diff --git a/bshell/ast/array.c b/bshell/ast/array.c
new file mode 100644
index 0000000..7eaa59e
--- /dev/null
+++ b/bshell/ast/array.c
@@ -0,0 +1,25 @@
+#include "../parse/token.h"
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct array_ast_node *array = (struct array_ast_node *)node;
+
+	fx_queue_entry *cur = fx_queue_first(&array->n_items);
+	while (cur) {
+		struct ast_node *child
+			= fx_unbox(struct ast_node, cur, n_entry);
+		ast_iterator_enqueue(it, child);
+		cur = fx_queue_next(cur);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+struct ast_node_definition array_ast_node = {
+	.def_id = AST_ARRAY,
+	.def_node_size = sizeof(struct array_ast_node),
+	.def_collect_children = collect_children,
+};
diff --git a/bshell/ast/ast.c b/bshell/ast/ast.c
index 668b6b3..32aef93 100644
--- a/bshell/ast/ast.c
+++ b/bshell/ast/ast.c
@@ -6,6 +6,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+extern struct ast_node_definition null_ast_node;
 extern struct ast_node_definition int_ast_node;
 extern struct ast_node_definition double_ast_node;
 extern struct ast_node_definition word_ast_node;
@@ -15,8 +16,18 @@ extern struct ast_node_definition fstring_ast_node;
 extern struct ast_node_definition cmdcall_ast_node;
 extern struct ast_node_definition pipeline_ast_node;
 extern struct ast_node_definition redirection_ast_node;
+extern struct ast_node_definition block_ast_node;
+extern struct ast_node_definition stmt_list_ast_node;
+extern struct ast_node_definition func_ast_node;
+extern struct ast_node_definition array_ast_node;
+extern struct ast_node_definition hashtable_ast_node;
+extern struct ast_node_definition hashtable_item_ast_node;
+extern struct ast_node_definition if_ast_node;
+extern struct ast_node_definition if_branch_ast_node;
+extern struct ast_node_definition op_ast_node;
 
 static const struct ast_node_definition *ast_node_defintions[] = {
+	[AST_NULL] = &null_ast_node,
 	[AST_INT] = &int_ast_node,
 	[AST_DOUBLE] = &double_ast_node,
 	[AST_WORD] = &word_ast_node,
@@ -26,6 +37,15 @@ static const struct ast_node_definition *ast_node_defintions[] = {
 	[AST_CMDCALL] = &cmdcall_ast_node,
 	[AST_PIPELINE] = &pipeline_ast_node,
 	[AST_REDIRECTION] = &redirection_ast_node,
+	[AST_BLOCK] = &block_ast_node,
+	[AST_STMT_LIST] = &stmt_list_ast_node,
+	[AST_FUNC] = &func_ast_node,
+	[AST_ARRAY] = &array_ast_node,
+	[AST_IF] = &if_ast_node,
+	[AST_IF_BRANCH] = &if_branch_ast_node,
+	[AST_HASHTABLE] = &hashtable_ast_node,
+	[AST_HASHTABLE_ITEM] = &hashtable_item_ast_node,
+	[AST_OP] = &op_ast_node,
 };
 static const size_t nr_ast_node_definitions
 	= sizeof ast_node_defintions / sizeof ast_node_defintions[0];
@@ -94,6 +114,8 @@ const char *ast_node_type_to_string(enum ast_node_type type)
 {
 	switch (type) {
 		ENUM_STR(AST_NONE);
+		ENUM_STR(AST_NULL);
+		ENUM_STR(AST_STMT_LIST);
 		ENUM_STR(AST_INT);
 		ENUM_STR(AST_DOUBLE);
 		ENUM_STR(AST_WORD);
@@ -105,6 +127,14 @@ const char *ast_node_type_to_string(enum ast_node_type type)
 		ENUM_STR(AST_CMDCALL);
 		ENUM_STR(AST_PIPELINE);
 		ENUM_STR(AST_REDIRECTION);
+		ENUM_STR(AST_BLOCK);
+		ENUM_STR(AST_FUNC);
+		ENUM_STR(AST_IF);
+		ENUM_STR(AST_IF_BRANCH);
+		ENUM_STR(AST_OP);
+		ENUM_STR(AST_ARRAY);
+		ENUM_STR(AST_HASHTABLE);
+		ENUM_STR(AST_HASHTABLE_ITEM);
 	default:
 		return "<unknown>";
 	}
diff --git a/bshell/ast/ast.h b/bshell/ast/ast.h
index 5cc2d44..826cb3c 100644
--- a/bshell/ast/ast.h
+++ b/bshell/ast/ast.h
@@ -10,6 +10,8 @@ struct lex_token;
 
