diff --git a/.github/workflows/build-check-sdk.yaml b/.github/workflows/build-check-sdk.yaml
index 10a4811..b17b734 100644
--- a/.github/workflows/build-check-sdk.yaml
+++ b/.github/workflows/build-check-sdk.yaml
@@ -2,7 +2,7 @@ name: "Build check gemstone in SDK"
 run-name: SDK build check to ${{ inputs.deploy_target }} by @${{ github.actor }}
 on: [push, pull_request]
 env:
-  SDK: 0.2.2-alpine-3.19.1
+  SDK: 0.2.3-alpine-3.19.1
 jobs:
   build-check-sdk:
     runs-on: ubuntu-latest
diff --git a/Dockerfile b/Dockerfile
index 09e34b6..a8c2f7f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,6 @@
-FROM servostar/gemstone:sdk-0.2.2-alpine-3.19.1
+FROM servostar/gemstone:sdk-0.2.3-alpine-3.19.1
 LABEL authors="servostar"
-LABEL version="0.2.2"
+LABEL version="0.2.3"
 LABEL description="docker image for setting up the build pipeline on SDK"
 LABEL website="https://github.com/Servostar/gemstone"
 
diff --git a/sdk/Dockerfile b/sdk/Dockerfile
index 1a6a677..aae7438 100644
--- a/sdk/Dockerfile
+++ b/sdk/Dockerfile
@@ -1,11 +1,11 @@
 FROM alpine:3.19.1
 LABEL authors="servostar"
-LABEL version="0.2.2"
+LABEL version="0.2.3"
 LABEL description="base image for building the gemstone programming language compiler"
 LABEL website="https://github.com/Servostar/gemstone"
 
 # install dependencies
-RUN apk add build-base gcc make cmake bison flex git python3
+RUN apk add build-base gcc make cmake bison flex git python3 graphviz
 
 # create user for build
 RUN adduser --disabled-password lorang
diff --git a/src/ast/ast.c b/src/ast/ast.c
index a9c820b..efd737b 100644
--- a/src/ast/ast.c
+++ b/src/ast/ast.c
@@ -3,12 +3,13 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/log.h>
+#include <assert.h>
 #include <gc/gc.h>
 
-struct AST_Node_t *AST_new_node(enum AST_SyntaxElement_t kind, const char* value) {
+AST_NODE_PTR AST_new_node(enum AST_SyntaxElement_t kind, const char* value) {
   DEBUG("creating new AST node: %d \"%s\"", kind, value);
 
-  struct AST_Node_t *node = malloc(sizeof(struct AST_Node_t));
+  AST_NODE_PTR node = malloc(sizeof(struct AST_Node_t));
 
   if (node == NULL) {
     PANIC("failed to allocate AST node");
@@ -18,6 +19,7 @@ struct AST_Node_t *AST_new_node(enum AST_SyntaxElement_t kind, const char* value
   node->parent = NULL;
   node->children = NULL;
   node->child_count = 0;
+  node->child_cap = 0;
   node->kind = kind;
   node->value = value;
 
@@ -26,11 +28,12 @@ struct AST_Node_t *AST_new_node(enum AST_SyntaxElement_t kind, const char* value
 
 static const char* lookup_table[AST_ELEMENT_COUNT] = { "__UNINIT__" };
 
-void AST_init() {
+void AST_init(void) {
   DEBUG("initializing global syntax tree...");
 
   INFO("filling lookup table...");
 
+  lookup_table[AST_Stmt] = "stmt";
   lookup_table[AST_Expr] = "expr";
 
   lookup_table[AST_Add] = "+";
@@ -64,6 +67,10 @@ void AST_init() {
   lookup_table[AST_Typedef] = "typedef";
   lookup_table[AST_Box] = "box";
   lookup_table[AST_Fun] = "fun";
+
+  lookup_table[AST_Typecast] = "cast";
+  lookup_table[AST_Transmute] = "as";
+  lookup_table[AST_Condition] = "condition";
 }
 
 const char* AST_node_to_string(struct AST_Node_t* node) {
@@ -78,6 +85,7 @@ const char* AST_node_to_string(struct AST_Node_t* node) {
     case AST_Ident:
     case AST_Macro:
     case AST_Import:
+    case AST_Call:
       string = node->value;
       break;
     default:
@@ -87,17 +95,24 @@ const char* AST_node_to_string(struct AST_Node_t* node) {
   return string;
 }
 
