/core/temporal/src/components/duration.rs b/core/temporal/src/components/duration.rs
index 8486064bcf..13205dc465 100644
--- a/core/temporal/src/components/duration.rs
+++ b/core/temporal/src/components/duration.rs
@@ -6,7 +6,7 @@ use crate::{
     parser::{duration::parse_duration, Cursor},
     TemporalError, TemporalResult,
 };
-use std::{any::Any, str::FromStr};
+use std::str::FromStr;
 
 use super::{calendar::CalendarProtocol, tz::TzProtocol};
 
@@ -370,7 +370,7 @@ impl Duration {
         &self,
         largest_unit: TemporalUnit,
         plain_relative_to: Option<&Date<C>>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<DateDuration> {
         // 1. Let allZero be false.
         // 2. If years = 0, and months = 0, and weeks = 0, and days = 0, set allZero to true.
@@ -576,7 +576,7 @@ impl Duration {
         &self,
         largest_unit: TemporalUnit,
         plain_relative_to: Option<&Date<C>>,
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<DateDuration> {
         let mut result = self.date;
 
@@ -816,7 +816,7 @@ impl Duration {
             Option<&ZonedDateTime<C, Z>>,
             Option<&DateTime<C>>,
         ),
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<(Self, f64)> {
         match unit {
             TemporalUnit::Year | TemporalUnit::Month | TemporalUnit::Week | TemporalUnit::Day => {
diff --git a/core/temporal/src/components/duration/date.rs b/core/temporal/src/components/duration/date.rs
index 2fec74995d..9f83097928 100644
--- a/core/temporal/src/components/duration/date.rs
+++ b/core/temporal/src/components/duration/date.rs
@@ -9,8 +9,6 @@ use crate::{
     utils, TemporalError, TemporalResult, NS_PER_DAY,
 };
 
-use std::any::Any;
-
 /// `DateDuration` represents the [date duration record][spec] of the `Duration.`
 ///
 /// These fields are laid out in the [Temporal Proposal][field spec] as 64-bit floating point numbers.
@@ -147,7 +145,7 @@ impl DateDuration {
             Option<&ZonedDateTime<C, Z>>,
             Option<&DateTime<C>>,
         ),
-        context: &mut dyn Any,
+        context: &mut C::Context,
     ) -> TemporalResult<(Self, f64)> {
         // 1. If plainRelativeTo is not present, set plainRelativeTo to undefined.
         let plain_relative_to = relative_targets.0;
diff --git a/core/temporal/src/components/tz.rs b/core/temporal/src/components/tz.rs
index 6a83f3fedf..4deb4b0674 100644
--- a/core/temporal/src/components/tz.rs
+++ b/core/temporal/src/components/tz.rs
@@ -1,7 +1,5 @@
 //! This module implements the Temporal `TimeZone` and components.
 
-use std::any::Any;
-
 use num_bigint::BigInt;
 use num_traits::ToPrimitive;
 
@@ -18,12 +16,15 @@ pub const TIME_ZONE_PROPERTIES: [&str; 3] =
 
 /// The Time Zone Protocol that must be implemented for time zones.
 pub trait TzProtocol: Clone {
+    /// The context passed to every method of the `TzProtocol`.
+    type Context;
     /// Get the Offset nanoseconds for this `TimeZone`
-    fn get_offset_nanos_for(&self, context: &mut dyn Any) -> TemporalResult<BigInt>;
+    fn get_offset_nanos_for(&self, context: &mut Self::Context) -> TemporalResult<BigInt>;
     /// Get the possible Instant for this `TimeZone`
-    fn get_possible_instant_for(&self, context: &mut dyn Any) -> TemporalResult<Vec<Instant>>; // TODO: Implement Instant
+    fn get_possible_instant_for(&self, context: &mut Self::Context)
+        -> TemporalResult<Vec<Instant>>; // TODO: Implement Instant
     /// Get the `TimeZone`'s identifier.
-    fn id(&self, context: &mut dyn Any) -> TemporalResult<String>;
+    fn id(&self, context: &mut Self::Context) -> TemporalResult<String>;
 }
 
