diff --git a/Aegis/Parser.lean b/Aegis/Parser.lean
index b28442e..3d69405 100644
--- a/Aegis/Parser.lean
+++ b/Aegis/Parser.lean
@@ -223,3 +223,44 @@ def parseIdentifier (input : String) : CoreM (Except String Identifier) := do
   let env ← getEnv
   let input := replaceNaughtyBrackets input
   pure do elabIdentifier (← runParserCategory env `identifier input)
+
+def parseJsonTypedef (j : Lean.Json) : CoreM (Identifier × Identifier) := do
+  let .ok lhs := j.getObjVal? "id"
+    | throwError "typedef must include id"
+  let .ok (.str lhs) := lhs.getObjVal? "debug_name"
+    | throwError "dbug_name must be a string!"
+  let .ok lhs ← parseIdentifier lhs
+    | throwError "cannot parse lhs identifier of type def"
+  pure (lhs, lhs)  -- TODO
+
+def parseJsonDeclaration (j : Lean.Json) :
+    CoreM (Identifier × Nat × List (Nat × Identifier) × List Identifier) := do
+  let .ok id := j.getObjVal? "id"
+    | throwError "declaration must include id"
+  let .ok (.str id) := id.getObjVal? "debug_name"
+    | throwError "dbug_name must be a string!"
+  let .ok id ← parseIdentifier id
+    | throwError "cannot parse lhs identifier of type def"
+  let .ok (.num ⟨.ofNat n, 0⟩) := j.getObjVal? "entry_point"
+    | throwError "declaration must include entry_point"
+  pure (id, n, [], [])  -- TODO
+
+def parseJson (j : Lean.Json) : CoreM SierraFile := do
+  -- Descend into "sierra_program" if we are in the output of snforge
+  let j := match j.getObjVal? "sierra_program" with
+    | .ok j' => j'
+    | .error _ => j
+  let .ok (.arr typedefs) := j.getObjVal? "type_declarations"
+    | throwError "Typedefs must be an array!"
+  let typedefs ← typedefs.mapM parseJsonTypedef
+  let .ok (.arr libfuncs) := j.getObjVal? "libfunc_declarations"
+    | throwError "Libfuncs must be an array!"
+  let .ok (.arr statements) := j.getObjVal? "statements"
+    | throwError "Statements must be an array!"
+  let .ok (.arr declarations) := j.getObjVal? "funcs"
+    | throwError "Declaractions must be an array!"
+  let declarations ← declarations.mapM parseJsonDeclaration
+  pure { typedefs := typedefs.toList
+         libfuncs := []
+         statements := []
+         declarations := declarations.toList }
diff --git a/Aegis/Tests/Json.lean b/Aegis/Tests/Json.lean
new file mode 100644
index 0000000..920138d
--- /dev/null
+++ b/Aegis/Tests/Json.lean
@@ -0,0 +1,1551 @@
+import Aegis.Commands
+
+def fib_jumps_input : String := "{
+  \"version\": 1,
+  \"type_declarations\": [
+    {
+      \"id\": {
+        \"id\": 18197987107266074389,
+        \"debug_name\": \"felt252\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"felt252\",
+        \"generic_args\": []
+      },
+      \"declared_type_info\": null
+    },
+    {
+      \"id\": {
+        \"id\": 8338741463261264245,
+        \"debug_name\": \"GasBuiltin\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"GasBuiltin\",
+        \"generic_args\": []
+      },
+      \"declared_type_info\": null
+    },
+    {
+      \"id\": {
+        \"id\": 5158587525321846130,
+        \"debug_name\": \"RangeCheck\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"RangeCheck\",
+        \"generic_args\": []
+      },
+      \"declared_type_info\": null
+    },
+    {
+      \"id\": {
+        \"id\": 12132746703728246991,
+        \"debug_name\": \"NonZeroInt\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"NonZero\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 18197987107266074389,
+              \"debug_name\": \"felt252\"
+            }
+          }
+        ]
+      },
+      \"declared_type_info\": null
+    }
+  ],
+  \"libfunc_declarations\": [
+    {
+      \"id\": {
+        \"id\": 3328301606880823183,
+        \"debug_name\": \"branch_align\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"branch_align\",
+        \"generic_args\": []
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 5573091817713561949,
+        \"debug_name\": \"felt252_add\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"felt252_add\",
+        \"generic_args\": []
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 5747884298157259530,
+        \"debug_name\": \"felt252_const_0\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"felt252_const\",
+        \"generic_args\": [
+          {
+            \"Value\": [
+              0,
+              []
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 5747885397668887741,
+        \"debug_name\": \"felt252_const_1\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"felt252_const\",
+        \"generic_args\": [
+          {
+            \"Value\": [
+              1,
+              [
+                1
+              ]
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 3075775707538119114,
+        \"debug_name\": \"felt252_const_minus_1\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"felt252_const\",
+        \"generic_args\": [
+          {
+            \"Value\": [
+              -1,
+              [
+                1
+              ]
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 6741348721511978627,
+        \"debug_name\": \"felt252_drop\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"drop\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 18197987107266074389,
+              \"debug_name\": \"felt252\"
+            }
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 2468470103186650467,
+        \"debug_name\": \"felt252_dup\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"dup\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 18197987107266074389,
+              \"debug_name\": \"felt252\"
+            }
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 4730041110748051225,
