diff --git a/CMakeLists.txt b/CMakeLists.txt
index fecc083..e388003 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,12 +22,14 @@ add_executable(fzc
 	src/compiler/checkers/fzl_loop_check.c
 	src/compiler/analyzer/utility.c
 	src/compiler/analyzer/context.c
+	src/compiler/analyzer/an_assign.c
 	src/compiler/analyzer/an_binmath.c
 	src/compiler/analyzer/an_block.c
 	src/compiler/analyzer/an_break.c
 	src/compiler/analyzer/an_call.c
 	src/compiler/analyzer/an_class.c
 	src/compiler/analyzer/an_common.c
+	src/compiler/analyzer/an_condition.c
 	src/compiler/analyzer/an_conditional.c
 	src/compiler/analyzer/an_construct.c
 	src/compiler/analyzer/an_declaration.c
@@ -36,6 +38,8 @@ add_executable(fzc
 	src/compiler/analyzer/an_identifier.c
 	src/compiler/analyzer/an_loop.c
 	src/compiler/analyzer/an_return.c
+	src/compiler/analyzer/an_unarycond.c
+	src/compiler/analyzer/an_unarymath.c
 	src/compiler/fzl_analyzer.c
 	src/compiler/fzl_debug.c
 	src/compiler/fzl_parser.c
diff --git a/include/compiler/fzl_analyzer.h b/include/compiler/fzl_analyzer.h
index 56a5794..76cced5 100644
--- a/include/compiler/fzl_analyzer.h
+++ b/include/compiler/fzl_analyzer.h
@@ -88,6 +88,10 @@ fzl_an_res_t analyze_construct(fzl_analyzer_t *analyzer, fzl_node_t *construct);
 fzl_an_res_t analyze_loop(fzl_analyzer_t *analyzer, fzl_node_t *loop_node);
 fzl_an_res_t analyze_break(fzl_analyzer_t *analyzer, fzl_node_t *break_node);
 fzl_an_res_t analyze_binmath(fzl_analyzer_t *analyzer, fzl_node_t *bin_node);
+fzl_an_res_t analyze_unarymath(fzl_analyzer_t *analyzer, fzl_node_t *unary);
+fzl_an_res_t analyze_condition(fzl_analyzer_t *analyzer, fzl_node_t *cond_node);
+fzl_an_res_t analyze_unarycond(fzl_analyzer_t *analyzer, fzl_node_t *unary);
+fzl_an_res_t analyze_assign(fzl_analyzer_t *analyzer, fzl_node_t *assign_node);
 
 fzl_an_ctx_t *an_nest_ctx(fzl_analyzer_t *analyzer, fzl_an_ctx_type_t type);
 fzl_an_ctx_t *an_fin_ctx(fzl_analyzer_t *analyzer);
diff --git a/src/compiler/analyzer/an_assign.c b/src/compiler/analyzer/an_assign.c
new file mode 100644
index 0000000..927e997
--- /dev/null
+++ b/src/compiler/analyzer/an_assign.c
@@ -0,0 +1,54 @@
+#include "common/fzl_types.h"
+#include "compiler/fzl_analyzer.h"
+#include "compiler/fzl_parser.h"
+#include <stdio.h>
+
+char asn_problem[256];
+
+// defined in `compiler/analyzer/utility.c`
+extern bool an_is_compatible(fzl_type_t a, fzl_type_t b, char *ac, char *bc);
+extern char *an_typetostr(fzl_type_t type, char *classname);
+
+// Analyze assigns
+fzl_an_res_t analyze_assign(fzl_analyzer_t *analyzer, fzl_node_t *assign_node)
+{
+  if (!analyzer)
+    return (fzl_an_res_t){.error = true};
+
+  if (!assign_node || assign_node->type != FZL_NODETYPE_ASSIGN)
+  {
+    an_push_error(analyzer, NULL, "node is not typeof ASSIGN");
+    return (fzl_an_res_t){.error = true};
+  }
+
+  fzl_node_t *left      = assign_node->binary_op.left;
+  fzl_an_res_t leftside = analyze_common(analyzer, left);
+  if (leftside.error)
+    return (fzl_an_res_t){.error = true};
+
+  fzl_an_res_t rightside =
+      analyze_common(analyzer, assign_node->binary_op.right);
+  if (rightside.error)
+    return (fzl_an_res_t){.error = true};
+
+  if (left->type != FZL_NODETYPE_DECLARATION &&
+      left->type != FZL_NODETYPE_IDENTIFIER && left->type != FZL_NODETYPE_FIELD)
+  {
+    an_push_error(analyzer, left->token,
+                  "this type of assignment left is not supported");
+    return (fzl_an_res_t){.error = true};
