diff --git a/.gitignore b/.gitignore
index 6eb156e..c0506f0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@
 **/*.rs.bk
 Cargo.lock
 .env
+.venv
 dist/
\ No newline at end of file
diff --git a/Cargo.toml b/Cargo.toml
index d7ff25e..1b2e412 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hifitime"
-version = "3.8.6"
+version = "3.8.7"
 authors = ["Christopher Rabotin <christopher.rabotin@gmail.com>"]
 description = "Ultra-precise date and time handling in Rust for scientific applications with leap second support"
 homepage = "https://nyxspace.com/"
@@ -20,7 +20,7 @@ name = "hifitime"
 [dependencies]
 serde = { version = "1.0.155", optional = true }
 serde_derive = { version = "1.0.155", optional = true }
-der = { version = "0.6.1", features = ["derive", "real"], optional = true }
+der = { version = "0.7.8", features = ["derive", "real"], optional = true }
 pyo3 = { version = "0.20.0", features = ["extension-module"], optional = true }
 num-traits = { version = "0.2.15", default-features = false, features = [
     "libm",
@@ -34,19 +34,31 @@ tabled = { version = "0.15.0", optional = true }
 openssl = { version = "0.10", features = ["vendored"], optional = true }
 
 [target.wasm32-unknown-unknown.dependencies]
-js-sys = { version = "0.3"}
-wasm-bindgen_rs = { package = "wasm-bindgen", version = "0.2"}
-web-sys = { version = "0.3", features = ['Window', 'Performance', 'PerformanceTiming'] }
+js-sys = { version = "0.3" }
+wasm-bindgen_rs = { package = "wasm-bindgen", version = "0.2" }
+web-sys = { version = "0.3", features = [
+    'Window',
+    'Performance',
+    'PerformanceTiming',
+] }
 
 [target.wasm32-unknown-emscripten.dependencies]
-js-sys = { version = "0.3"}
-wasm-bindgen_rs = { package = "wasm-bindgen", version = "0.2"}
-web-sys = { version = "0.3", features = ['Window', 'Performance', 'PerformanceTiming'] }
+js-sys = { version = "0.3" }
+wasm-bindgen_rs = { package = "wasm-bindgen", version = "0.2" }
+web-sys = { version = "0.3", features = [
+    'Window',
+    'Performance',
+    'PerformanceTiming',
+] }
 
 [target.asmjs-unknown-emscripten.dependencies]
-js-sys = { version = "0.3"}
-wasm-bindgen_rs = { package = "wasm-bindgen", version = "0.2"}
-web-sys = { version = "0.3", features = ['Window', 'Performance', 'PerformanceTiming'] }
+js-sys = { version = "0.3" }
+wasm-bindgen_rs = { package = "wasm-bindgen", version = "0.2" }
+web-sys = { version = "0.3", features = [
+    'Window',
+    'Performance',
+    'PerformanceTiming',
+] }
 
 [dev-dependencies]
 serde_json = "1.0.91"
diff --git a/README.md b/README.md
index 3f57bbe..2bd4337 100644
--- a/README.md
+++ b/README.md
@@ -309,6 +309,10 @@ In order to provide full interoperability with NAIF, hifitime uses the NAIF algo
 
 # Changelog
 
+## 3.8.7
+
+Update to der version 0.7.x.
+
 ## 3.8.5
 
 Changes from 3.8.2 are only dependency upgrades until this release.
diff --git a/src/asn1der.rs b/src/asn1der.rs
index 0dbc2ba..45a7f1a 100644
--- a/src/asn1der.rs
+++ b/src/asn1der.rs
@@ -21,7 +21,7 @@ impl Encode for Duration {
         centuries.encoded_len()? + nanoseconds.encoded_len()?
     }
 
-    fn encode(&self, encoder: &mut dyn Writer) -> der::Result<()> {
+    fn encode(&self, encoder: &mut impl Writer) -> der::Result<()> {
         let (centuries, nanoseconds) = self.to_parts();
         centuries.encode(encoder)?;
         nanoseconds.encode(encoder)
@@ -43,7 +43,7 @@ impl Encode for Epoch {
         ts.encoded_len()? + self.to_duration().encoded_len()?
     }
 
