diff --git a/Cargo.lock b/Cargo.lock
index a981255b6e68..cbfcb184faee 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1008,6 +1008,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c398b2b113b55809ceb9ee3e753fcbac793f1956663f3c36549c1346015c2afe"
 dependencies = [
  "autocfg 1.0.0",
+ "serde",
 ]
 
 [[package]]
diff --git a/cranelift/codegen/src/ir/extfunc.rs b/cranelift/codegen/src/ir/extfunc.rs
index 9bb089fd5606..6390f28a4353 100644
--- a/cranelift/codegen/src/ir/extfunc.rs
+++ b/cranelift/codegen/src/ir/extfunc.rs
@@ -11,6 +11,8 @@ use crate::machinst::RelocDistance;
 use alloc::vec::Vec;
 use core::fmt;
 use core::str::FromStr;
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
 
 /// Function signature.
 ///
@@ -20,6 +22,7 @@ use core::str::FromStr;
 /// A signature can optionally include ISA-specific ABI information which specifies exactly how
 /// arguments and return values are passed.
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct Signature {
     /// The arguments passed to the function.
     pub params: Vec<AbiParam>,
@@ -145,6 +148,7 @@ impl fmt::Display for Signature {
 /// This describes the value type being passed to or from a function along with flags that affect
 /// how the argument is passed.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct AbiParam {
     /// Type of the argument value.
     pub value_type: Type,
@@ -255,6 +259,7 @@ impl fmt::Display for AbiParam {
 /// On some architectures, small integer function arguments are extended to the width of a
 /// general-purpose register.
 #[derive(Copy, Clone, PartialEq, Eq, Debug, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub enum ArgumentExtension {
     /// No extension, high bits are indeterminate.
     None,
@@ -272,6 +277,7 @@ pub enum ArgumentExtension {
 ///
 /// The argument purpose is used to indicate any special meaning of an argument or return value.
 #[derive(Copy, Clone, PartialEq, Eq, Debug, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub enum ArgumentPurpose {
     /// A normal user program value passed to or from a function.
     Normal,
diff --git a/cranelift/codegen/src/ir/immediates.rs b/cranelift/codegen/src/ir/immediates.rs
index f6f485e4d103..27746315d68b 100644
--- a/cranelift/codegen/src/ir/immediates.rs
+++ b/cranelift/codegen/src/ir/immediates.rs
@@ -8,6 +8,8 @@ use alloc::vec::Vec;
 use core::fmt::{self, Display, Formatter};
 use core::str::FromStr;
 use core::{i32, u32};
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
 
 /// Convert a type into a vector of bytes; all implementors in this file must use little-endian
 /// orderings of bytes to match WebAssembly's little-endianness.
@@ -325,6 +327,7 @@ impl FromStr for Uimm32 {
 ///
 /// This is used as an immediate value in SIMD instructions.
 #[derive(Copy, Clone, PartialEq, Eq, Debug, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct V128Imm(pub [u8; 16]);
 
 impl V128Imm {
diff --git a/cranelift/codegen/src/ir/types.rs b/cranelift/codegen/src/ir/types.rs
index 060c087747b3..319f3ae66f69 100644
--- a/cranelift/codegen/src/ir/types.rs
+++ b/cranelift/codegen/src/ir/types.rs
@@ -3,6 +3,8 @@
 use core::default::Default;
 use core::fmt::{self, Debug, Display, Formatter};
 use cranelift_codegen_shared::constants;
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
 use target_lexicon::{PointerWidth, Triple};
 
 /// The type of an SSA value.
@@ -21,6 +23,7 @@ use target_lexicon::{PointerWidth, Triple};
 /// SIMD vector types have power-of-two lanes, up to 256. Lanes can be any int/float/bool type.
 ///
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct Type(u8);
 