-void AST_push_node(struct AST_Node_t *owner, struct AST_Node_t *child) {
+#define PRE_ALLOCATION_CNT 10
+
+void AST_push_node(AST_NODE_PTR owner, AST_NODE_PTR child) {
   DEBUG("Adding new node %p to %p", child, owner);
 
+  assert(PRE_ALLOCATION_CNT >= 1);
+
   // if there are no children for now
-  if (owner->child_count == 0) {
+  if (owner->children == NULL) {
+    assert(owner->child_count == 0);
     DEBUG("Allocating new children array");
     owner->children = malloc(sizeof(struct AST_Node_t *));
+    owner->child_cap = 1;
 
-  } else {
-    DEBUG("Rellocating old children array");
-    const size_t size = sizeof(struct AST_Node_t *) * (owner->child_count + 1);
+  } else if (owner->child_count >= owner->child_cap) {
+    DEBUG("Reallocating old children array");
+    owner->child_cap += PRE_ALLOCATION_CNT;
+    const size_t size = sizeof(struct AST_Node_t *) * owner->child_cap;
     owner->children = realloc(owner->children, size);
   }
 
@@ -108,8 +123,8 @@ void AST_push_node(struct AST_Node_t *owner, struct AST_Node_t *child) {
   owner->children[owner->child_count++] = child;
 }
 
-struct AST_Node_t *AST_get_node(struct AST_Node_t *owner, size_t idx) {
-  DEBUG("retrvieng node %d from %p", idx, owner);
+AST_NODE_PTR AST_get_node(AST_NODE_PTR owner, size_t idx) {
+  DEBUG("retrieving node %d from %p", idx, owner);
 
   if (owner == NULL) {
     PANIC("AST owner node is NULL");
@@ -119,7 +134,7 @@ struct AST_Node_t *AST_get_node(struct AST_Node_t *owner, size_t idx) {
     PANIC("AST owner node has no children");
   }
 
-  struct AST_Node_t *child = owner->children[idx];
+  AST_NODE_PTR child = owner->children[idx];
 
   if (child == NULL) {
     PANIC("child node is NULL");
@@ -128,20 +143,48 @@ struct AST_Node_t *AST_get_node(struct AST_Node_t *owner, size_t idx) {
   return child;
 }
 
-void AST_delete_node(struct AST_Node_t *node) {
-  DEBUG("Deleting AST node: %p", node);
+void AST_delete_node(AST_NODE_PTR node) {
+    DEBUG("Deleting AST node: %p", node);
 
-  if (node == NULL) {
-    PANIC("Node to free is NULL");
-  }
+    if (node == NULL) {
+        PANIC("Node to free is NULL");
+    }
 
-  if (node->children == NULL) {
-    return;
-  }
+    if (node->parent != NULL) {
+        AST_detach_node(node->parent, node);
+    }
 
-  for (size_t i = 0; i < node->child_count; i++) {
-    AST_delete_node(node->children[i]);
-  }
+    if (node->children == NULL) {
+        return;
+    }
+
+    for (size_t i = 0; i < node->child_count; i++) {
+        if (node->children[i] != node) {
+            AST_delete_node(node->children[i]);
+        } else {
+            WARN("Circular dependency in AST: parent -> child -> parent -> child -> ...");
+        }
+    }
+
+    free(node->children);
+    free(node);
+}
+
+AST_NODE_PTR AST_detach_node(AST_NODE_PTR parent, AST_NODE_PTR child) {
+    assert(parent != NULL);
+    assert(child != NULL);
+
+    for (size_t i = 0; i < parent->child_count; i++) {
+        if (child == parent->children[i]) {
+            memcpy(&parent->children[i], &parent->children[i + 1], parent->child_count - i - 1);
+            parent->child_count--;
+            return child;
+        }
+    }
+
+    WARN("Node not a child of parent");
+
+    return child;
 }
 
