diff --git a/Cargo.lock b/Cargo.lock
index c0e30e7c59..4a884ef108 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1201,7 +1201,7 @@ checksum = "6dbf3de79e51f3d586ab4cb9d5c3e2c14aa28ed23d180cf89b4df0454a69cc87"
 
 [[package]]
 name = "hugr"
-version = "0.20.2"
+version = "0.21.0"
 dependencies = [
  "bumpalo",
  "criterion",
@@ -1216,7 +1216,7 @@ dependencies = [
 
 [[package]]
 name = "hugr-cli"
-version = "0.20.2"
+version = "0.21.0"
 dependencies = [
  "anyhow",
  "assert_cmd",
@@ -1237,7 +1237,7 @@ dependencies = [
 
 [[package]]
 name = "hugr-core"
-version = "0.20.2"
+version = "0.21.0"
 dependencies = [
  "anyhow",
  "base64",
@@ -1282,7 +1282,7 @@ dependencies = [
 
 [[package]]
 name = "hugr-llvm"
-version = "0.20.2"
+version = "0.21.0"
 dependencies = [
  "anyhow",
  "delegate",
@@ -1301,7 +1301,7 @@ dependencies = [
 
 [[package]]
 name = "hugr-model"
-version = "0.20.2"
+version = "0.21.0"
 dependencies = [
  "base64",
  "bumpalo",
@@ -1325,7 +1325,7 @@ dependencies = [
 
 [[package]]
 name = "hugr-passes"
-version = "0.20.2"
+version = "0.21.0"
 dependencies = [
  "ascent",
  "derive_more 1.0.0",
diff --git a/hugr-cli/CHANGELOG.md b/hugr-cli/CHANGELOG.md
index 5bbc26a608..5c498a199f 100644
--- a/hugr-cli/CHANGELOG.md
+++ b/hugr-cli/CHANGELOG.md
@@ -1,6 +1,12 @@
 # Changelog
 
 
+## [0.21.0](https://github.com/CQCL/hugr/compare/hugr-cli-v0.20.2...hugr-cli-v0.21.0) - 2025-07-09
+
+### New Features
+
+- [**breaking**] Better error reporting in `hugr-cli`. ([#2318](https://github.com/CQCL/hugr/pull/2318))
+
 ## [0.20.2](https://github.com/CQCL/hugr/compare/hugr-cli-v0.20.1...hugr-cli-v0.20.2) - 2025-06-25
 
 ### New Features
diff --git a/hugr-cli/Cargo.toml b/hugr-cli/Cargo.toml
index 003ed92ee7..964967ca79 100644
--- a/hugr-cli/Cargo.toml
+++ b/hugr-cli/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hugr-cli"
-version = "0.20.2"
+version = "0.21.0"
 edition = { workspace = true }
 rust-version = { workspace = true }
 license = { workspace = true }
@@ -19,7 +19,7 @@ bench = false
 clap = { workspace = true, features = ["derive", "cargo"] }
 clap-verbosity-flag.workspace = true
 derive_more = { workspace = true, features = ["display", "error", "from"] }
-hugr = { path = "../hugr", version = "0.20.2" }
+hugr = { path = "../hugr", version = "0.21.0" }
 serde_json.workspace = true
 clio = { workspace = true, features = ["clap-parse"] }
 anyhow.workspace = true
diff --git a/hugr-core/CHANGELOG.md b/hugr-core/CHANGELOG.md
index 9026431a7a..28aee65198 100644
--- a/hugr-core/CHANGELOG.md
+++ b/hugr-core/CHANGELOG.md
@@ -1,5 +1,48 @@
 # Changelog
 