 enum ast_node_type {
 	AST_NONE = 0x00u,
+	AST_NULL,
+	AST_STMT_LIST,
 	AST_INT,
 	AST_DOUBLE,
 	AST_WORD,
@@ -19,8 +21,17 @@ enum ast_node_type {
 	AST_VAR_SPLAT,
 	AST_FLAG,
 	AST_CMDCALL,
+	AST_FUNCALL,
 	AST_PIPELINE,
 	AST_REDIRECTION,
+	AST_BLOCK,
+	AST_FUNC,
+	AST_ARRAY,
+	AST_HASHTABLE,
+	AST_HASHTABLE_ITEM,
+	AST_OP,
+	AST_IF,
+	AST_IF_BRANCH,
 };
 
 struct ast_iterator_entry {
@@ -35,6 +46,10 @@ struct ast_node {
 	struct ast_iterator_entry n_it;
 };
 
+struct null_ast_node {
+	struct ast_node n_base;
+};
+
 struct int_ast_node {
 	struct ast_node n_base;
 	struct lex_token *n_value;
@@ -76,6 +91,12 @@ struct cmdcall_ast_node {
 	fx_queue n_redirect;
 };
 
+struct funcall_ast_node {
+	struct ast_node n_base;
+	struct ast_node *n_func;
+	fx_queue n_args;
+};
+
 struct pipeline_ast_node {
 	struct ast_node n_base;
 	fx_queue n_stages;
@@ -93,6 +114,55 @@ struct redirection_ast_node {
 	struct lex_token *n_out_tok;
 };
 
+struct stmt_list_ast_node {
+	struct ast_node n_base;
+	fx_queue n_statements;
+};
+
+struct block_ast_node {
+	struct ast_node n_base;
+	fx_queue n_statements;
+};
+
+struct func_ast_node {
+	struct ast_node n_base;
+	struct lex_token *n_name;
+	fx_queue n_params;
+	struct ast_node *n_body;
+};
+
+struct array_ast_node {
+	struct ast_node n_base;
+	fx_queue n_items;
+};
+
+struct hashtable_ast_node {
+	struct ast_node n_base;
+	fx_queue n_items;
+};
+
+struct hashtable_item_ast_node {
+	struct ast_node n_base;
+	struct ast_node *n_key, *n_value;
+};
+
+struct op_ast_node {
+	struct ast_node n_base;
+	const struct operator_info *n_op;
+	struct ast_node *n_left, *n_right;
+};
+
+struct if_branch_ast_node {
+	struct ast_node n_base;
+	struct ast_node *n_cond;
+	struct ast_node *n_body;
+};
+
+struct if_ast_node {
+	struct ast_node n_base;
+	fx_queue n_branches;
+};
+
 struct ast_iterator {
 	struct ast_node *it_cur;
 	fx_queue it_queue;
diff --git a/bshell/ast/block.c b/bshell/ast/block.c
new file mode 100644
index 0000000..90681e3
--- /dev/null
+++ b/bshell/ast/block.c
@@ -0,0 +1,23 @@
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct block_ast_node *block = (struct block_ast_node *)node;
+	fx_queue_entry *cur = fx_queue_first(&block->n_statements);
+	while (cur) {
+		struct ast_node *child
+			= fx_unbox(struct ast_node, cur, n_entry);
+		ast_iterator_enqueue(it, child);
+		cur = fx_queue_next(cur);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+struct ast_node_definition block_ast_node = {
+	.def_id = AST_BLOCK,
+	.def_node_size = sizeof(struct block_ast_node),
+	.def_collect_children = collect_children,
+};
diff --git a/bshell/ast/fstring.c b/bshell/ast/fstring.c
index 687436f..894ba18 100644
--- a/bshell/ast/fstring.c
+++ b/bshell/ast/fstring.c
@@ -1,6 +1,23 @@
 #include "ast.h"
 