 /// Not a valid type. Can't be loaded or stored. Can't be part of a SIMD vector.
diff --git a/cranelift/codegen/src/ir/valueloc.rs b/cranelift/codegen/src/ir/valueloc.rs
index 6fbe7e0195a1..d0b924886a19 100644
--- a/cranelift/codegen/src/ir/valueloc.rs
+++ b/cranelift/codegen/src/ir/valueloc.rs
@@ -98,6 +98,7 @@ impl<'a> fmt::Display for DisplayValueLoc<'a> {
 /// - For register arguments, there is usually no difference, but if we ever add support for a
 ///   register-window ISA like SPARC, register arguments would also need to be translated.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub enum ArgumentLoc {
     /// This argument has not been assigned to a location yet.
     Unassigned,
diff --git a/cranelift/wasm/src/code_translator.rs b/cranelift/wasm/src/code_translator.rs
index a0496677f0c5..800a793aab3f 100644
--- a/cranelift/wasm/src/code_translator.rs
+++ b/cranelift/wasm/src/code_translator.rs
@@ -30,6 +30,7 @@ use crate::translation_utils::{
 };
 use crate::translation_utils::{FuncIndex, GlobalIndex, MemoryIndex, SignatureIndex, TableIndex};
 use crate::wasm_unsupported;
+use core::convert::TryInto;
 use core::{i32, u32};
 use cranelift_codegen::ir::condcodes::{FloatCC, IntCC};
 use cranelift_codegen::ir::immediates::Offset32;
@@ -1039,7 +1040,9 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
         Operator::F32Le | Operator::F64Le => {
             translate_fcmp(FloatCC::LessThanOrEqual, builder, state)
         }
-        Operator::RefNull { ty } => state.push1(environ.translate_ref_null(builder.cursor(), *ty)?),
+        Operator::RefNull { ty } => {
+            state.push1(environ.translate_ref_null(builder.cursor(), (*ty).try_into()?)?)
+        }
         Operator::RefIsNull { ty: _ } => {
             let value = state.pop1();
             state.push1(environ.translate_ref_is_null(builder.cursor(), value)?);
diff --git a/cranelift/wasm/src/environ/dummy.rs b/cranelift/wasm/src/environ/dummy.rs
index 25f5c3a5929e..9047df05d27e 100644
--- a/cranelift/wasm/src/environ/dummy.rs
+++ b/cranelift/wasm/src/environ/dummy.rs
@@ -547,7 +547,7 @@ impl TargetEnvironment for DummyEnvironment {
 }
 
 impl<'data> ModuleEnvironment<'data> for DummyEnvironment {
-    fn declare_signature(&mut self, _wasm: &WasmFuncType, sig: ir::Signature) -> WasmResult<()> {
+    fn declare_signature(&mut self, _wasm: WasmFuncType, sig: ir::Signature) -> WasmResult<()> {
         self.info.signatures.push(sig);
         Ok(())
     }
diff --git a/cranelift/wasm/src/environ/spec.rs b/cranelift/wasm/src/environ/spec.rs
index eacc90233f33..9a3498b05eab 100644
--- a/cranelift/wasm/src/environ/spec.rs
+++ b/cranelift/wasm/src/environ/spec.rs
@@ -12,22 +12,89 @@ use crate::translation_utils::{
     Table, TableIndex,
 };
 use core::convert::From;
+use core::convert::TryFrom;
 use cranelift_codegen::cursor::FuncCursor;
 use cranelift_codegen::ir::immediates::Offset32;
 use cranelift_codegen::ir::{self, InstBuilder};
 use cranelift_codegen::isa::TargetFrontendConfig;
 use cranelift_frontend::FunctionBuilder;
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
 use std::boxed::Box;
+use std::string::ToString;
 use thiserror::Error;
 use wasmparser::BinaryReaderError;
 use wasmparser::Operator;
 