 /// A Temporal `TimeZone`.
@@ -57,7 +58,7 @@ impl<Z: TzProtocol> TimeZoneSlot<Z> {
         &self,
         instant: &Instant,
         calendar: &CalendarSlot<C>,
-        context: &mut dyn Any,
+        context: &mut Z::Context,
     ) -> TemporalResult<DateTime<C>> {
         let nanos = self.get_offset_nanos_for(context)?;
         DateTime::from_instant(instant, nanos.to_f64().unwrap_or(0.0), calendar.clone())
@@ -66,7 +67,7 @@ impl<Z: TzProtocol> TimeZoneSlot<Z> {
 
 impl<Z: TzProtocol> TimeZoneSlot<Z> {
     /// Get the offset for this current `TimeZoneSlot`.
-    pub fn get_offset_nanos_for(&self, context: &mut dyn Any) -> TemporalResult<BigInt> {
+    pub fn get_offset_nanos_for(&self, context: &mut Z::Context) -> TemporalResult<BigInt> {
         // 1. Let timeZone be the this value.
         // 2. Perform ? RequireInternalSlot(timeZone, [[InitializedTemporalTimeZone]]).
         // 3. Set instant to ? ToTemporalInstant(instant).
@@ -85,12 +86,15 @@ impl<Z: TzProtocol> TimeZoneSlot<Z> {
     }
 
     /// Get the possible `Instant`s for this `TimeZoneSlot`.
-    pub fn get_possible_instant_for(&self, _context: &mut dyn Any) -> TemporalResult<Vec<Instant>> {
+    pub fn get_possible_instant_for(
+        &self,
+        _context: &mut Z::Context,
+    ) -> TemporalResult<Vec<Instant>> {
         Err(TemporalError::general("Not yet implemented."))
     }
 
     /// Returns the current `TimeZoneSlot`'s identifier.
-    pub fn id(&self, context: &mut dyn Any) -> TemporalResult<String> {
+    pub fn id(&self, context: &mut Z::Context) -> TemporalResult<String> {
         match self {
             Self::Tz(_) => Err(TemporalError::range().with_message("Not yet implemented.")), // TODO: Implement Display for Time Zone.
             Self::Protocol(tz) => tz.id(context),
@@ -99,15 +103,16 @@ impl<Z: TzProtocol> TimeZoneSlot<Z> {
 }
 
 impl TzProtocol for () {
-    fn get_offset_nanos_for(&self, _: &mut dyn Any) -> TemporalResult<BigInt> {
+    type Context = ();
+    fn get_offset_nanos_for(&self, (): &mut ()) -> TemporalResult<BigInt> {
         unreachable!()
     }
 
-    fn get_possible_instant_for(&self, _: &mut dyn Any) -> TemporalResult<Vec<Instant>> {
+    fn get_possible_instant_for(&self, (): &mut ()) -> TemporalResult<Vec<Instant>> {
         unreachable!()
     }
 
-    fn id(&self, _: &mut dyn Any) -> TemporalResult<String> {
+    fn id(&self, (): &mut ()) -> TemporalResult<String> {
         Ok("() TimeZone".to_owned())
     }
 }
diff --git a/core/temporal/src/components/zoneddatetime.rs b/core/temporal/src/components/zoneddatetime.rs
index 489efd1f6d..04d72941af 100644
--- a/core/temporal/src/components/zoneddatetime.rs
+++ b/core/temporal/src/components/zoneddatetime.rs
@@ -12,8 +12,6 @@ use crate::{
     TemporalResult,
 };
 
-use core::any::Any;
-
 use super::tz::TzProtocol;
 
 /// The native Rust implementation of `Temporal.ZonedDateTime`.
@@ -98,24 +96,21 @@ impl<C: CalendarProtocol, Z: TzProtocol> ZonedDateTime<C, Z> {
 