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct fstring_ast_node *fstring = (struct fstring_ast_node *)node;
+	fx_queue_entry *cur = fx_queue_first(&fstring->n_elements);
+	while (cur) {
+		struct ast_node *child
+			= fx_unbox(struct ast_node, cur, n_entry);
+		ast_iterator_enqueue(it, child);
+		cur = fx_queue_next(cur);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
 struct ast_node_definition fstring_ast_node = {
 	.def_id = AST_FSTRING,
 	.def_node_size = sizeof(struct fstring_ast_node),
+	.def_collect_children = collect_children,
 };
diff --git a/bshell/ast/func.c b/bshell/ast/func.c
new file mode 100644
index 0000000..61c53a6
--- /dev/null
+++ b/bshell/ast/func.c
@@ -0,0 +1,36 @@
+#include "../parse/token.h"
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct func_ast_node *func = (struct func_ast_node *)node;
+
+	fx_queue_entry *cur = fx_queue_first(&func->n_params);
+	while (cur) {
+		struct ast_node *child
+			= fx_unbox(struct ast_node, cur, n_entry);
+		ast_iterator_enqueue(it, child);
+		cur = fx_queue_next(cur);
+	}
+
+	if (func->n_body) {
+		ast_iterator_enqueue(it, func->n_body);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+static void to_string(const struct ast_node *node, fx_bstr *out)
+{
+	const struct func_ast_node *func = (const struct func_ast_node *)node;
+	fx_bstr_write_fmt(out, NULL, "%s", func->n_name->tok_str);
+}
+
+struct ast_node_definition func_ast_node = {
+	.def_id = AST_FUNC,
+	.def_node_size = sizeof(struct func_ast_node),
+	.def_collect_children = collect_children,
+	.def_to_string = to_string,
+};
diff --git a/bshell/ast/hashtable-item.c b/bshell/ast/hashtable-item.c
new file mode 100644
index 0000000..64cd17c
--- /dev/null
+++ b/bshell/ast/hashtable-item.c
@@ -0,0 +1,26 @@
+#include "../parse/token.h"
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct hashtable_item_ast_node *item
+		= (struct hashtable_item_ast_node *)node;
+
+	if (item->n_key) {
+		ast_iterator_enqueue(it, item->n_key);
+	}
+
+	if (item->n_value) {
+		ast_iterator_enqueue(it, item->n_value);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+struct ast_node_definition hashtable_item_ast_node = {
+	.def_id = AST_HASHTABLE_ITEM,
+	.def_node_size = sizeof(struct hashtable_item_ast_node),
+	.def_collect_children = collect_children,
+};
diff --git a/bshell/ast/hashtable.c b/bshell/ast/hashtable.c
new file mode 100644
index 0000000..ab2f612
--- /dev/null
+++ b/bshell/ast/hashtable.c
@@ -0,0 +1,24 @@
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct hashtable_ast_node *hashtable
+		= (struct hashtable_ast_node *)node;
+	fx_queue_entry *cur = fx_queue_first(&hashtable->n_items);
+	while (cur) {
+		struct ast_node *child
+			= fx_unbox(struct ast_node, cur, n_entry);
+		ast_iterator_enqueue(it, child);
+		cur = fx_queue_next(cur);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+struct ast_node_definition hashtable_ast_node = {
+	.def_id = AST_HASHTABLE,
+	.def_node_size = sizeof(struct hashtable_ast_node),
+	.def_collect_children = collect_children,
+};
diff --git a/bshell/ast/if-branch.c b/bshell/ast/if-branch.c
new file mode 100644
index 0000000..d121bb7
--- /dev/null
+++ b/bshell/ast/if-branch.c
@@ -0,0 +1,24 @@