+## [0.21.0](https://github.com/CQCL/hugr/compare/hugr-core-v0.20.2...hugr-core-v0.21.0) - 2025-07-09
+
+### Bug Fixes
+
+- Fixed two bugs in import/export of function operations ([#2324](https://github.com/CQCL/hugr/pull/2324))
+- Model import should perform extension resolution ([#2326](https://github.com/CQCL/hugr/pull/2326))
+- [**breaking**] Fixed bugs in model CFG handling and improved CFG signatures ([#2334](https://github.com/CQCL/hugr/pull/2334))
+- Use List instead of Tuple in conversions for TypeArg/TypeRow ([#2378](https://github.com/CQCL/hugr/pull/2378))
+- Do extension resolution on loaded extensions from the model format ([#2389](https://github.com/CQCL/hugr/pull/2389))
+- Make JSON Schema checks actually work again ([#2412](https://github.com/CQCL/hugr/pull/2412))
+- Order hints on input and output nodes. ([#2422](https://github.com/CQCL/hugr/pull/2422))
+
+### New Features
+
+- [**breaking**] No nested FuncDefns (or AliasDefns) ([#2256](https://github.com/CQCL/hugr/pull/2256))
+- [**breaking**] Split `TypeArg::Sequence` into tuples and lists. ([#2140](https://github.com/CQCL/hugr/pull/2140))
+- [**breaking**] Added float and bytes literal to core and python bindings. ([#2289](https://github.com/CQCL/hugr/pull/2289))
+- [**breaking**] More helpful error messages in model import ([#2272](https://github.com/CQCL/hugr/pull/2272))
+- [**breaking**] Better error reporting in `hugr-cli`. ([#2318](https://github.com/CQCL/hugr/pull/2318))
+- [**breaking**] Merge `TypeParam` and `TypeArg` into one `Term` type in Rust ([#2309](https://github.com/CQCL/hugr/pull/2309))
+- *(persistent)* Add serialisation for CommitStateSpace ([#2344](https://github.com/CQCL/hugr/pull/2344))
+- add TryFrom impls for TypeArg/TypeRow ([#2366](https://github.com/CQCL/hugr/pull/2366))
+- Add `MakeError` op ([#2377](https://github.com/CQCL/hugr/pull/2377))
+- Open lists and tuples in `Term` ([#2360](https://github.com/CQCL/hugr/pull/2360))
+- Call `FunctionBuilder::add_{in,out}put` for any AsMut<Hugr> ([#2376](https://github.com/CQCL/hugr/pull/2376))
+- Add Root checked methods to DataflowParentID ([#2382](https://github.com/CQCL/hugr/pull/2382))
+- Add PersistentWire type ([#2361](https://github.com/CQCL/hugr/pull/2361))
+- Add `BorrowArray` extension ([#2395](https://github.com/CQCL/hugr/pull/2395))
+- [**breaking**] Rename 'Any' type bound to 'Linear' ([#2421](https://github.com/CQCL/hugr/pull/2421))
+- [**breaking**] Add Visibility to FuncDefn/FuncDecl. ([#2143](https://github.com/CQCL/hugr/pull/2143))
+- *(per)* [**breaking**] Support empty wires in commits ([#2349](https://github.com/CQCL/hugr/pull/2349))
+- [**breaking**] hugr-model use explicit Option<Visibility>, with ::Unspecified in capnp ([#2424](https://github.com/CQCL/hugr/pull/2424))
+
+### Refactor
+
+- [**breaking**] move PersistentHugr into separate crate ([#2277](https://github.com/CQCL/hugr/pull/2277))
+- [**breaking**] remove deprecated runtime extension errors ([#2369](https://github.com/CQCL/hugr/pull/2369))
+- [**breaking**] Reduce error type sizes ([#2420](https://github.com/CQCL/hugr/pull/2420))
+
+### Testing
+
+- Check hugr json serializations against the schema (again) ([#2216](https://github.com/CQCL/hugr/pull/2216))
+
 ## [0.20.2](https://github.com/CQCL/hugr/compare/hugr-core-v0.20.1...hugr-core-v0.20.2) - 2025-06-25
 
 ### Documentation
diff --git a/hugr-core/Cargo.toml b/hugr-core/Cargo.toml
index 946fda2018..4ee6baf4a4 100644
--- a/hugr-core/Cargo.toml
+++ b/hugr-core/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hugr-core"
-version = "0.20.2"
+version = "0.21.0"
 edition = { workspace = true }
 rust-version = { workspace = true }
 
@@ -28,7 +28,7 @@ bench = false
 name = "model"
 
 [dependencies]
-hugr-model = { version = "0.20.2", path = "../hugr-model" }
+hugr-model = { version = "0.21.0", path = "../hugr-model" }
 
