Getting started

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hedera_ex is a native Elixir SDK for the Hedera network — no NIFs, no Java/Go sidecar. It builds and signs Hedera transactions, talks gRPC to consensus nodes over HTTP/2, and reads the mirror node.

Install

# mix.exs
def deps do
  [{:hedera_ex, "~> 0.7"}]
end

Keys

Hedera accounts use Ed25519 or ECDSA secp256k1 keys. Generate or load one:

alias Hedera.PrivateKey

key = PrivateKey.generate_ed25519()
# or from a hex string (0x optional):
key = PrivateKey.from_string_ecdsa(System.fetch_env!("OPERATOR_KEY"))

pub = PrivateKey.public_key(key)

Private keys are redacted in inspect/logs (#Hedera.PrivateKey<ecdsa_secp256k1 [redacted]>) — they never leak through a crash dump or Logger. See the Cryptography guide for the signing conventions.

A client

A client bundles the operator (the account that pays fees) and the node address book. testnet/2 uses the built-in testnet nodes with cross-node retry:

alias Hedera.{AccountId, Client, PrivateKey}

operator_id  = AccountId.parse("0.0.8260469")
operator_key = PrivateKey.from_string_ecdsa(System.fetch_env!("OPERATOR_KEY"))

client = Client.testnet(operator_id, operator_key)

Your first transaction

Submit a message to a Consensus Service topic and wait for its receipt:

alias Hedera.{Client, Receipt, TopicId}

{:ok, result} = Client.submit_message(client, TopicId.parse("0.0.9339331"), "hello hedera")
result.precheck_code   #=> 0  (the node accepted it)
result.ok?             #=> true

{:ok, receipt} = Client.transaction_receipt(client, result.transaction_id)
Receipt.success?(receipt)          #=> true
receipt.topic_sequence_number      #=> e.g. 42

Every write returns {:ok, %{precheck_code: integer, ok?: boolean, transaction_id: TransactionId.t()}} or {:error, reason}. A precheck_code of 0 means the node accepted the transaction; the consensus result (SUCCESS / a failure code) is in the receipt, fetched separately.

Where next

  • Transactions — the full write surface (transfers, tokens, files, schedules, contracts, accounts) and multi-signature.
  • Queries — free and paid reads (balances, account info, read-only contract calls).
  • Ethereum (EIP-1559) — sign and relay Ethereum transactions.
  • Cryptography — key types, the Hedera ECDSA convention, signing and verification.