+  }
+
+  if (!an_is_compatible(leftside.type, rightside.type, leftside.classname,
+                        rightside.classname))
+  {
+    snprintf(asn_problem, sizeof(asn_problem), "cannot assign %s to %s",
+             an_typetostr(rightside.type, rightside.classname),
+             an_typetostr(leftside.type, leftside.classname));
+    an_push_error(analyzer, assign_node->binary_op.right->token, asn_problem);
+    return (fzl_an_res_t){.error = true};
+  }
+
+  return (fzl_an_res_t){
+      .error = false, .type = FZL_TYPE_NULL, .classname = NULL};
+}
diff --git a/src/compiler/analyzer/an_binmath.c b/src/compiler/analyzer/an_binmath.c
index 3ceb96f..2e89aac 100644
--- a/src/compiler/analyzer/an_binmath.c
+++ b/src/compiler/analyzer/an_binmath.c
@@ -11,11 +11,12 @@ fzl_an_res_t analyze_binmath(fzl_analyzer_t *analyzer, fzl_node_t *bin_node)
   if (!analyzer)
     return (fzl_an_res_t){.error = true};
 
-  if (!bin_node || bin_node->type != FZL_NODETYPE_ADD ||
-      bin_node->type != FZL_NODETYPE_SUB ||
-      bin_node->type != FZL_NODETYPE_MUL ||
-      bin_node->type != FZL_NODETYPE_DIV ||
-      bin_node->type != FZL_NODETYPE_POW || bin_node->type != FZL_NODETYPE_MOD)
+  if (!bin_node || (bin_node->type != FZL_NODETYPE_ADD &&
+                    bin_node->type != FZL_NODETYPE_SUB &&
+                    bin_node->type != FZL_NODETYPE_MUL &&
+                    bin_node->type != FZL_NODETYPE_DIV &&
+                    bin_node->type != FZL_NODETYPE_POW &&
+                    bin_node->type != FZL_NODETYPE_MOD))
   {
     an_push_error(analyzer, NULL, "node is not typeof binary math");
     return (fzl_an_res_t){.error = true};
diff --git a/src/compiler/analyzer/an_common.c b/src/compiler/analyzer/an_common.c
index c893867..a8f43fb 100644
--- a/src/compiler/analyzer/an_common.c
+++ b/src/compiler/analyzer/an_common.c
@@ -11,6 +11,30 @@ fzl_an_res_t analyze_common(fzl_analyzer_t *analyzer, fzl_node_t *node)
   fzl_an_res_t res = {.error = false, .type = FZL_TYPE_NULL, .classname = NULL};
   switch (node->type)
   {
+    case FZL_NODETYPE_ASSIGN:
+      res = analyze_assign(analyzer, node);
+      break;
+
+    case FZL_NODETYPE_NOT:
+      res = analyze_unarycond(analyzer, node);
+      break;
+
+    case FZL_NODETYPE_OR:
+    case FZL_NODETYPE_AND:
+    case FZL_NODETYPE_LESS:
+    case FZL_NODETYPE_LESS_EQUAL:
+    case FZL_NODETYPE_GREATER:
+    case FZL_NODETYPE_GREATER_EQUAL:
+    case FZL_NODETYPE_EQUAL:
+    case FZL_NODETYPE_NEQUAL:
+      res = analyze_condition(analyzer, node);
+      break;
+
+    case FZL_NODETYPE_UNARY_MINUS:
+    case FZL_NODETYPE_UNARY_PLUS:
+      res = analyze_unarymath(analyzer, node);
+      break;
+
     case FZL_NODETYPE_ADD:
     case FZL_NODETYPE_SUB:
     case FZL_NODETYPE_MUL:
diff --git a/src/compiler/analyzer/an_condition.c b/src/compiler/analyzer/an_condition.c
new file mode 100644
index 0000000..0a0505b
--- /dev/null
+++ b/src/compiler/analyzer/an_condition.c
@@ -0,0 +1,122 @@
+#include <common/fzl_types.h>
+#include <compiler/fzl_analyzer.h>
+#include <compiler/fzl_parser.h>
+#include <stdio.h>
+
+char bincond_problem[256];
+
+// defined in `compiler/analyzer/utility.c`
+extern bool an_is_compatible(fzl_type_t a, fzl_type_t b, char *ac, char *bc);
+extern char *an_typetostr(fzl_type_t type, char *classname);
+
+// Analyze binary conditional nodes
+fzl_an_res_t analyze_condition(fzl_analyzer_t *analyzer, fzl_node_t *cond_node)