-    fn encode(&self, encoder: &mut dyn Writer) -> der::Result<()> {
+    fn encode(&self, encoder: &mut impl Writer) -> der::Result<()> {
         let ts: u8 = self.time_scale.into();
 
         ts.encode(encoder)?;
@@ -76,7 +76,7 @@ impl Encode for Unit {
         converted.encoded_len()
     }
 
-    fn encode(&self, encoder: &mut dyn Writer) -> der::Result<()> {
+    fn encode(&self, encoder: &mut impl Writer) -> der::Result<()> {
         let converted: u8 = self.into();
         converted.encode(encoder)
     }
diff --git a/src/duration.rs b/src/duration.rs
index 43260d8..d8403c5 100644
--- a/src/duration.rs
+++ b/src/duration.rs
@@ -62,6 +62,7 @@ pub const NANOSECONDS_PER_CENTURY: u64 = DAYS_PER_CENTURY_U64 * NANOSECONDS_PER_
 #[derive(Clone, Copy, Debug, PartialOrd, Eq, Ord)]
 #[repr(C)]
 #[cfg_attr(feature = "python", pyclass)]
+#[cfg_attr(feature = "python", pyo3(module = "hifitime"))]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct Duration {
     pub(crate) centuries: i16,
@@ -694,6 +695,11 @@ impl Duration {
         }
     }
 
+    #[cfg(feature = "python")]
+    fn __getnewargs__(&self) -> Result<(String,), PyErr> {
+        Ok((format!("{self}"),))
+    }
+
     #[cfg(feature = "python")]
     fn __str__(&self) -> String {
         format!("{self}")
@@ -701,7 +707,7 @@ impl Duration {
 
     #[cfg(feature = "python")]
     fn __repr__(&self) -> String {
-        format!("{self}")
+        format!("{self} @ {self:p}")
     }
 
     #[cfg(feature = "python")]
diff --git a/src/efmt/consts.rs b/src/efmt/consts.rs
index 3c2f21e..657fad6 100644
--- a/src/efmt/consts.rs
+++ b/src/efmt/consts.rs
@@ -453,3 +453,61 @@ pub const RFC2822_LONG: Format = Format {
     ],
     num_items: 7,
 };
+
+/// The ISO8601 format without the time scale
+pub const ISO8601_STD: Format = Format {
+    items: [
+        Some(Item {
+            token: Token::Year,
+            sep_char: Some('-'),
+            second_sep_char: None,
+            optional: false,
+        }),
+        Some(Item {
+            token: Token::Month,
+            sep_char: Some('-'),
+            second_sep_char: None,
+            optional: false,
+        }),
+        Some(Item {
+            token: Token::Day,
+            sep_char: Some('T'),
+            second_sep_char: None,
+            optional: false,
+        }),
+        Some(Item {
+            token: Token::Hour,
+            sep_char: Some(':'),
+            second_sep_char: None,
+            optional: false,
+        }),
+        Some(Item {
+            token: Token::Minute,
+            sep_char: Some(':'),
+            second_sep_char: None,
+            optional: false,
+        }),
+        Some(Item {
+            token: Token::Second,
+            sep_char: Some('.'),
+            second_sep_char: None,
+            optional: false,
+        }),
+        Some(Item {
+            token: Token::Subsecond,
+            sep_char: Some(' '),
+            optional: false,
+            second_sep_char: None,
+        }),
+        None,
+        None,
+        None,
+        None,
+        None,
+        None,
+        None,
+        None,
+        None,
+    ],
+    num_items: 7,
+};
diff --git a/src/epoch.rs b/src/epoch.rs
index 24c625f..e859258 100644
--- a/src/epoch.rs
+++ b/src/epoch.rs
@@ -124,6 +124,7 @@ const CUMULATIVE_DAYS_FOR_MONTH: [u16; 12] = {
 #[derive(Copy, Clone, Eq, Default)]
 #[repr(C)]
 #[cfg_attr(feature = "python", pyclass)]
+#[cfg_attr(feature = "python", pyo3(module = "hifitime"))]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct Epoch {
     /// An Epoch is always stored as the duration of since J1900 in the TAI time scale.
@@ -1687,13 +1688,13 @@ impl Epoch {
 