-// Re-export `wasmparser`'s function and value types so that consumers can
-// associate this the original Wasm signature with each compiled function. This
-// is often necessary because while each Wasm signature gets compiled down into
-// a single native signature, multiple Wasm signatures might compile down into
-// the same native signature.
-pub use wasmparser::{FuncType as WasmFuncType, Type as WasmType};
+/// WebAssembly value type -- equivalent of `wasmparser`'s Type.
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
+pub enum WasmType {
+    /// I32 type
+    I32,
+    /// I64 type
+    I64,
+    /// F32 type
+    F32,
+    /// F64 type
+    F64,
+    /// V128 type
+    V128,
+    /// FuncRef type
+    FuncRef,
+    /// ExternRef type
+    ExternRef,
+}
+
+impl TryFrom<wasmparser::Type> for WasmType {
+    type Error = WasmError;
+    fn try_from(ty: wasmparser::Type) -> Result<Self, Self::Error> {
+        use wasmparser::Type::*;
+        match ty {
+            I32 => Ok(WasmType::I32),
+            I64 => Ok(WasmType::I64),
+            F32 => Ok(WasmType::F32),
+            F64 => Ok(WasmType::F64),
+            V128 => Ok(WasmType::V128),
+            FuncRef => Ok(WasmType::FuncRef),
+            ExternRef => Ok(WasmType::ExternRef),
+            EmptyBlockType | Func => Err(WasmError::InvalidWebAssembly {
+                message: "unexpected value type".to_string(),
+                offset: 0,
+            }),
+        }
+    }
+}
+
+/// WebAssembly function type -- equivalent of `wasmparser`'s FuncType.
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
+pub struct WasmFuncType {
+    /// Function params types.
+    pub params: Box<[WasmType]>,
+    /// Returns params types.
+    pub returns: Box<[WasmType]>,
+}
+
+impl TryFrom<wasmparser::FuncType> for WasmFuncType {
+    type Error = WasmError;
+    fn try_from(ty: wasmparser::FuncType) -> Result<Self, Self::Error> {
+        Ok(Self {
+            params: ty
+                .params
+                .into_vec()
+                .into_iter()
+                .map(WasmType::try_from)
+                .collect::<Result<_, Self::Error>>()?,
+            returns: ty
+                .returns
+                .into_vec()
+                .into_iter()
+                .map(WasmType::try_from)
+                .collect::<Result<_, Self::Error>>()?,
+        })
+    }
+}
 
 /// The value of a WebAssembly global variable.
 #[derive(Clone, Copy)]
@@ -524,7 +591,7 @@ pub trait ModuleEnvironment<'data>: TargetEnvironment {
     /// Declares a function signature to the environment.
     fn declare_signature(
         &mut self,
-        wasm_func_type: &WasmFuncType,
+        wasm_func_type: WasmFuncType,
         sig: ir::Signature,
     ) -> WasmResult<()>;
 
diff --git a/cranelift/wasm/src/func_translator.rs b/cranelift/wasm/src/func_translator.rs
index 601996d6df11..11ec5b6ca72b 100644
--- a/cranelift/wasm/src/func_translator.rs
+++ b/cranelift/wasm/src/func_translator.rs
@@ -9,6 +9,7 @@ use crate::environ::{FuncEnvironment, ReturnMode, WasmResult};
 use crate::state::{FuncTranslationState, ModuleTranslationState};
 use crate::translation_utils::get_vmctx_value_label;
 use crate::wasm_unsupported;
+use core::convert::TryInto;
 use cranelift_codegen::entity::EntityRef;
 use cranelift_codegen::ir::{self, Block, InstBuilder, ValueLabel};
 use cranelift_codegen::timing;
@@ -196,7 +197,9 @@ fn declare_locals<FE: FuncEnvironment + ?Sized>(
             let constant_handle = builder.func.dfg.constants.insert([0; 16].to_vec().into());
             builder.ins().vconst(ir::types::I8X16, constant_handle)
         }
-        ExternRef | FuncRef => environ.translate_ref_null(builder.cursor(), wasm_type)?,
+        ExternRef | FuncRef => {
+            environ.translate_ref_null(builder.cursor(), wasm_type.try_into()?)?
+        }
         ty => return Err(wasm_unsupported!("unsupported local type {:?}", ty)),
     };
 