+{
+  if (!analyzer)
+    return (fzl_an_res_t){.error = true};
+
+  if (!cond_node || (cond_node->type != FZL_NODETYPE_OR &&
+                     cond_node->type != FZL_NODETYPE_AND &&
+                     cond_node->type != FZL_NODETYPE_LESS &&
+                     cond_node->type != FZL_NODETYPE_LESS_EQUAL &&
+                     cond_node->type != FZL_NODETYPE_GREATER &&
+                     cond_node->type != FZL_NODETYPE_GREATER_EQUAL &&
+                     cond_node->type != FZL_NODETYPE_EQUAL &&
+                     cond_node->type != FZL_NODETYPE_NEQUAL))
+  {
+    an_push_error(analyzer, NULL, "node is not typeof binary condition");
+    return (fzl_an_res_t){.error = true};
+  }
+
+  fzl_an_res_t left = analyze_common(analyzer, cond_node->binary_op.left);
+  if (left.error)
+    return (fzl_an_res_t){.error = true};
+
+  fzl_an_res_t right = analyze_common(analyzer, cond_node->binary_op.right);
+  if (right.error)
+    return (fzl_an_res_t){.error = true};
+
+  if (cond_node->type == FZL_NODETYPE_OR || cond_node->type == FZL_NODETYPE_AND)
+  {
+    if (left.type != FZL_TYPE_BOOL)
+      an_push_warning(analyzer, cond_node->binary_op.left->token,
+                      "left operand is not resulting with boolean type");
+
+    if (right.type != FZL_TYPE_BOOL)
+      an_push_warning(analyzer, cond_node->binary_op.right->token,
+                      "right operand is not resulting with boolean type");
+  }
+  else if (cond_node->type == FZL_NODETYPE_LESS ||
+           cond_node->type == FZL_NODETYPE_LESS_EQUAL ||
+           cond_node->type == FZL_NODETYPE_GREATER ||
+           cond_node->type == FZL_NODETYPE_GREATER_EQUAL)
+  {
+    if (left.type < FZL_TYPE_INT8)
+    {
+      an_push_error(analyzer, cond_node->binary_op.left->token,
+                    "left operand must be number");
+      return (fzl_an_res_t){.error = true};
+    }
+
+    if (left.type < FZL_TYPE_INT8)
+    {
+      an_push_error(analyzer, cond_node->binary_op.left->token,
+                    "right operand must be number");
+      return (fzl_an_res_t){.error = true};
+    }
+  }
+  else if (left.type >= FZL_TYPE_INT8)
+  {
+    if (right.type < FZL_TYPE_INT8)
+    {
+      an_push_error(analyzer, cond_node->binary_op.right->token,
+                    "right operand must be an integer");
+      return (fzl_an_res_t){.error = true};
+    }
+
+    return (fzl_an_res_t){
+        .error = false, .type = FZL_TYPE_BOOL, .classname = NULL};
+  }
+  else if (left.type == FZL_TYPE_OBJECT)
+  {
+    if (!left.classname || !right.classname)
+    {
+      an_push_error(analyzer, cond_node->binary_op.left->token,
+                    "unhandled error :(");
+      return (fzl_an_res_t){.error = true};
+    }
+
+    if (!an_is_compatible(left.type, right.type, left.classname,
+                          right.classname))
+    {
+      snprintf(bincond_problem, sizeof(bincond_problem),
+               "'%s' and '%s' are incompatible",
+               an_typetostr(left.type, left.classname),
+               an_typetostr(right.type, right.classname));
+      an_push_error(analyzer, cond_node->binary_op.right->token,
+                    bincond_problem);
+      return (fzl_an_res_t){.error = true};
+    }
+  }
+  else if (left.type == FZL_TYPE_STRING)
+  {
+    if (right.type != FZL_TYPE_STRING)
+    {
+      an_push_error(analyzer, cond_node->binary_op.right->token,
+                    "right operand must be a string");