 // ==== Context based API ====
 
-impl<C: CalendarProtocol, Z: TzProtocol> ZonedDateTime<C, Z> {
+impl<C, Z: TzProtocol> ZonedDateTime<C, Z>
+where
+    C: CalendarProtocol<Context = Z::Context>,
+{
     /// Returns the `year` value for this `ZonedDateTime`.
     #[inline]
-    pub fn contextual_year(&self, context: &mut dyn Any) -> TemporalResult<i32> {
+    pub fn contextual_year(&self, context: &mut C::Context) -> TemporalResult<i32> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         self.calendar.year(&CalendarDateLike::DateTime(dt), context)
     }
 
-    /// Returns the `year` value for this `ZonedDateTime`.
-    #[inline]
-    pub fn year(&self) -> TemporalResult<i32> {
-        self.contextual_year(&mut ())
-    }
-
     /// Returns the `month` value for this `ZonedDateTime`.
-    pub fn contextual_month(&self, context: &mut dyn Any) -> TemporalResult<u8> {
+    pub fn contextual_month(&self, context: &mut C::Context) -> TemporalResult<u8> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
@@ -123,14 +118,8 @@ impl<C: CalendarProtocol, Z: TzProtocol> ZonedDateTime<C, Z> {
             .month(&CalendarDateLike::DateTime(dt), context)
     }
 
-    /// Returns the `month` value for this `ZonedDateTime`.
-    #[inline]
-    pub fn month(&self) -> TemporalResult<u8> {
-        self.contextual_month(&mut ())
-    }
-
     /// Returns the `monthCode` value for this `ZonedDateTime`.
-    pub fn contextual_month_code(&self, context: &mut dyn Any) -> TemporalResult<TinyStr4> {
+    pub fn contextual_month_code(&self, context: &mut C::Context) -> TemporalResult<TinyStr4> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
@@ -138,102 +127,61 @@ impl<C: CalendarProtocol, Z: TzProtocol> ZonedDateTime<C, Z> {
             .month_code(&CalendarDateLike::DateTime(dt), context)
     }
 
-    /// Returns the `monthCode` value for this `ZonedDateTime`.
-    #[inline]
-    pub fn month_code(&self) -> TemporalResult<TinyStr4> {
-        self.contextual_month_code(&mut ())
-    }
-
     /// Returns the `day` value for this `ZonedDateTime`.
-    pub fn contextual_day(&self, context: &mut dyn Any) -> TemporalResult<u8> {
+    pub fn contextual_day(&self, context: &mut C::Context) -> TemporalResult<u8> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         self.calendar.day(&CalendarDateLike::DateTime(dt), context)
     }
 
-    /// Returns the `day` value for this `ZonedDateTime`.
-    pub fn day(&self) -> TemporalResult<u8> {
-        self.contextual_day(&mut ())
-    }
-
     /// Returns the `hour` value for this `ZonedDateTime`.
-    pub fn contextual_hour(&self, context: &mut dyn Any) -> TemporalResult<u8> {
+    pub fn contextual_hour(&self, context: &mut C::Context) -> TemporalResult<u8> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         Ok(dt.hour())
     }
 
-    /// Returns the `hour` value for this `ZonedDateTime`.
-    pub fn hour(&self) -> TemporalResult<u8> {
-        self.contextual_hour(&mut ())
-    }
-
     /// Returns the `minute` value for this `ZonedDateTime`.
-    pub fn contextual_minute(&self, context: &mut dyn Any) -> TemporalResult<u8> {
+    pub fn contextual_minute(&self, context: &mut C::Context) -> TemporalResult<u8> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         Ok(dt.minute())
     }
 
-    /// Returns the `minute` value for this `ZonedDateTime`.
-    pub fn minute(&self) -> TemporalResult<u8> {
-        self.contextual_minute(&mut ())
-    }
-
     /// Returns the `second` value for this `ZonedDateTime`.
-    pub fn contextual_second(&self, context: &mut dyn Any) -> TemporalResult<u8> {
+    pub fn contextual_second(&self, context: &mut C::Context) -> TemporalResult<u8> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         Ok(dt.second())
     }
 
