diff --git a/src/builder/code.rs b/src/builder/code.rs
index e86d53e..3614f7a 100644
--- a/src/builder/code.rs
+++ b/src/builder/code.rs
@@ -255,8 +255,11 @@ impl<F> FuncBodyBuilder<F> where F: Invoke<elements::FuncBody> {
 
 /// Function definition (extended structure to specify function entirely, incl. signature, mainness and code)
 pub struct FunctionDefinition {
+    /// Is this function is start function
     pub is_main: bool,
+    /// Signature description
     pub signature: Signature,
+    /// Body (code) of the function
     pub code: elements::FuncBody,
 }
 
diff --git a/src/builder/export.rs b/src/builder/export.rs
index 837043c..9016441 100644
--- a/src/builder/export.rs
+++ b/src/builder/export.rs
@@ -9,6 +9,7 @@ pub struct ExportBuilder<F=Identity> {
 }
 
 impl ExportBuilder {
+    /// New export builder
     pub fn new() -> Self {
         ExportBuilder::with_callback(Identity)
     }
diff --git a/src/builder/global.rs b/src/builder/global.rs
index 9c666f3..326572c 100644
--- a/src/builder/global.rs
+++ b/src/builder/global.rs
@@ -2,6 +2,7 @@ use super::invoke::{Invoke, Identity};
 use super::misc::ValueTypeBuilder;
 use elements;
 
+/// Global builder
 pub struct GlobalBuilder<F=Identity> {
     callback: F,
     value_type: elements::ValueType,
@@ -10,12 +11,14 @@ pub struct GlobalBuilder<F=Identity> {
 }
 
 impl GlobalBuilder {
+    /// New global builder
     pub fn new() -> Self {
         GlobalBuilder::with_callback(Identity)
     }
 }
 
 impl<F> GlobalBuilder<F> {
+    /// New global builder with callback (in chained context)
     pub fn with_callback(callback: F) -> Self {
         GlobalBuilder {
             callback: callback,
@@ -25,31 +28,36 @@ impl<F> GlobalBuilder<F> {
         }
     }
 
+    /// Set/override resulting global type
     pub fn with_type(mut self, value_type: elements::ValueType) -> Self {
         self.value_type = value_type;
         self
     }
 
+    /// Set mutabilty to true
     pub fn mutable(mut self) -> Self {
         self.is_mutable = true;
         self
     }
 
+    /// Set initialization expression opcode for this global (`end` opcode will be added automatically)
     pub fn init_expr(mut self, opcode: elements::Opcode) -> Self {
         self.init_expr = elements::InitExpr::new(vec![opcode, elements::Opcode::End]);
         self
     }
 
+    /// Start value type builder
     pub fn value_type(self) -> ValueTypeBuilder<Self> {
         ValueTypeBuilder::with_callback(self)
     }
 }
 
 impl<F> GlobalBuilder<F> where F: Invoke<elements::GlobalEntry> {
+    /// Finalize current builder spawning resulting struct
     pub fn build(self) -> F::Result {
         self.callback.invoke(
             elements::GlobalEntry::new(
-                elements::GlobalType::new(self.value_type, self.is_mutable), 
+                elements::GlobalType::new(self.value_type, self.is_mutable),
                 self.init_expr,
             )
         )
diff --git a/src/builder/import.rs b/src/builder/import.rs
index 4297115..77d51f4 100644
--- a/src/builder/import.rs
+++ b/src/builder/import.rs
@@ -1,6 +1,7 @@
 use super::invoke::{Invoke, Identity};
 use elements;
 
+/// Import builder
 pub struct ImportBuilder<F=Identity> {
     callback: F,
     module: String,
@@ -9,13 +10,14 @@ pub struct ImportBuilder<F=Identity> {
 }
 
 impl ImportBuilder {
+    /// New import builder
     pub fn new() -> Self {
         ImportBuilder::with_callback(Identity)
     }
 }
 
 impl<F> ImportBuilder<F> {
-
+    /// New import builder with callback (in chained context)
     pub fn with_callback(callback: F) -> Self {
         ImportBuilder {
             callback: callback,
@@ -25,31 +27,37 @@ impl<F> ImportBuilder<F> {
         }
     }
 
+    /// Set/override module name
     pub fn module(mut self, name: &str) -> Self {
         self.module = name.to_owned();
         self
     }
 
+    /// Set/override field name
     pub fn field(mut self, name: &str) -> Self {
         self.field = name.to_owned();
         self
     }
 
+    /// Set/override both module name and field name
     pub fn path(self, module: &str, field: &str) -> Self {
         self.module(module).field(field)
     }
 
+    /// Set/override external mapping for this import
     pub fn with_external(mut self, external: elements::External) -> Self {
         self.binding = external;
         self
     }
 
+    /// Start new external mapping builder
     pub fn external(self) -> ImportExternalBuilder<Self> {
         ImportExternalBuilder::with_callback(self)
     }
 }
 
 impl<F> ImportBuilder<F> where F: Invoke<elements::ImportEntry> {
+    /// Finalize current builder spawning the resulting struct
     pub fn build(self) -> F::Result {
         self.callback.invoke(elements::ImportEntry::new(self.module, self.field, self.binding))
     }
@@ -62,12 +70,14 @@ impl<F> Invoke<elements::External> for ImportBuilder<F> {
     }
 }
 
+/// Import to external mapping builder
 pub struct ImportExternalBuilder<F=Identity> {
     callback: F,
     binding: elements::External,
 }
 
 impl<F> ImportExternalBuilder<F> where F: Invoke<elements::External> {
+    /// New import to external mapping builder with callback (in chained context)
     pub fn with_callback(callback: F) -> Self {
         ImportExternalBuilder{
             callback: callback,
@@ -75,21 +85,25 @@ impl<F> ImportExternalBuilder<F> where F: Invoke<elements::External> {
         }
     }
 