+      return (fzl_an_res_t){.error = true};
+    }
+  }
+  else if (!an_is_compatible(left.type, right.type, left.classname,
+                             right.classname))
+  {
+    snprintf(bincond_problem, sizeof(bincond_problem),
+             "equality not supported between %s and %s",
+             an_typetostr(left.type, left.classname),
+             an_typetostr(right.type, right.classname));
+    return (fzl_an_res_t){.error = true};
+  }
+
+  return (fzl_an_res_t){
+      .error = false, .type = FZL_TYPE_BOOL, .classname = NULL};
+}
diff --git a/src/compiler/analyzer/an_declaration.c b/src/compiler/analyzer/an_declaration.c
index a6bc786..efc0300 100644
--- a/src/compiler/analyzer/an_declaration.c
+++ b/src/compiler/analyzer/an_declaration.c
@@ -67,5 +67,5 @@ fzl_an_res_t analyze_declaration(fzl_analyzer_t *analyzer, fzl_node_t *decl)
                          classname);
   }
 
-  return (fzl_an_res_t){.error = false, .type = FZL_TYPE_NULL};
+  return (fzl_an_res_t){.error = false, .type = type, .classname = classname};
 }
diff --git a/src/compiler/analyzer/an_unarycond.c b/src/compiler/analyzer/an_unarycond.c
new file mode 100644
index 0000000..29123dc
--- /dev/null
+++ b/src/compiler/analyzer/an_unarycond.c
@@ -0,0 +1,30 @@
+#include <common/fzl_types.h>
+#include <compiler/fzl_analyzer.h>
+#include <compiler/fzl_parser.h>
+
+// Analyze unary condition
+fzl_an_res_t analyze_unarycond(fzl_analyzer_t *analyzer, fzl_node_t *unary)
+{
+  if (!analyzer)
+    return (fzl_an_res_t){.error = true};
+
+  if (!unary || unary->type != FZL_NODETYPE_NOT)
+  {
+    an_push_error(analyzer, NULL, "node is not typeof unary condition");
+    return (fzl_an_res_t){.error = true};
+  }
+
+  fzl_an_res_t operand_res = analyze_common(analyzer, unary->unary_op.operand);
+  if (operand_res.error)
+    return (fzl_an_res_t){.error = true};
+
+  if (operand_res.type != FZL_TYPE_BOOL && operand_res.type < FZL_TYPE_INT8)
+  {
+    an_push_error(analyzer, unary->unary_op.operand->token,
+                  "unary condition only support bool and integer types");
+    return (fzl_an_res_t){.error = true};
+  }
+
+  return (fzl_an_res_t){
+      .error = false, .type = FZL_TYPE_BOOL, .classname = NULL};
+}
diff --git a/src/compiler/analyzer/an_unarymath.c b/src/compiler/analyzer/an_unarymath.c
new file mode 100644
index 0000000..6df52a5
--- /dev/null
+++ b/src/compiler/analyzer/an_unarymath.c
@@ -0,0 +1,32 @@
+#include <common/fzl_types.h>
+#include <compiler/fzl_analyzer.h>
+#include <compiler/fzl_parser.h>
+#include <stdbool.h>
+
+// Analyze unary arithmetic
+fzl_an_res_t analyze_unarymath(fzl_analyzer_t *analyzer, fzl_node_t *unary)
+{
+  if (!analyzer)
+    return (fzl_an_res_t){.error = true};
+
+  if (!unary || (unary->type != FZL_NODETYPE_UNARY_MINUS &&
+                 unary->type != FZL_NODETYPE_UNARY_PLUS))
+  {
+    an_push_error(analyzer, NULL, "node is not typeof unary math");
+    return (fzl_an_res_t){.error = true};
+  }
+
+  fzl_an_res_t operand_res = analyze_common(analyzer, unary->unary_op.operand);
+  if (operand_res.error)
+    return (fzl_an_res_t){.error = true};
+
+  if (operand_res.type < FZL_TYPE_INT8)
+  {
+    an_push_error(analyzer, unary->unary_op.operand->token,
+                  "unary operator only support integer types");
+    return (fzl_an_res_t){.error = true};
+  }
+
+  return (fzl_an_res_t){
+      .error = false, .type = operand_res.type, .classname = NULL};
+}