-    /// Returns the `second` value for this `ZonedDateTime`.
-    pub fn second(&self) -> TemporalResult<u8> {
-        self.contextual_second(&mut ())
-    }
-
     /// Returns the `millisecond` value for this `ZonedDateTime`.
-    pub fn contextual_millisecond(&self, context: &mut dyn Any) -> TemporalResult<u16> {
+    pub fn contextual_millisecond(&self, context: &mut C::Context) -> TemporalResult<u16> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         Ok(dt.millisecond())
     }
 
-    /// Returns the `millisecond` value for this `ZonedDateTime`.
-    pub fn millisecond(&self) -> TemporalResult<u16> {
-        self.contextual_millisecond(&mut ())
-    }
-
     /// Returns the `microsecond` value for this `ZonedDateTime`.
-    pub fn contextual_microsecond(&self, context: &mut dyn Any) -> TemporalResult<u16> {
+    pub fn contextual_microsecond(&self, context: &mut C::Context) -> TemporalResult<u16> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         Ok(dt.millisecond())
     }
 
-    /// Returns the `microsecond` value for this `ZonedDateTime`.
-    pub fn microsecond(&self) -> TemporalResult<u16> {
-        self.contextual_microsecond(&mut ())
-    }
-
     /// Returns the `nanosecond` value for this `ZonedDateTime`.
-    pub fn contextual_nanosecond(&self, context: &mut dyn Any) -> TemporalResult<u16> {
+    pub fn contextual_nanosecond(&self, context: &mut C::Context) -> TemporalResult<u16> {
         let dt = self
             .tz
             .get_datetime_for(&self.instant, &self.calendar, context)?;
         Ok(dt.nanosecond())
     }
-
-    /// Returns the `nanosecond` value for this `ZonedDateTime`.
-    pub fn nanosecond(&self) -> TemporalResult<u16> {
-        self.contextual_nanosecond(&mut ())
-    }
 }
 
 #[cfg(test)]
@@ -259,12 +207,12 @@ mod tests {
         )
         .unwrap();
 
-        assert_eq!(zdt.year().unwrap(), 2023);
-        assert_eq!(zdt.month().unwrap(), 11);
-        assert_eq!(zdt.day().unwrap(), 30);
-        assert_eq!(zdt.hour().unwrap(), 1);
-        assert_eq!(zdt.minute().unwrap(), 49);
-        assert_eq!(zdt.second().unwrap(), 12);
+        assert_eq!(zdt.contextual_year(&mut ()).unwrap(), 2023);
+        assert_eq!(zdt.contextual_month(&mut ()).unwrap(), 11);
+        assert_eq!(zdt.contextual_day(&mut ()).unwrap(), 30);
+        assert_eq!(zdt.contextual_hour(&mut ()).unwrap(), 1);
+        assert_eq!(zdt.contextual_minute(&mut ()).unwrap(), 49);
+        assert_eq!(zdt.contextual_second(&mut ()).unwrap(), 12);
 
         let zdt_minus_five = ZonedDateTime::<(), ()>::new(
             nov_30_2023_utc,
@@ -276,11 +224,11 @@ mod tests {
         )
         .unwrap();
 
-        assert_eq!(zdt_minus_five.year().unwrap(), 2023);
-        assert_eq!(zdt_minus_five.month().unwrap(), 11);
-        assert_eq!(zdt_minus_five.day().unwrap(), 29);
-        assert_eq!(zdt_minus_five.hour().unwrap(), 20);
-        assert_eq!(zdt_minus_five.minute().unwrap(), 49);
-        assert_eq!(zdt_minus_five.second().unwrap(), 12);
+        assert_eq!(zdt_minus_five.contextual_year(&mut ()).unwrap(), 2023);
+        assert_eq!(zdt_minus_five.contextual_month(&mut ()).unwrap(), 11);
+        assert_eq!(zdt_minus_five.contextual_day(&mut ()).unwrap(), 29);
+        assert_eq!(zdt_minus_five.contextual_hour(&mut ()).unwrap(), 20);
+        assert_eq!(zdt_minus_five.contextual_minute(&mut ()).unwrap(), 49);
+        assert_eq!(zdt_minus_five.contextual_second(&mut ()).unwrap(), 12);
     }
 }