diff --git a/cranelift/wasm/src/sections_translator.rs b/cranelift/wasm/src/sections_translator.rs
index 7075fbc19bf8..36f93cda13ee 100644
--- a/cranelift/wasm/src/sections_translator.rs
+++ b/cranelift/wasm/src/sections_translator.rs
@@ -15,6 +15,7 @@ use crate::translation_utils::{
 };
 use crate::{wasm_unsupported, HashMap};
 use core::convert::TryFrom;
+use core::convert::TryInto;
 use cranelift_codegen::ir::immediates::V128Imm;
 use cranelift_codegen::ir::{self, AbiParam, Signature};
 use cranelift_entity::packed_option::ReservedValue;
@@ -53,7 +54,7 @@ pub fn parse_type_section(
                     .expect("only numeric types are supported in function signatures");
                 AbiParam::new(cret_arg)
             }));
-            environ.declare_signature(&wasm_func_ty, sig)?;
+            environ.declare_signature(wasm_func_ty.clone().try_into()?, sig)?;
             module_translation_state
                 .wasm_types
                 .push((wasm_func_ty.params, wasm_func_ty.returns));
@@ -104,7 +105,7 @@ pub fn parse_import_section<'data>(
             ImportSectionEntryType::Global(ref ty) => {
                 environ.declare_global_import(
                     Global {
-                        wasm_ty: ty.content_type,
+                        wasm_ty: ty.content_type.try_into()?,
                         ty: type_to_type(ty.content_type, environ).unwrap(),
                         mutability: ty.mutable,
                         initializer: GlobalInit::Import,
@@ -116,7 +117,7 @@ pub fn parse_import_section<'data>(
             ImportSectionEntryType::Table(ref tab) => {
                 environ.declare_table_import(
                     Table {
-                        wasm_ty: tab.element_type,
+                        wasm_ty: tab.element_type.try_into()?,
                         ty: match tabletype_to_type(tab.element_type, environ)? {
                             Some(t) => TableElementType::Val(t),
                             None => TableElementType::Func,
@@ -166,7 +167,7 @@ pub fn parse_table_section(
     for entry in tables {
         let table = entry?;
         environ.declare_table(Table {
-            wasm_ty: table.element_type,
+            wasm_ty: table.element_type.try_into()?,
             ty: match tabletype_to_type(table.element_type, environ)? {
                 Some(t) => TableElementType::Val(t),
                 None => TableElementType::Func,
@@ -237,7 +238,7 @@ pub fn parse_global_section(
             }
         };
         let global = Global {
-            wasm_ty: content_type,
+            wasm_ty: content_type.try_into()?,
             ty: type_to_type(content_type, environ).unwrap(),
             mutability: mutable,
             initializer,
diff --git a/cranelift/wasm/src/translation_utils.rs b/cranelift/wasm/src/translation_utils.rs
index 4bbab4e75ab4..2975584f7346 100644
--- a/cranelift/wasm/src/translation_utils.rs
+++ b/cranelift/wasm/src/translation_utils.rs
@@ -2,6 +2,7 @@
 use crate::environ::{TargetEnvironment, WasmResult, WasmType};
 use crate::state::ModuleTranslationState;
 use crate::wasm_unsupported;
+use core::convert::TryInto;
 use core::u32;
 use cranelift_codegen::entity::entity_impl;
 use cranelift_codegen::ir;
@@ -39,31 +40,37 @@ entity_impl!(DefinedGlobalIndex);
 
 /// Index type of a table (imported or defined) inside the WebAssembly module.
 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct TableIndex(u32);
 entity_impl!(TableIndex);
 
 /// Index type of a global variable (imported or defined) inside the WebAssembly module.
 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct GlobalIndex(u32);
 entity_impl!(GlobalIndex);
 
 /// Index type of a linear memory (imported or defined) inside the WebAssembly module.
 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct MemoryIndex(u32);
 entity_impl!(MemoryIndex);
 
 /// Index type of a signature (imported or defined) inside the WebAssembly module.
 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct SignatureIndex(u32);
 entity_impl!(SignatureIndex);
 
 /// Index type of a passive data segment inside the WebAssembly module.
 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct DataIndex(u32);
 entity_impl!(DataIndex);
 
 /// Index type of a passive element segment inside the WebAssembly module.
 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct ElemIndex(u32);
 entity_impl!(ElemIndex);
 
@@ -75,6 +82,7 @@ entity_impl!(ElemIndex);
 /// Wasm `i64` and a `funcref` might be represented with a Cranelift `i64` on
 /// 64-bit architectures, and when GC is not required for func refs.
 #[derive(Debug, Clone, Copy, Hash, Eq, PartialEq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct Global {
     /// The Wasm type of the value stored in the global.
     pub wasm_ty: crate::WasmType,
@@ -88,6 +96,7 @@ pub struct Global {
 