 cgmath = { workspace = true, features = ["serde"] }
 delegate = { workspace = true }
diff --git a/hugr-llvm/CHANGELOG.md b/hugr-llvm/CHANGELOG.md
index 0ed47be85a..936fa57f03 100644
--- a/hugr-llvm/CHANGELOG.md
+++ b/hugr-llvm/CHANGELOG.md
@@ -5,6 +5,16 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 
+## [0.21.0](https://github.com/CQCL/hugr/compare/hugr-llvm-v0.20.2...hugr-llvm-v0.21.0) - 2025-07-09
+
+### New Features
+
+- [**breaking**] No nested FuncDefns (or AliasDefns) ([#2256](https://github.com/CQCL/hugr/pull/2256))
+- [**breaking**] Split `TypeArg::Sequence` into tuples and lists. ([#2140](https://github.com/CQCL/hugr/pull/2140))
+- [**breaking**] More helpful error messages in model import ([#2272](https://github.com/CQCL/hugr/pull/2272))
+- [**breaking**] Merge `TypeParam` and `TypeArg` into one `Term` type in Rust ([#2309](https://github.com/CQCL/hugr/pull/2309))
+- Add `MakeError` op ([#2377](https://github.com/CQCL/hugr/pull/2377))
+
 ## [0.20.2](https://github.com/CQCL/hugr/compare/hugr-llvm-v0.20.1...hugr-llvm-v0.20.2) - 2025-06-25
 
 ### New Features
diff --git a/hugr-llvm/Cargo.toml b/hugr-llvm/Cargo.toml
index 4d7e9d198a..dee032ede0 100644
--- a/hugr-llvm/Cargo.toml
+++ b/hugr-llvm/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hugr-llvm"
-version = "0.20.2"
+version = "0.21.0"
 description = "A general and extensible crate for lowering HUGRs into LLVM IR"
 
 edition.workspace = true
@@ -26,7 +26,7 @@ workspace = true
 
 [dependencies]
 inkwell = { version = "0.6.0", default-features = false }
-hugr-core = { path = "../hugr-core", version = "0.20.1" }
+hugr-core = { path = "../hugr-core", version = "0.21.0" }
 anyhow.workspace = true
 itertools.workspace = true
 delegate.workspace = true
diff --git a/hugr-model/CHANGELOG.md b/hugr-model/CHANGELOG.md
index 901f077d14..fbfb9a2593 100644
--- a/hugr-model/CHANGELOG.md
+++ b/hugr-model/CHANGELOG.md
@@ -1,5 +1,20 @@
 # Changelog
 
+## [0.21.0](https://github.com/CQCL/hugr/compare/hugr-model-v0.20.2...hugr-model-v0.21.0) - 2025-07-09
+
+### Bug Fixes
+
+- Model import should perform extension resolution ([#2326](https://github.com/CQCL/hugr/pull/2326))
+- [**breaking**] Fixed bugs in model CFG handling and improved CFG signatures ([#2334](https://github.com/CQCL/hugr/pull/2334))
+- [**breaking**] Fix panic in model resolver when variable is used outside of symbol. ([#2362](https://github.com/CQCL/hugr/pull/2362))
+- Order hints on input and output nodes. ([#2422](https://github.com/CQCL/hugr/pull/2422))
+
+### New Features
+
+- [**breaking**] Added float and bytes literal to core and python bindings. ([#2289](https://github.com/CQCL/hugr/pull/2289))
+- [**breaking**] Add Visibility to FuncDefn/FuncDecl. ([#2143](https://github.com/CQCL/hugr/pull/2143))
+- [**breaking**] hugr-model use explicit Option<Visibility>, with ::Unspecified in capnp ([#2424](https://github.com/CQCL/hugr/pull/2424))
+
 ## [0.20.2](https://github.com/CQCL/hugr/compare/hugr-model-v0.20.1...hugr-model-v0.20.2) - 2025-06-25
 
 ### New Features
diff --git a/hugr-model/Cargo.toml b/hugr-model/Cargo.toml
index 24c1f9e42e..aca5528904 100644
--- a/hugr-model/Cargo.toml
+++ b/hugr-model/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hugr-model"
-version = "0.20.2"
+version = "0.21.0"
 readme = "README.md"
 documentation = "https://docs.rs/hugr-model/"
 description = "Data model for Quantinuum's HUGR intermediate representation"
diff --git a/hugr-passes/CHANGELOG.md b/hugr-passes/CHANGELOG.md
index d5f2921845..08698b8cf4 100644
--- a/hugr-passes/CHANGELOG.md
+++ b/hugr-passes/CHANGELOG.md
@@ -1,6 +1,23 @@
 # Changelog
 