     #[cfg(feature = "python")]
     #[classmethod]
-    /// Equivalent to `datetime.strptime, refer to <https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html> for format options
+    /// Equivalent to `datetime.strptime`, refer to <https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html> for format options
     fn strptime(_cls: &PyType, epoch_str: String, format_str: String) -> PyResult<Self> {
         Self::from_format_str(&epoch_str, &format_str).map_err(|e| PyErr::from(e))
     }
 
     #[cfg(feature = "python")]
-    /// Equivalent to `datetime.strftime, refer to <https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html> for format options
+    /// Equivalent to `datetime.strftime`, refer to <https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html> for format options
     fn strftime(&self, format_str: String) -> PyResult<String> {
         use crate::efmt::Formatter;
         let fmt = Format::from_str(&format_str)
@@ -1702,6 +1703,21 @@ impl Epoch {
         Ok(format!("{}", Formatter::new(*self, fmt)))
     }
 
+    #[cfg(feature = "python")]
+    /// Equivalent to `datetime.isoformat`, and truncated to 23 chars, refer to <https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html> for format options
+    fn isoformat(&self) -> PyResult<String> {
+        Ok(self.to_isoformat())
+    }
+
+    #[cfg(feature = "std")]
+    #[must_use]
+    /// The standard ISO format of this epoch (six digits of subseconds), refer to <https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html> for format options
+    pub fn to_isoformat(&self) -> String {
+        use crate::efmt::consts::ISO8601_STD;
+        use crate::efmt::Formatter;
+        format!("{}", Formatter::new(*self, ISO8601_STD))[..26].to_string()
+    }
+
     /// Returns this epoch with respect to the time scale this epoch was created in.
     /// This is needed to correctly perform duration conversions in dynamical time scales (e.g. TDB).
     ///
@@ -2673,6 +2689,11 @@ impl Epoch {
         }
     }
 
+    #[cfg(feature = "python")]
+    fn __getnewargs__(&self) -> Result<(String,), PyErr> {
+        Ok((format!("{self:?}"),))
+    }
+
     #[cfg(feature = "python")]
     #[classmethod]
     fn system_now(_cls: &PyType) -> Result<Self, Errors> {
@@ -2686,7 +2707,7 @@ impl Epoch {
 
     #[cfg(feature = "python")]
     fn __repr__(&self) -> String {
-        format!("{self:?}")
+        format!("{self:?} @ {self:p}")
     }
 
     #[cfg(feature = "python")]
diff --git a/src/leap_seconds.rs b/src/leap_seconds.rs
index a02f166..195f498 100644
--- a/src/leap_seconds.rs
+++ b/src/leap_seconds.rs
@@ -105,7 +105,7 @@ impl LatestLeapSeconds {
     }
 
     fn __repr__(&self) -> String {
-        format!("{self:?}")
+        format!("{self:?} @ {self:p}")
     }
 }
 
diff --git a/src/leap_seconds_file.rs b/src/leap_seconds_file.rs
index efbad59..0c613ca 100644
--- a/src/leap_seconds_file.rs
+++ b/src/leap_seconds_file.rs
@@ -87,7 +87,7 @@ impl LeapSecondsFile {
     }
 
     fn __repr__(&self) -> String {
-        format!("{self:?}")
+        format!("{self:?} @ {self:p}")
     }
 }
 
diff --git a/src/timeseries.rs b/src/timeseries.rs
index d04fded..c31dc61 100644
--- a/src/timeseries.rs
+++ b/src/timeseries.rs
@@ -17,6 +17,13 @@ use num_traits::Float;
 
 #[cfg(feature = "python")]
 use pyo3::prelude::*;
+
+#[cfg(feature = "python")]
+use pyo3::pyclass::CompareOp;
+
+#[cfg(feature = "python")]
+use pyo3::exceptions::PyTypeError;
+
 /*
 
 NOTE: This is taken from itertools: https://docs.rs/itertools-num/0.1.3/src/itertools_num/linspace.rs.html#78-93 .
@@ -26,6 +33,7 @@ NOTE: This is taken from itertools: https://docs.rs/itertools-num/0.1.3/src/iter
 /// An iterator of a sequence of evenly spaced Epochs.
 #[derive(Clone, Debug, PartialEq, Eq)]
 #[cfg_attr(feature = "python", pyclass)]
+#[cfg_attr(feature = "python", pyo3(module = "hifitime"))]
 pub struct TimeSeries {
     start: Epoch,
     duration: Duration,
@@ -222,6 +230,10 @@ impl TimeSeries {
         }
     }
 