 /// Globals are initialized via the `const` operators or by referring to another import.
 #[derive(Debug, Clone, Copy, Hash, Eq, PartialEq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub enum GlobalInit {
     /// An `i32.const`.
     I32Const(i32),
@@ -111,6 +120,7 @@ pub enum GlobalInit {
 
 /// WebAssembly table.
 #[derive(Debug, Clone, Copy, Hash, Eq, PartialEq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct Table {
     /// The table elements' Wasm type.
     pub wasm_ty: WasmType,
@@ -124,6 +134,7 @@ pub struct Table {
 
 /// WebAssembly table element. Can be a function or a scalar type.
 #[derive(Debug, Clone, Copy, Hash, Eq, PartialEq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub enum TableElementType {
     /// A scalar type.
     Val(ir::Type),
@@ -133,6 +144,7 @@ pub enum TableElementType {
 
 /// WebAssembly linear memory.
 #[derive(Debug, Clone, Copy, Hash, Eq, PartialEq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct Memory {
     /// The minimum number of pages in the memory.
     pub minimum: u32,
@@ -153,7 +165,9 @@ pub fn type_to_type<PE: TargetEnvironment + ?Sized>(
         wasmparser::Type::F32 => Ok(ir::types::F32),
         wasmparser::Type::F64 => Ok(ir::types::F64),
         wasmparser::Type::V128 => Ok(ir::types::I8X16),
-        wasmparser::Type::ExternRef | wasmparser::Type::FuncRef => Ok(environ.reference_type(ty)),
+        wasmparser::Type::ExternRef | wasmparser::Type::FuncRef => {
+            Ok(environ.reference_type(ty.try_into()?))
+        }
         ty => Err(wasm_unsupported!("type_to_type: wasm type {:?}", ty)),
     }
 }
@@ -170,7 +184,7 @@ pub fn tabletype_to_type<PE: TargetEnvironment + ?Sized>(
         wasmparser::Type::F32 => Ok(Some(ir::types::F32)),
         wasmparser::Type::F64 => Ok(Some(ir::types::F64)),
         wasmparser::Type::V128 => Ok(Some(ir::types::I8X16)),
-        wasmparser::Type::ExternRef => Ok(Some(environ.reference_type(ty))),
+        wasmparser::Type::ExternRef => Ok(Some(environ.reference_type(ty.try_into()?))),
         wasmparser::Type::FuncRef => Ok(None),
         ty => Err(wasm_unsupported!(
             "tabletype_to_type: table wasm type {:?}",
@@ -226,7 +240,7 @@ pub fn block_with_params<PE: TargetEnvironment + ?Sized>(
                 builder.append_block_param(block, ir::types::F64);
             }
             wasmparser::Type::ExternRef | wasmparser::Type::FuncRef => {
-                builder.append_block_param(block, environ.reference_type(*ty));
+                builder.append_block_param(block, environ.reference_type((*ty).try_into()?));
             }
             wasmparser::Type::V128 => {
                 builder.append_block_param(block, ir::types::I8X16);
diff --git a/crates/environ/Cargo.toml b/crates/environ/Cargo.toml
index 1ab3dd6d07d0..73ddf7a2aef1 100644
--- a/crates/environ/Cargo.toml
+++ b/crates/environ/Cargo.toml
@@ -19,7 +19,7 @@ cranelift-frontend = { path = "../../cranelift/frontend", version = "0.65.0" }
 cranelift-wasm = { path = "../../cranelift/wasm", version = "0.65.0", features = ["enable-serde"] }
 wasmparser = "0.58.0"
 lightbeam = { path = "../lightbeam", optional = true, version = "0.18.0" }
-indexmap = "1.0.2"
+indexmap = { version = "1.0.2", features = ["serde-1"] }
 rayon = { version = "1.2.1", optional = true }
 thiserror = "1.0.4"
 directories = "2.0.1"
diff --git a/crates/environ/src/module.rs b/crates/environ/src/module.rs
index 280210cfa4f0..2f9348fe40fe 100644
--- a/crates/environ/src/module.rs
+++ b/crates/environ/src/module.rs
@@ -11,6 +11,7 @@ use cranelift_wasm::{
 };
 use indexmap::IndexMap;
 use more_asserts::assert_ge;
+use serde::{Deserialize, Serialize};
 use std::collections::HashMap;
 use std::sync::{
     atomic::{AtomicUsize, Ordering::SeqCst},
@@ -18,7 +19,7 @@ use std::sync::{
 };
 