 
+## [0.21.0](https://github.com/CQCL/hugr/compare/hugr-passes-v0.20.2...hugr-passes-v0.21.0) - 2025-07-09
+
+### Bug Fixes
+
+- DeadFuncElimPass+CallGraph w/ non-module-child entrypoint ([#2390](https://github.com/CQCL/hugr/pull/2390))
+
+### New Features
+
+- [**breaking**] No nested FuncDefns (or AliasDefns) ([#2256](https://github.com/CQCL/hugr/pull/2256))
+- [**breaking**] Split `TypeArg::Sequence` into tuples and lists. ([#2140](https://github.com/CQCL/hugr/pull/2140))
+- [**breaking**] Merge `TypeParam` and `TypeArg` into one `Term` type in Rust ([#2309](https://github.com/CQCL/hugr/pull/2309))
+- [**breaking**] Rename 'Any' type bound to 'Linear' ([#2421](https://github.com/CQCL/hugr/pull/2421))
+
+### Refactor
+
+- [**breaking**] Reduce error type sizes ([#2420](https://github.com/CQCL/hugr/pull/2420))
+
 ## [0.20.2](https://github.com/CQCL/hugr/compare/hugr-passes-v0.20.1...hugr-passes-v0.20.2) - 2025-06-25
 
 ### Bug Fixes
diff --git a/hugr-passes/Cargo.toml b/hugr-passes/Cargo.toml
index 8c1daafbcd..bd37426d75 100644
--- a/hugr-passes/Cargo.toml
+++ b/hugr-passes/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hugr-passes"
-version = "0.20.2"
+version = "0.21.0"
 edition = { workspace = true }
 rust-version = { workspace = true }
 license = { workspace = true }
@@ -19,7 +19,7 @@ workspace = true
 bench = false
 
 [dependencies]
-hugr-core = { path = "../hugr-core", version = "0.20.2" }
+hugr-core = { path = "../hugr-core", version = "0.21.0" }
 portgraph = { workspace = true }
 ascent = { version = "0.8.0" }
 derive_more = { workspace = true, features = ["display", "error", "from"] }
diff --git a/hugr-py/Cargo.toml b/hugr-py/Cargo.toml
index 27020c8122..4a4c6f11a4 100644
--- a/hugr-py/Cargo.toml
+++ b/hugr-py/Cargo.toml
@@ -21,6 +21,6 @@ bench = false
 
 [dependencies]
 bumpalo = { workspace = true, features = ["collections"] }
-hugr-model = { version = "0.20.2", path = "../hugr-model", features = ["pyo3"] }
+hugr-model = { version = "0.21.0", path = "../hugr-model", features = ["pyo3"] }
 paste.workspace = true
 pyo3 = { workspace = true, features = ["extension-module", "abi3-py310"] }
diff --git a/hugr/CHANGELOG.md b/hugr/CHANGELOG.md
index 46439ca695..71f1549c8e 100644
--- a/hugr/CHANGELOG.md
+++ b/hugr/CHANGELOG.md
@@ -1,5 +1,62 @@
 # Changelog
 