+    fn __getnewargs__(&self) -> Result<(Epoch, Epoch, Duration, bool), PyErr> {
+        Ok((self.start, self.start + self.duration, self.step, self.incl))
+    }
+
     fn __iter__(slf: PyRef<'_, Self>) -> PyRef<'_, Self> {
         slf
     }
@@ -235,7 +247,12 @@ impl TimeSeries {
     }
 
     fn __repr__(&self) -> String {
-        format!("{self}")
+        format!("{self:?} @ {self:p}")
+    }
+
+    #[cfg(feature = "python")]
+    fn __eq__(&self, other: Self) -> bool {
+        *self == other
     }
 }
 
diff --git a/src/ut1.rs b/src/ut1.rs
index bf3a360..9c491b2 100644
--- a/src/ut1.rs
+++ b/src/ut1.rs
@@ -129,7 +129,7 @@ impl Ut1Provider {
     }
 
     fn __repr__(&self) -> String {
-        format!("{self}")
+        format!("{self:?} @ {self:p}")
     }
 }
 
diff --git a/tests/efmt.rs b/tests/efmt.rs
index 8612f42..2089ac5 100644
--- a/tests/efmt.rs
+++ b/tests/efmt.rs
@@ -15,6 +15,19 @@ fn epoch_parse_with_format() {
     assert_eq!(ISO8601_FLEX.parse("2015-02-07T11:22:33.0 UTC").unwrap(), e);
     assert_eq!(ISO8601_FLEX.parse("2015-02-07T11:22:33").unwrap(), e);
 
+    assert_eq!(ISO8601_STD.parse("2015-02-07T11:22:33.0").unwrap(), e);
+
+    #[cfg(feature = "std")]
+    {
+        // Test an epoch that's much more precise than usual time keepers
+        let e_prec = Epoch::from_gregorian_utc(2015, 2, 7, 11, 22, 33, 123456789);
+        assert_eq!(e_prec.to_isoformat(), "2015-02-07T11:22:33.123456");
+        assert_ne!(
+            e_prec.to_isoformat(),
+            Formatter::new(e_prec, ISO8601).to_string()
+        );
+    }
+
     assert_eq!(RFC3339.parse("2015-02-07T11:22:33.0 UTC").unwrap(), e);
 
     assert!(RFC3339.parse("2018-02-13T23:08:32Z").is_ok());
diff --git a/tests/python/test_epoch.py b/tests/python/test_epoch.py
index 1e39c8f..2b32ba6 100644
--- a/tests/python/test_epoch.py
+++ b/tests/python/test_epoch.py
@@ -1,5 +1,6 @@
 from hifitime import Epoch, TimeSeries, Unit, Duration
 from datetime import datetime
+import pickle
 
 
 def test_strtime():
@@ -16,6 +17,8 @@ def test_strtime():
 
     assert Epoch.strptime(dt_fmt, "%A, %d %B %Y %H:%M:%S") == epoch
 
+    assert pickle.loads(pickle.dumps(epoch)) == epoch
+
 
 def test_utcnow():
     epoch = Epoch.system_now()
@@ -40,10 +43,16 @@ def test_time_series():
     )
     print(time_series)
 
+    assert pickle.loads(pickle.dumps(time_series)) == time_series
+
     for num, epoch in enumerate(time_series):
         print(f"#{num}:\t{epoch}")
 
     assert num == 10
+    # Once consummed, the iterator in the time series will be different,
+    # so the pickling will return something different
+    assert pickle.loads(pickle.dumps(time_series)) != time_series
+
 
 def test_duration_eq():
     """
@@ -54,4 +63,7 @@ def test_duration_eq():
     assert Unit.Second * 1.0 >= Duration("0 ns")
     assert Unit.Second * 1.0 > Duration("0 ns")
     assert Duration("0 ns") <= Unit.Second * 1.0
-    assert Duration("0 ns") < Unit.Second * 1.0
\ No newline at end of file
+    assert Duration("0 ns") < Unit.Second * 1.0
+
+    dur = Duration("37 min 26 s")
+    assert pickle.loads(pickle.dumps(dur)) == dur