+    /// Function mapping with type reference
     pub fn func(mut self, index: u32) -> F::Result {
         self.binding = elements::External::Function(index);
         self.callback.invoke(self.binding)
     }
 
+    /// Memory mapping with specified limits
     pub fn memory(mut self, min: u32, max: Option<u32>) -> F::Result {
         self.binding = elements::External::Memory(elements::MemoryType::new(min, max));
         self.callback.invoke(self.binding)
     }
 
+    /// Table mapping with specified limits
     pub fn table(mut self, min: u32, max: Option<u32>) -> F::Result {
         self.binding = elements::External::Table(elements::TableType::new(min, max));
         self.callback.invoke(self.binding)
     }
 
+    /// Global mapping with speciifed type and mutability
     pub fn global(mut self, value_type: elements::ValueType, is_mut: bool) -> F::Result {
         self.binding = elements::External::Global(elements::GlobalType::new(value_type, is_mut));
         self.callback.invoke(self.binding)
diff --git a/src/builder/memory.rs b/src/builder/memory.rs
index aed5473..c6fd0b0 100644
--- a/src/builder/memory.rs
+++ b/src/builder/memory.rs
@@ -1,31 +1,41 @@
 use elements;
 use super::invoke::{Invoke, Identity};
 
+/// Memory definition struct
 #[derive(Debug)]
 pub struct MemoryDefinition {
+    /// Minimum memory size
     pub min: u32,
+    /// Maximum memory size
     pub max: Option<u32>,
+    /// Memory data segments (static regions)
     pub data: Vec<MemoryDataDefinition>,
 }
 
+/// Memory static region entry definition
 #[derive(Debug)]
 pub struct MemoryDataDefinition {
+    /// Segment initialization expression for offset
     pub offset: elements::InitExpr,
+    /// Raw bytes of static region
     pub values: Vec<u8>,
 }
 
+/// Memory and static regions builder
 pub struct MemoryBuilder<F=Identity> {
     callback: F,
     memory: MemoryDefinition,
 }
 
 impl MemoryBuilder {
+    /// New memory builder
     pub fn new() -> Self {
         MemoryBuilder::with_callback(Identity)
     }
 }
 
 impl<F> MemoryBuilder<F> where F: Invoke<MemoryDefinition> {
+    /// New memory builder with callback (in chained context)
     pub fn with_callback(callback: F) -> Self {
         MemoryBuilder {
             callback: callback,
@@ -33,16 +43,19 @@ impl<F> MemoryBuilder<F> where F: Invoke<MemoryDefinition> {
         }
     }
 
+    /// Set/override minimum size
     pub fn with_min(mut self, min: u32) -> Self {
         self.memory.min = min;
         self
     }
 
+    /// Set/override maximum size
     pub fn with_max(mut self, max: Option<u32>) -> Self {
         self.memory.max = max;
         self
     }
 
+    /// Push new static region with initialized offset expression and raw bytes
     pub fn with_data(mut self, index: u32, values: Vec<u8>) -> Self {
         self.memory.data.push(MemoryDataDefinition {
             offset: elements::InitExpr::new(vec![
@@ -54,6 +67,7 @@ impl<F> MemoryBuilder<F> where F: Invoke<MemoryDefinition> {
         self
     }
 
+    /// Finalize current builder, spawning resulting struct
     pub fn build(self) -> F::Result {
         self.callback.invoke(self.memory)
     }
diff --git a/src/builder/table.rs b/src/builder/table.rs
index 3706870..e5e35b6 100644
--- a/src/builder/table.rs
+++ b/src/builder/table.rs
@@ -1,31 +1,41 @@
 use elements;
 use super::invoke::{Invoke, Identity};
 
+/// Table definition
 #[derive(Debug)]
 pub struct TableDefinition {
+    /// Minimum length
     pub min: u32,
+    /// Maximum length, if any
     pub max: Option<u32>,
+    /// Element segments, if any
     pub elements: Vec<TableEntryDefinition>,
 }
 
+/// Table elements entry definition
 #[derive(Debug)]
 pub struct TableEntryDefinition {
+    /// Offset initialization expression
     pub offset: elements::InitExpr,
+    /// Values of initialization
     pub values: Vec<u32>,
 }
 
+/// Table builder
 pub struct TableBuilder<F=Identity> {
     callback: F,
     table: TableDefinition,
 }
 
 impl TableBuilder {
+    /// New table builder
     pub fn new() -> Self {
         TableBuilder::with_callback(Identity)
     }
 }
 
 impl<F> TableBuilder<F> where F: Invoke<TableDefinition> {
+    /// New table builder with callback in chained context
     pub fn with_callback(callback: F) -> Self {
         TableBuilder {
             callback: callback,
@@ -33,16 +43,19 @@ impl<F> TableBuilder<F> where F: Invoke<TableDefinition> {
         }
     }
 
+    /// Set/override minimum length
     pub fn with_min(mut self, min: u32) -> Self {
         self.table.min = min;
         self
     }
 
+    /// Set/override maximum length
     pub fn with_max(mut self, max: Option<u32>) -> Self {
         self.table.max = max;
         self
     }
 
+    /// Generate initialization expression and element values on specified index
     pub fn with_element(mut self, index: u32, values: Vec<u32>) -> Self {
         self.table.elements.push(TableEntryDefinition {
             offset: elements::InitExpr::new(vec![
@@ -54,6 +67,7 @@ impl<F> TableBuilder<F> where F: Invoke<TableDefinition> {
         self
     }
 
+    /// Finalize current builder spawning resulting struct
     pub fn build(self) -> F::Result {
         self.callback.invoke(self.table)
     }