 static void __AST_visit_nodes_recurse2(struct AST_Node_t *root,
diff --git a/src/ast/ast.h b/src/ast/ast.h
index 486a520..13437ea 100644
--- a/src/ast/ast.h
+++ b/src/ast/ast.h
@@ -17,6 +17,7 @@ enum AST_SyntaxElement_t {
   AST_If,
   AST_IfElse,
   AST_Else,
+  AST_Condition,
   // Variable management
   AST_Decl,
   AST_Assign,
@@ -68,6 +69,7 @@ struct AST_Node_t {
   // number of child nodes ownd by this node
   // length of children array
   size_t child_count;
+  size_t child_cap;
   // variable amount of child nodes
   struct AST_Node_t **children;
 };
@@ -89,6 +91,8 @@ void AST_delete_node(struct AST_Node_t *);
 // add a new child node
 void AST_push_node(struct AST_Node_t *owner, struct AST_Node_t *child);
 
+AST_NODE_PTR AST_detach_node(AST_NODE_PTR parent, AST_NODE_PTR child);
+
 // get a specific child node
 struct AST_Node_t *AST_get_node(struct AST_Node_t *owner, size_t idx);
 
diff --git a/tests/ast/CMakeLists.txt b/tests/ast/CMakeLists.txt
index 81e7b96..455130b 100644
--- a/tests/ast/CMakeLists.txt
+++ b/tests/ast/CMakeLists.txt
@@ -24,12 +24,28 @@ add_test(NAME ast_build_tree
 
 add_executable(ast_print_node
         ${PROJECT_SOURCE_DIR}/src/ast/ast.c
+        ${PROJECT_SOURCE_DIR}/src/sys/log.c
         print_node.c)
-set_target_properties(ast_build_tree
+set_target_properties(ast_print_node
         PROPERTIES
-        OUTPUT_NAME "build_tree"
+        OUTPUT_NAME "print_node"
         RUNTIME_OUTPUT_DIRECTORY ${GEMSTONE_BINARY_DIR}/tests/ast)
 add_test(NAME ast_print_node
         WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
         COMMAND python ${GEMSTONE_TEST_DIR}/ast/test_ast.py check_print_node)
 
+# ------------------------------------------------------- #
+# CTEST 3
+# test graphviz output
+
+add_executable(ast_graphviz
+        ${PROJECT_SOURCE_DIR}/src/ast/ast.c
+        ${PROJECT_SOURCE_DIR}/src/sys/log.c
+        print_graphviz.c)
+set_target_properties(ast_graphviz
+        PROPERTIES
+        OUTPUT_NAME "print_graphviz"
+        RUNTIME_OUTPUT_DIRECTORY ${GEMSTONE_BINARY_DIR}/tests/ast)
+add_test(NAME ast_graphviz
+        WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+        COMMAND python ${GEMSTONE_TEST_DIR}/ast/test_ast.py check_print_graphviz)
diff --git a/tests/ast/print_graphviz.c b/tests/ast/print_graphviz.c
new file mode 100644
index 0000000..6df64b4
--- /dev/null
+++ b/tests/ast/print_graphviz.c
@@ -0,0 +1,54 @@
+//
+// Created by servostar on 5/8/24.
+//
+
+#include <ast/ast.h>
+#include <sys/log.h>
+
+void generate_statement(const AST_NODE_PTR stmt) {
+    const AST_NODE_PTR add = AST_new_node(AST_Add, NULL);
+
+    AST_push_node(add, AST_new_node(AST_Int, "3"));
+    AST_push_node(add, AST_new_node(AST_Int, "6"));
+
+    AST_push_node(stmt, add);
+}
+
+void generate_branch(const AST_NODE_PTR stmt) {
+    const AST_NODE_PTR branch = AST_new_node(AST_If, NULL);
+    const AST_NODE_PTR gt = AST_new_node(AST_Greater, NULL);
+
+    AST_push_node(branch, gt);
+
+    AST_push_node(gt, AST_new_node(AST_Float, "2.3"));
+    AST_push_node(gt, AST_new_node(AST_Float, "0.79"));
+
+    AST_push_node(stmt, branch);
+
+    generate_statement(branch);
+}
+
+int main(void) {
+
+    AST_init();
+
+    const AST_NODE_PTR root = AST_new_node(AST_Stmt, NULL);
+
+    generate_branch(root);
+
+    FILE* output = fopen("tmp/graph.gv", "w");
+
+    if (output == NULL) {
+        PANIC("unable to open file");
+    }
+
+    AST_fprint_graphviz(output, root);
+
+    fflush(output);
+
+    fclose(output);
+
+    AST_delete_node(root);
+
+    return 0;
+}
diff --git a/tests/ast/print_node.c b/tests/ast/print_node.c
index 83d3d43..38e8a41 100644
--- a/tests/ast/print_node.c
+++ b/tests/ast/print_node.c
@@ -6,6 +6,8 @@
 
