Kaitai Struct parser for Bitcoin Transactions

btc.ksy.yaml

# Bitcoin Transaction
# Spec: https://en.bitcoin.it/wiki/Transaction
meta:
  id: btc_txn
  endian: le
  file-extension: txn
seq:
  # Bitcoin version, usually 1.
  - id: version
    type: u4
  # Number of inputs.
  - id: in_counter
    type: var_int
  # Input data.
  - id: inputs
    type: input
    repeat: expr
    repeat-expr: in_counter.value
  # Number of outputs.
  - id: out_counter
    type: var_int
  # Output data.
  - id: outputs
    type: output
    repeat: expr
    repeat-expr: out_counter.value
  # Lock time.
  - id: lock_time
    type: u4
types:
  # Variable length integer, as defined here:
  # https://en.bitcoin.it/wiki/Protocol_documentation#Variable_length_integer
  var_int:
    seq:
      - id: int1
        type: u1
      - id: int2
        type: u2
        if: int1 == 0xFD
      - id: int4
        type: u4
        if: int1 == 0xFE
      - id: int8
        type: u8
        if: int1 == 0xFF
    instances:
      value:
        value: int1 == 0xFD ? int2 : int1 == 0xFE ? int4 : int1 == 0xFF ? int8 : int1
  input:
    seq:
      - id: prev_txn_hash
        size: 32
      - id: prev_txn_out_idx
        type: u4
      - id: script_len
        type: var_int
      - id: script
        size: script_len.value
      - id: sequence_num
        type: u4
  output:
    seq:
      - id: val
        type: u8
      - id: txout_script_len
        type: var_int
      - id: txout_script
        size: txout_script_len.value

Why haven't you sent it to the official formats repo?