 /// A WebAssembly table initializer.
-#[derive(Clone, Debug, Hash)]
+#[derive(Clone, Debug, Hash, Serialize, Deserialize)]
 pub struct TableElements {
     /// The index of a table to initialize.
     pub table_index: TableIndex,
@@ -31,7 +32,7 @@ pub struct TableElements {
 }
 
 /// An index of an entity.
-#[derive(Clone, Debug, Hash, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Clone, Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Serialize, Deserialize)]
 pub enum EntityIndex {
     /// Function index.
     Function(FuncIndex),
@@ -44,7 +45,7 @@ pub enum EntityIndex {
 }
 
 /// Implemenation styles for WebAssembly linear memory.
-#[derive(Debug, Clone, Hash)]
+#[derive(Debug, Clone, Hash, Serialize, Deserialize)]
 pub enum MemoryStyle {
     /// The actual memory can be resized and moved.
     Dynamic,
@@ -80,7 +81,7 @@ impl MemoryStyle {
 
 /// A WebAssembly linear memory description along with our chosen style for
 /// implementing it.
-#[derive(Debug, Clone, Hash)]
+#[derive(Debug, Clone, Hash, Serialize, Deserialize)]
 pub struct MemoryPlan {
     /// The WebAssembly linear memory description.
     pub memory: Memory,
@@ -103,7 +104,7 @@ impl MemoryPlan {
 }
 
 /// Implemenation styles for WebAssembly tables.
-#[derive(Debug, Clone, Hash)]
+#[derive(Debug, Clone, Hash, Serialize, Deserialize)]
 pub enum TableStyle {
     /// Signatures are stored in the table and checked in the caller.
     CallerChecksSignature,
@@ -118,7 +119,7 @@ impl TableStyle {
 
 /// A WebAssembly table description along with our chosen style for
 /// implementing it.
-#[derive(Debug, Clone, Hash)]
+#[derive(Debug, Clone, Hash, Serialize, Deserialize)]
 pub struct TablePlan {
     /// The WebAssembly table description.
     pub table: cranelift_wasm::Table,
@@ -136,9 +137,10 @@ impl TablePlan {
 
 /// A translated WebAssembly module, excluding the function bodies and
 /// memory initializers.
-#[derive(Debug)]
+#[derive(Debug, Serialize, Deserialize)]
 pub struct Module {
     /// A unique identifier (within this process) for this module.
+    #[serde(skip_serializing, default = "Module::next_id")]
     pub id: usize,
 
     /// The name of this wasm module, often found in the wasm file.
@@ -166,6 +168,7 @@ pub struct Module {
     pub passive_elements: HashMap<ElemIndex, Box<[FuncIndex]>>,
 
     /// WebAssembly passive data segments.
+    #[serde(with = "passive_data_serde")]
     pub passive_data: HashMap<DataIndex, Arc<[u8]>>,
 
     /// WebAssembly table initializers.
@@ -178,7 +181,7 @@ pub struct Module {
 /// This is stored within a `Module` and it implements `Hash`, unlike `Module`,
 /// and is used as part of the cache key when we load compiled modules from the
 /// global cache.
-#[derive(Debug, Hash)]
+#[derive(Debug, Hash, Serialize, Deserialize)]
 pub struct ModuleLocal {
     /// Unprocessed signatures exactly as provided by `declare_signature()`.
     pub signatures: PrimaryMap<SignatureIndex, (WasmFuncType, ir::Signature)>,
@@ -211,10 +214,8 @@ pub struct ModuleLocal {
 impl Module {
     /// Allocates the module data structures.
     pub fn new() -> Self {
-        static NEXT_ID: AtomicUsize = AtomicUsize::new(0);
-
         Self {
-            id: NEXT_ID.fetch_add(1, SeqCst),
+            id: Self::next_id(),
             name: None,
             imports: Vec::new(),
             exports: IndexMap::new(),
@@ -241,6 +242,11 @@ impl Module {
     pub fn get_passive_element(&self, index: ElemIndex) -> Option<&[FuncIndex]> {
         self.passive_elements.get(&index).map(|es| &**es)
     }
+
+    fn next_id() -> usize {
+        static NEXT_ID: AtomicUsize = AtomicUsize::new(0);
+        NEXT_ID.fetch_add(1, SeqCst)
+    }
 }
 