+        \"debug_name\": \"felt252_is_zero\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"felt252_is_zero\",
+        \"generic_args\": []
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 10451117352454336008,
+        \"debug_name\": \"felt252_sub_1\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"felt252_sub_const\",
+        \"generic_args\": [
+          {
+            \"Value\": [
+              1,
+              [
+                1
+              ]
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 9547199891349871288,
+        \"debug_name\": \"felt252_unwrap_non_zero\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"unwrap_non_zero\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 18197987107266074389,
+              \"debug_name\": \"felt252\"
+            }
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 566598754701111445,
+        \"debug_name\": \"withdraw_gas\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"withdraw_gas\",
+        \"generic_args\": []
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 16940139219101328589,
+        \"debug_name\": \"jump\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"jump\",
+        \"generic_args\": []
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 17829783910969655620,
+        \"debug_name\": \"redeposit_gas\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"redeposit_gas\",
+        \"generic_args\": []
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 940060015955306962,
+        \"debug_name\": \"rename_felt252\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"rename\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 18197987107266074389,
+              \"debug_name\": \"felt252\"
+            }
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 16869075576697926123,
+        \"debug_name\": \"revoke_ap_tracking\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"revoke_ap_tracking\",
+        \"generic_args\": []
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 14115798396771957644,
+        \"debug_name\": \"store_temp_felt252\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"store_temp\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 18197987107266074389,
+              \"debug_name\": \"felt252\"
+            }
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 7943736942875005115,
+        \"debug_name\": \"store_temp_gb\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"store_temp\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 8338741463261264245,
+              \"debug_name\": \"GasBuiltin\"
+            }
+          }
+        ]
+      }
+    },
+    {
+      \"id\": {
+        \"id\": 7931306963920539685,
+        \"debug_name\": \"store_temp_rc\"
+      },
+      \"long_id\": {
+        \"generic_id\": \"store_temp\",
+        \"generic_args\": [
+          {
+            \"Type\": {
+              \"id\": 5158587525321846130,
+              \"debug_name\": \"RangeCheck\"
+            }
+          }
+        ]
+      }
+    }
+  ],
+  \"statements\": [
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 16869075576697926123,
+          \"debug_name\": \"revoke_ap_tracking\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 4730041110748051225,
+          \"debug_name\": \"felt252_is_zero\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          },
+          {
+            \"target\": {
+              \"Statement\": 9
+            },
+            \"results\": [
+              {
+                \"id\": 12638194897137039473,
+                \"debug_name\": \"n\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 3328301606880823183,
+          \"debug_name\": \"branch_align\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7931306963920539685,
+          \"debug_name\": \"store_temp_rc\"
+        },
+        \"args\": [
+          {
+            \"id\": 638478738777676098,
+            \"debug_name\": \"rc\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 638478738777676098,
+                \"debug_name\": \"rc\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 17829783910969655620,
+          \"debug_name\": \"redeposit_gas\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7943736942875005115,
+          \"debug_name\": \"store_temp_gb\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 5747885397668887741,
+          \"debug_name\": \"felt252_const_1\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 1875936269717626031,
+                \"debug_name\": \"one\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 1875936269717626031,
+            \"debug_name\": \"one\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 1875936269717626031,
+                \"debug_name\": \"one\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Return\": [
+        {
+          \"id\": 638478738777676098,
+          \"debug_name\": \"rc\"
+        },
+        {
+          \"id\": 618457731543555724,
+          \"debug_name\": \"gb\"
+        },
+        {
+          \"id\": 1875936269717626031,
+          \"debug_name\": \"one\"
+        }
+      ]
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 3328301606880823183,
+          \"debug_name\": \"branch_align\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 9547199891349871288,
+          \"debug_name\": \"felt252_unwrap_non_zero\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638194897137039473,
+                \"debug_name\": \"n\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638194897137039473,
+                \"debug_name\": \"n\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7931306963920539685,
+          \"debug_name\": \"store_temp_rc\"
+        },
+        \"args\": [
+          {
+            \"id\": 638478738777676098,