 int main(void) {
 
+    AST_init();
+
     const AST_NODE_PTR node = AST_new_node(0, "value");
 
     for (size_t i = 0; i < AST_ELEMENT_COUNT; i++) {
@@ -16,4 +18,6 @@ int main(void) {
     }
 
     AST_delete_node(node);
+
+    return 0;
 }
diff --git a/tests/ast/test_ast.py b/tests/ast/test_ast.py
index 111e9c3..0f9b757 100644
--- a/tests/ast/test_ast.py
+++ b/tests/ast/test_ast.py
@@ -28,6 +28,84 @@ def run_check_print_node():
     # check exit code
     assert p.returncode == 0
 
+    assert """0 stmt
+1 expr
+2 value
+3 value
+4 value
+5 while
+6 if
+7 else if
+8 else
+9 condition
+10 decl
+11 assign
+12 def
+13 value
+14 +
+15 -
+16 *
+17 /
+18 &
+19 |
+20 ^
+21 !
+22 &&
+23 ||
+24 ^^
+25 !!
+26 ==
+27 >
+28 <
+29 cast
+30 as
+31 value
+32 value
+33 typedef
+34 box
+35 fun
+36 value
+""" == p.stdout
+
+
+def run_check_print_graphviz():
+    info("started check print graphviz...")
+
+    info("creating temporary folder...")
+
+    if not os.path.exists("tmp"):
+        os.mkdir("tmp")
+
+    info("cleaning temporary folder...")
+
+    if os.path.exists("tmp/graph.gv"):
+        os.remove("tmp/graph.gv")
+
+    if os.path.exists("tmp/graph.svg"):
+        os.remove("tmp/graph.svg")
+
+    p = subprocess.run(BIN_DIR + "print_graphviz", capture_output=True, text=True)
+
+    info("checking exit code...")
+
+    # check exit code
+    assert p.returncode == 0
+
+    info("converting gv to svg...")
+
+    p = subprocess.run(["dot", "-Tsvg", "tmp/graph.gv", "-otmp/graph.svg"])
+
+    info("checking exit code...")
+    assert p.returncode == 0
+
+    info("checking svg output...")
+    with open("tmp/graph.svg", "r") as file:
+        string = "".join(file.readlines())
+        assert "2.3" in string
+        assert "0.79" in string
+        assert "stmt" in string
+        assert "if" in string
+
 
 if __name__ == "__main__":
     logging.basicConfig(level=logging.INFO)
@@ -41,6 +119,8 @@ if __name__ == "__main__":
             run_check_build_tree()
         case "check_print_node":
             run_check_print_node()
+        case "check_print_graphviz":
+            run_check_print_graphviz()
         case _:
             error(f"unknown target: {target}")
             exit(1)