 impl ModuleLocal {
@@ -344,3 +350,49 @@ impl ModuleLocal {
         &self.signatures[self.functions[func_index]].0
     }
 }
+
+mod passive_data_serde {
+    use super::{Arc, DataIndex, HashMap};
+    use serde::{de::MapAccess, de::Visitor, ser::SerializeMap, Deserializer, Serializer};
+    use std::fmt;
+
+    pub(super) fn serialize<S>(
+        data: &HashMap<DataIndex, Arc<[u8]>>,
+        ser: S,
+    ) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let mut map = ser.serialize_map(Some(data.len()))?;
+        for (k, v) in data {
+            map.serialize_entry(k, v.as_ref())?;
+        }
+        map.end()
+    }
+
+    struct PassiveDataVisitor;
+    impl<'de> Visitor<'de> for PassiveDataVisitor {
+        type Value = HashMap<DataIndex, Arc<[u8]>>;
+
+        fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+            formatter.write_str("a passive_data map")
+        }
+        fn visit_map<M>(self, mut access: M) -> Result<Self::Value, M::Error>
+        where
+            M: MapAccess<'de>,
+        {
+            let mut map = HashMap::with_capacity(access.size_hint().unwrap_or(0));
+            while let Some((key, value)) = access.next_entry::<_, Vec<u8>>()? {
+                map.insert(key, value.into());
+            }
+            Ok(map)
+        }
+    }
+
+    pub(super) fn deserialize<'de, D>(de: D) -> Result<HashMap<DataIndex, Arc<[u8]>>, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        de.deserialize_map(PassiveDataVisitor)
+    }
+}
diff --git a/crates/environ/src/module_environ.rs b/crates/environ/src/module_environ.rs
index 8d6cd7997f78..1c363dcff49a 100644
--- a/crates/environ/src/module_environ.rs
+++ b/crates/environ/src/module_environ.rs
@@ -110,14 +110,10 @@ impl<'data> cranelift_wasm::ModuleEnvironment<'data> for ModuleEnvironment<'data
         Ok(())
     }
 
-    fn declare_signature(&mut self, wasm: &WasmFuncType, sig: ir::Signature) -> WasmResult<()> {
+    fn declare_signature(&mut self, wasm: WasmFuncType, sig: ir::Signature) -> WasmResult<()> {
         let sig = translate_signature(sig, self.pointer_type());
         // TODO: Deduplicate signatures.
-        self.result
-            .module
-            .local
-            .signatures
-            .push((wasm.clone(), sig));
+        self.result.module.local.signatures.push((wasm, sig));
         Ok(())
     }
 
diff --git a/crates/wasmtime/src/externals.rs b/crates/wasmtime/src/externals.rs
index 3beec44cf90f..ad25a6370d5b 100644
--- a/crates/wasmtime/src/externals.rs
+++ b/crates/wasmtime/src/externals.rs
@@ -202,13 +202,11 @@ impl Global {
         // The original export is coming from wasmtime_runtime itself we should
         // support all the types coming out of it, so assert such here.
         GlobalType::from_wasmtime_global(&self.wasmtime_export.global)
-            .expect("core wasm global type should be supported")
     }
 
     /// Returns the value type of this `global`.
     pub fn val_type(&self) -> ValType {
         ValType::from_wasm_type(&self.wasmtime_export.global.wasm_ty)
-            .expect("core wasm type should be supported")
     }
 
     /// Returns the underlying mutability of this `global`.
diff --git a/crates/wasmtime/src/func.rs b/crates/wasmtime/src/func.rs
index 660a9e84a233..749f632c09f2 100644
--- a/crates/wasmtime/src/func.rs
+++ b/crates/wasmtime/src/func.rs
@@ -545,7 +545,7 @@ impl Func {
         // This is only called with `Export::Function`, and since it's coming
         // from wasmtime_runtime itself we should support all the types coming
         // out of it, so assert such here.
-        FuncType::from_wasm_func_type(&wft).expect("core wasm signature should be supported")
+        FuncType::from_wasm_func_type(&wft)
     }
 