+            \"debug_name\": \"rc\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 638478738777676098,
+                \"debug_name\": \"rc\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7943736942875005115,
+          \"debug_name\": \"store_temp_gb\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 5747885397668887741,
+          \"debug_name\": \"felt252_const_1\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638187200555641996,
+                \"debug_name\": \"a\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638187200555641996,
+            \"debug_name\": \"a\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638187200555641996,
+                \"debug_name\": \"a\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 5747884298157259530,
+          \"debug_name\": \"felt252_const_0\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638190499090526629,
+                \"debug_name\": \"b\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638190499090526629,
+            \"debug_name\": \"b\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638190499090526629,
+                \"debug_name\": \"b\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 4730041110748051225,
+          \"debug_name\": \"felt252_is_zero\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          },
+          {
+            \"target\": {
+              \"Statement\": 26
+            },
+            \"results\": [
+              {
+                \"id\": 12638194897137039473,
+                \"debug_name\": \"n\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 3328301606880823183,
+          \"debug_name\": \"branch_align\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 6741348721511978627,
+          \"debug_name\": \"felt252_drop\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638190499090526629,
+            \"debug_name\": \"b\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7931306963920539685,
+          \"debug_name\": \"store_temp_rc\"
+        },
+        \"args\": [
+          {
+            \"id\": 638478738777676098,
+            \"debug_name\": \"rc\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 638478738777676098,
+                \"debug_name\": \"rc\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 17829783910969655620,
+          \"debug_name\": \"redeposit_gas\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7943736942875005115,
+          \"debug_name\": \"store_temp_gb\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638187200555641996,
+            \"debug_name\": \"a\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638187200555641996,
+                \"debug_name\": \"a\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Return\": [
+        {
+          \"id\": 638478738777676098,
+          \"debug_name\": \"rc\"
+        },
+        {
+          \"id\": 618457731543555724,
+          \"debug_name\": \"gb\"
+        },
+        {
+          \"id\": 12638187200555641996,
+          \"debug_name\": \"a\"
+        }
+      ]
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 3328301606880823183,
+          \"debug_name\": \"branch_align\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 9547199891349871288,
+          \"debug_name\": \"felt252_unwrap_non_zero\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638194897137039473,
+                \"debug_name\": \"n\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 566598754701111445,
+          \"debug_name\": \"withdraw_gas\"
+        },
+        \"args\": [
+          {
+            \"id\": 638478738777676098,
+            \"debug_name\": \"rc\"
+          },
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 638478738777676098,
+                \"debug_name\": \"rc\"
+              },
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          },
+          {
+            \"target\": {
+              \"Statement\": 40
+            },
+            \"results\": [
+              {
+                \"id\": 638478738777676098,
+                \"debug_name\": \"rc\"
+              },
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 3328301606880823183,
+          \"debug_name\": \"branch_align\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 2468470103186650467,
+          \"debug_name\": \"felt252_dup\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638187200555641996,
+            \"debug_name\": \"a\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638187200555641996,
+                \"debug_name\": \"a\"
+              },
+              {
+                \"id\": 5124477032042102868,
+                \"debug_name\": \"prev_a\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 5573091817713561949,
+          \"debug_name\": \"felt252_add\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638187200555641996,
+            \"debug_name\": \"a\"
+          },
+          {
+            \"id\": 12638190499090526629,
+            \"debug_name\": \"b\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638187200555641996,
+                \"debug_name\": \"a\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 940060015955306962,
+          \"debug_name\": \"rename_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 5124477032042102868,
+            \"debug_name\": \"prev_a\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638190499090526629,
+                \"debug_name\": \"b\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 10451117352454336008,
+          \"debug_name\": \"felt252_sub_1\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638194897137039473,
+                \"debug_name\": \"n\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638194897137039473,