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct if_branch_ast_node *if_branch
+		= (struct if_branch_ast_node *)node;
+	if (if_branch->n_cond) {
+		ast_iterator_enqueue(it, if_branch->n_cond);
+	}
+
+	if (if_branch->n_body) {
+		ast_iterator_enqueue(it, if_branch->n_body);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+struct ast_node_definition if_branch_ast_node = {
+	.def_id = AST_IF_BRANCH,
+	.def_node_size = sizeof(struct if_branch_ast_node),
+	.def_collect_children = collect_children,
+};
diff --git a/bshell/ast/if.c b/bshell/ast/if.c
new file mode 100644
index 0000000..db44b86
--- /dev/null
+++ b/bshell/ast/if.c
@@ -0,0 +1,23 @@
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct if_ast_node *if_group = (struct if_ast_node *)node;
+	fx_queue_entry *cur = fx_queue_first(&if_group->n_branches);
+	while (cur) {
+		struct ast_node *child
+			= fx_unbox(struct ast_node, cur, n_entry);
+		ast_iterator_enqueue(it, child);
+		cur = fx_queue_next(cur);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+struct ast_node_definition if_ast_node = {
+	.def_id = AST_IF,
+	.def_node_size = sizeof(struct if_ast_node),
+	.def_collect_children = collect_children,
+};
diff --git a/bshell/ast/null.c b/bshell/ast/null.c
new file mode 100644
index 0000000..e3f3b76
--- /dev/null
+++ b/bshell/ast/null.c
@@ -0,0 +1,7 @@
+#include "../parse/token.h"
+#include "ast.h"
+
+struct ast_node_definition null_ast_node = {
+	.def_id = AST_NULL,
+	.def_node_size = sizeof(struct null_ast_node),
+};
diff --git a/bshell/ast/op.c b/bshell/ast/op.c
new file mode 100644
index 0000000..1c3023b
--- /dev/null
+++ b/bshell/ast/op.c
@@ -0,0 +1,37 @@
+#include "../operator.h"
+#include "../parse/token.h"
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct op_ast_node *op = (struct op_ast_node *)node;
+
+	if (op->n_left) {
+		ast_iterator_enqueue(it, op->n_left);
+	}
+
+	if (op->n_right) {
+		ast_iterator_enqueue(it, op->n_right);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+static void to_string(const struct ast_node *node, fx_bstr *out)
+{
+	const struct op_ast_node *op = (const struct op_ast_node *)node;
+	fx_bstr_write_fmt(
+		out,
+		NULL,
+		"%s",
+		operator_id_to_string(op->n_op->op_id));
+}
+
+struct ast_node_definition op_ast_node = {
+	.def_id = AST_OP,
+	.def_node_size = sizeof(struct op_ast_node),
+	.def_collect_children = collect_children,
+	.def_to_string = to_string,
+};
diff --git a/bshell/ast/stmt-list.c b/bshell/ast/stmt-list.c
new file mode 100644
index 0000000..bd98255
--- /dev/null
+++ b/bshell/ast/stmt-list.c
@@ -0,0 +1,24 @@
+#include "ast.h"
+
+static enum bshell_status collect_children(
+	struct ast_node *node,
+	struct ast_iterator *it)
+{
+	struct stmt_list_ast_node *stmt_list
+		= (struct stmt_list_ast_node *)node;
+	fx_queue_entry *cur = fx_queue_first(&stmt_list->n_statements);
+	while (cur) {
+		struct ast_node *child
+			= fx_unbox(struct ast_node, cur, n_entry);
+		ast_iterator_enqueue(it, child);
+		cur = fx_queue_next(cur);
+	}
+
+	return BSHELL_SUCCESS;
+}
+
+struct ast_node_definition stmt_list_ast_node = {
+	.def_id = AST_STMT_LIST,
+	.def_node_size = sizeof(struct stmt_list_ast_node),
+	.def_collect_children = collect_children,
+};