+## [0.21.0](https://github.com/CQCL/hugr/compare/hugr-v0.20.2...hugr-v0.21.0) - 2025-07-09
+
+
+This release includes a long list of changes:
+
+- The HUGR model serialization format is now stable, and should be preferred over the old JSON format.
+- Type parameters and type arguments are now unified into a single `Term` type.
+- Function definitions can no longer be nested inside dataflow regions. Now they must be defined at the top level module.
+- Function definitions and declarations now have a `Visibility` field, which define whether they are visible in the public API of the module.
+- And many more fixes and improvements.
+
+### Bug Fixes
+
+- DeadFuncElimPass+CallGraph w/ non-module-child entrypoint ([#2390](https://github.com/CQCL/hugr/pull/2390))
+- Fixed two bugs in import/export of function operations ([#2324](https://github.com/CQCL/hugr/pull/2324))
+- Model import should perform extension resolution ([#2326](https://github.com/CQCL/hugr/pull/2326))
+- [**breaking**] Fixed bugs in model CFG handling and improved CFG signatures ([#2334](https://github.com/CQCL/hugr/pull/2334))
+- Use List instead of Tuple in conversions for TypeArg/TypeRow ([#2378](https://github.com/CQCL/hugr/pull/2378))
+- Do extension resolution on loaded extensions from the model format ([#2389](https://github.com/CQCL/hugr/pull/2389))
+- Make JSON Schema checks actually work again ([#2412](https://github.com/CQCL/hugr/pull/2412))
+- Order hints on input and output nodes. ([#2422](https://github.com/CQCL/hugr/pull/2422))
+
+### Documentation
+
+- Hide hugr-persistent docs ([#2357](https://github.com/CQCL/hugr/pull/2357))
+
+### New Features
+
+- [**breaking**] Split `TypeArg::Sequence` into tuples and lists. ([#2140](https://github.com/CQCL/hugr/pull/2140))
+- [**breaking**] Added float and bytes literal to core and python bindings. ([#2289](https://github.com/CQCL/hugr/pull/2289))
+- [**breaking**] More helpful error messages in model import ([#2272](https://github.com/CQCL/hugr/pull/2272))
+- [**breaking**] Better error reporting in `hugr-cli`. ([#2318](https://github.com/CQCL/hugr/pull/2318))
+- [**breaking**] Merge `TypeParam` and `TypeArg` into one `Term` type in Rust ([#2309](https://github.com/CQCL/hugr/pull/2309))
+- *(persistent)* Add serialisation for CommitStateSpace ([#2344](https://github.com/CQCL/hugr/pull/2344))
+- add TryFrom impls for TypeArg/TypeRow ([#2366](https://github.com/CQCL/hugr/pull/2366))
+- Add `MakeError` op ([#2377](https://github.com/CQCL/hugr/pull/2377))
+- Open lists and tuples in `Term` ([#2360](https://github.com/CQCL/hugr/pull/2360))
+- Call `FunctionBuilder::add_{in,out}put` for any AsMut<Hugr> ([#2376](https://github.com/CQCL/hugr/pull/2376))
+- Add Root checked methods to DataflowParentID ([#2382](https://github.com/CQCL/hugr/pull/2382))
+- Add PersistentWire type ([#2361](https://github.com/CQCL/hugr/pull/2361))
+- Add `BorrowArray` extension ([#2395](https://github.com/CQCL/hugr/pull/2395))
+- [**breaking**] Add Visibility to FuncDefn/FuncDecl. ([#2143](https://github.com/CQCL/hugr/pull/2143))
+- *(per)* [**breaking**] Support empty wires in commits ([#2349](https://github.com/CQCL/hugr/pull/2349))
+- [**breaking**] hugr-model use explicit Option<Visibility>, with ::Unspecified in capnp ([#2424](https://github.com/CQCL/hugr/pull/2424))
+- [**breaking**] No nested FuncDefns (or AliasDefns) ([#2256](https://github.com/CQCL/hugr/pull/2256))
+- [**breaking**] Rename 'Any' type bound to 'Linear' ([#2421](https://github.com/CQCL/hugr/pull/2421))
+
+### Refactor
+
+- [**breaking**] remove deprecated runtime extension errors ([#2369](https://github.com/CQCL/hugr/pull/2369))
+- [**breaking**] Reduce error type sizes ([#2420](https://github.com/CQCL/hugr/pull/2420))
+- [**breaking**] move PersistentHugr into separate crate ([#2277](https://github.com/CQCL/hugr/pull/2277))
+
+### Testing
+
+- Check hugr json serializations against the schema (again) ([#2216](https://github.com/CQCL/hugr/pull/2216))
+
 ## [0.20.2](https://github.com/CQCL/hugr/compare/hugr-v0.20.1...hugr-v0.20.2) - 2025-06-25
 
 ### Bug Fixes
diff --git a/hugr/Cargo.toml b/hugr/Cargo.toml
index 439386c250..80c285a6c0 100644
--- a/hugr/Cargo.toml
+++ b/hugr/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hugr"
-version = "0.20.2"
+version = "0.21.0"
 edition = { workspace = true }
 rust-version = { workspace = true }
 
@@ -31,10 +31,10 @@ zstd = ["hugr-core/zstd"]
 persistent_unstable = ["hugr-persistent"]
 
 [dependencies]
-hugr-model = { path = "../hugr-model", version = "0.20.2" }
-hugr-core = { path = "../hugr-core", version = "0.20.2" }
-hugr-passes = { path = "../hugr-passes", version = "0.20.2" }
-hugr-llvm = { path = "../hugr-llvm", version = "0.20.2", optional = true }
+hugr-model = { path = "../hugr-model", version = "0.21.0" }
+hugr-core = { path = "../hugr-core", version = "0.21.0" }
+hugr-passes = { path = "../hugr-passes", version = "0.21.0" }
+hugr-llvm = { path = "../hugr-llvm", version = "0.21.0", optional = true }
 hugr-persistent = { path = "../hugr-persistent", version = "0.1.0", optional = true }
 
 [dev-dependencies]