     /// Returns the number of parameters that this function takes.
diff --git a/crates/wasmtime/src/types.rs b/crates/wasmtime/src/types.rs
index 3baf77d5cbec..877562e1f995 100644
--- a/crates/wasmtime/src/types.rs
+++ b/crates/wasmtime/src/types.rs
@@ -123,16 +123,15 @@ impl ValType {
         }
     }
 
-    pub(crate) fn from_wasm_type(ty: &wasm::WasmType) -> Option<Self> {
+    pub(crate) fn from_wasm_type(ty: &wasm::WasmType) -> Self {
         match ty {
-            wasm::WasmType::I32 => Some(Self::I32),
-            wasm::WasmType::I64 => Some(Self::I64),
-            wasm::WasmType::F32 => Some(Self::F32),
-            wasm::WasmType::F64 => Some(Self::F64),
-            wasm::WasmType::V128 => Some(Self::V128),
-            wasm::WasmType::FuncRef => Some(Self::FuncRef),
-            wasm::WasmType::ExternRef => Some(Self::ExternRef),
-            wasm::WasmType::Func | wasm::WasmType::EmptyBlockType => None,
+            wasm::WasmType::I32 => Self::I32,
+            wasm::WasmType::I64 => Self::I64,
+            wasm::WasmType::F32 => Self::F32,
+            wasm::WasmType::F64 => Self::F64,
+            wasm::WasmType::V128 => Self::V128,
+            wasm::WasmType::FuncRef => Self::FuncRef,
+            wasm::WasmType::ExternRef => Self::ExternRef,
         }
     }
 }
@@ -279,21 +278,21 @@ impl FuncType {
     /// Returns `None` if any types in the signature can't be converted to the
     /// types in this crate, but that should very rarely happen and largely only
     /// indicate a bug in our cranelift integration.
-    pub(crate) fn from_wasm_func_type(signature: &wasm::WasmFuncType) -> Option<FuncType> {
+    pub(crate) fn from_wasm_func_type(signature: &wasm::WasmFuncType) -> FuncType {
         let params = signature
             .params
             .iter()
             .map(|p| ValType::from_wasm_type(p))
-            .collect::<Option<Vec<_>>>()?;
+            .collect::<Vec<_>>();
         let results = signature
             .returns
             .iter()
             .map(|r| ValType::from_wasm_type(r))
-            .collect::<Option<Vec<_>>>()?;
-        Some(FuncType {
+            .collect::<Vec<_>>();
+        FuncType {
             params: params.into_boxed_slice(),
             results: results.into_boxed_slice(),
-        })
+        }
     }
 }
 
@@ -332,14 +331,14 @@ impl GlobalType {
 
     /// Returns `None` if the wasmtime global has a type that we can't
     /// represent, but that should only very rarely happen and indicate a bug.
-    pub(crate) fn from_wasmtime_global(global: &wasm::Global) -> Option<GlobalType> {
-        let ty = ValType::from_wasm_type(&global.wasm_ty)?;
+    pub(crate) fn from_wasmtime_global(global: &wasm::Global) -> GlobalType {
+        let ty = ValType::from_wasm_type(&global.wasm_ty);
         let mutability = if global.mutability {
             Mutability::Var
         } else {
             Mutability::Const
         };
-        Some(GlobalType::new(ty, mutability))
+        GlobalType::new(ty, mutability)
     }
 }
 
@@ -451,14 +450,10 @@ impl<'module> EntityType<'module> {
     /// Convert this `EntityType` to an `ExternType`.
     pub(crate) fn extern_type(&self) -> ExternType {
         match self {
-            EntityType::Function(sig) => FuncType::from_wasm_func_type(sig)
-                .expect("core wasm function type should be supported")
-                .into(),
+            EntityType::Function(sig) => FuncType::from_wasm_func_type(sig).into(),
             EntityType::Table(table) => TableType::from_wasmtime_table(table).into(),
             EntityType::Memory(memory) => MemoryType::from_wasmtime_memory(memory).into(),
-            EntityType::Global(global) => GlobalType::from_wasmtime_global(global)
-                .expect("core wasm global type should be supported")
-                .into(),
+            EntityType::Global(global) => GlobalType::from_wasmtime_global(global).into(),
         }
     }
 }