diff --git a/Project.toml b/Project.toml
index 0d38933e..6f8f559c 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "ITensorNetworks"
 uuid = "2919e153-833c-4bdc-8836-1ea460a35fc7"
-version = "0.21.0"
+version = "0.21.1"
 authors = ["Matthew Fishman <mfishman@flatironinstitute.org>, Joseph Tindall <jtindall@flatironinstitute.org> and contributors"]
 
 [workspace]
@@ -39,12 +39,10 @@ TupleTools = "9d95972d-f1c8-5527-a6e0-b4b365fa01f6"
 
 [weakdeps]
 OMEinsumContractionOrders = "6f22d1fd-8eed-4bb7-9776-e7d684900715"
-Observers = "338f10d5-c7f1-4033-a7d1-f9dec39bcaa0"
 TensorOperations = "6aa20fa7-93e2-5fca-9bc0-fbd0db3c71a2"
 
 [extensions]
 ITensorNetworksOMEinsumContractionOrdersExt = "OMEinsumContractionOrders"
-ITensorNetworksObserversExt = "Observers"
 ITensorNetworksTensorOperationsExt = "TensorOperations"
 
 [compat]
@@ -67,7 +65,6 @@ MacroTools = "0.5"
 NDTensors = "0.3, 0.4"
 NamedGraphs = "0.11"
 OMEinsumContractionOrders = "0.8.3, 0.9, 1"
-Observers = "0.2.4"
 SerializedElementArrays = "0.1"
 SimpleTraits = "0.9"
 SplitApplyCombine = "1.2"
diff --git a/ext/ITensorNetworksObserversExt/ITensorNetworksObserversExt.jl b/ext/ITensorNetworksObserversExt/ITensorNetworksObserversExt.jl
deleted file mode 100644
index 340d3d9e..00000000
--- a/ext/ITensorNetworksObserversExt/ITensorNetworksObserversExt.jl
+++ /dev/null
@@ -1,9 +0,0 @@
-module ITensorNetworksObserversExt
-using ITensorNetworks: ITensorNetworks
-using Observers.DataFrames: AbstractDataFrame
-using Observers: Observers
-
-function ITensorNetworks.update_observer!(observer::AbstractDataFrame; kwargs...)
-    return Observers.update!(observer; kwargs...)
-end
-end
diff --git a/test/Project.toml b/test/Project.toml
index c861b038..708ec90f 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -19,7 +19,6 @@ Metis = "2679e427-3c69-5b7f-982b-ece356f1e94b"
 NDTensors = "23ae76d9-e61a-49c4-8f12-3f1a16adf9cf"
 NamedGraphs = "678767b0-92e7-4007-89e4-4527a8725b19"
 OMEinsumContractionOrders = "6f22d1fd-8eed-4bb7-9776-e7d684900715"
-Observers = "338f10d5-c7f1-4033-a7d1-f9dec39bcaa0"
 Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 SafeTestsets = "1bc83da4-3b8d-516f-aca4-4fe02f6d838f"
@@ -55,7 +54,6 @@ Metis = "1.5"
 NDTensors = "0.3, 0.4"
 NamedGraphs = "0.11"
 OMEinsumContractionOrders = "0.9.5, 1"
-Observers = "0.2.5"
 Pkg = "1.10"
 Random = "1.10"
 SafeTestsets = "0.1"