+                \"debug_name\": \"n\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7931306963920539685,
+          \"debug_name\": \"store_temp_rc\"
+        },
+        \"args\": [
+          {
+            \"id\": 638478738777676098,
+            \"debug_name\": \"rc\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 638478738777676098,
+                \"debug_name\": \"rc\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7943736942875005115,
+          \"debug_name\": \"store_temp_gb\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638187200555641996,
+            \"debug_name\": \"a\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638187200555641996,
+                \"debug_name\": \"a\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638190499090526629,
+            \"debug_name\": \"b\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 12638190499090526629,
+                \"debug_name\": \"b\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 16940139219101328589,
+          \"debug_name\": \"jump\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": {
+              \"Statement\": 18
+            },
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 3328301606880823183,
+          \"debug_name\": \"branch_align\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 6741348721511978627,
+          \"debug_name\": \"felt252_drop\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638187200555641996,
+            \"debug_name\": \"a\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 6741348721511978627,
+          \"debug_name\": \"felt252_drop\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638190499090526629,
+            \"debug_name\": \"b\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 6741348721511978627,
+          \"debug_name\": \"felt252_drop\"
+        },
+        \"args\": [
+          {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": []
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7931306963920539685,
+          \"debug_name\": \"store_temp_rc\"
+        },
+        \"args\": [
+          {
+            \"id\": 638478738777676098,
+            \"debug_name\": \"rc\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 638478738777676098,
+                \"debug_name\": \"rc\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 17829783910969655620,
+          \"debug_name\": \"redeposit_gas\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 7943736942875005115,
+          \"debug_name\": \"store_temp_gb\"
+        },
+        \"args\": [
+          {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 618457731543555724,
+                \"debug_name\": \"gb\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 3075775707538119114,
+          \"debug_name\": \"felt252_const_minus_1\"
+        },
+        \"args\": [],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 14050392017135853004,
+                \"debug_name\": \"err\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Invocation\": {
+        \"libfunc_id\": {
+          \"id\": 14115798396771957644,
+          \"debug_name\": \"store_temp_felt252\"
+        },
+        \"args\": [
+          {
+            \"id\": 14050392017135853004,
+            \"debug_name\": \"err\"
+          }
+        ],
+        \"branches\": [
+          {
+            \"target\": \"Fallthrough\",
+            \"results\": [
+              {
+                \"id\": 14050392017135853004,
+                \"debug_name\": \"err\"
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      \"Return\": [
+        {
+          \"id\": 638478738777676098,
+          \"debug_name\": \"rc\"
+        },
+        {
+          \"id\": 618457731543555724,
+          \"debug_name\": \"gb\"
+        },
+        {
+          \"id\": 14050392017135853004,
+          \"debug_name\": \"err\"
+        }
+      ]
+    }
+  ],
+  \"funcs\": [
+    {
+      \"id\": {
+        \"id\": 2313213558037562915,
+        \"debug_name\": \"Fibonacci\"
+      },
+      \"signature\": {
+        \"param_types\": [
+          {
+            \"id\": 5158587525321846130,
+            \"debug_name\": \"RangeCheck\"
+          },
+          {
+            \"id\": 8338741463261264245,
+            \"debug_name\": \"GasBuiltin\"
+          },
+          {
+            \"id\": 18197987107266074389,
+            \"debug_name\": \"felt252\"
+          }
+        ],
+        \"ret_types\": [
+          {
+            \"id\": 5158587525321846130,
+            \"debug_name\": \"RangeCheck\"
+          },
+          {
+            \"id\": 8338741463261264245,
+            \"debug_name\": \"GasBuiltin\"
+          },
+          {
+            \"id\": 18197987107266074389,
+            \"debug_name\": \"felt252\"
+          }
+        ]
+      },
+      \"params\": [
+        {
+          \"id\": {
+            \"id\": 638478738777676098,
+            \"debug_name\": \"rc\"
+          },
+          \"ty\": {
+            \"id\": 5158587525321846130,
+            \"debug_name\": \"RangeCheck\"
+          }
+        },
+        {
+          \"id\": {
+            \"id\": 618457731543555724,
+            \"debug_name\": \"gb\"
+          },
+          \"ty\": {
+            \"id\": 8338741463261264245,
+            \"debug_name\": \"GasBuiltin\"
+          }
+        },
+        {
+          \"id\": {
+            \"id\": 12638194897137039473,
+            \"debug_name\": \"n\"
+          },
+          \"ty\": {
+            \"id\": 18197987107266074389,
+            \"debug_name\": \"felt252\"
+          }
+        }
+      ],
+      \"entry_point\": 0
+    }
+  ]
+}"
+
+def foo :=
+  match Lean.Json.parse fib_jumps_input with
+  | .ok j => Sierra.parseJson j
+  | .error e => throwError e
+
+#eval foo