Signer

The Signer module defines Signer—the standard interface used throughout Colibri for transaction and authorization signing. By defining a clear interface, anyone can build custom signers and key handling tools that integrate seamlessly with Colibri's pipelines and processes.

Signer Interface

All signers in Colibri implement the Signer interface:

type Signer = {
  /** Returns the public key for this signer */
  publicKey(): Ed25519PublicKey;

  /** Signs arbitrary data and returns the signature as a Buffer */
  sign(data: Buffer): Buffer;

  /** Signs a transaction and returns its XDR string */
  signTransaction(
    tx: Transaction | FeeBumpTransaction
  ): Promise<TransactionXDRBase64> | TransactionXDRBase64;

  /** Signs a Soroban authorization entry */
  signSorobanAuthEntry(
    authEntry: xdr.SorobanAuthorizationEntry,
    validUntilLedgerSeq: number,
    networkPassphrase: string
  ): Promise<xdr.SorobanAuthorizationEntry>;

  /** Returns true if this signer can sign for the given target */
  signsFor(target: Ed25519PublicKey | ContractId): boolean;
};

Using Signers

Pass signers to pipelines via the TransactionConfig:

import { PIPE_InvokeContract, NetworkConfig } from "@colibri/core";

const pipeline = PIPE_InvokeContract.create({ networkConfig });
const result = await pipeline.run({
  operations: [...],
  config: {
    source: signer.publicKey(),
    fee: "100000",
    signers: [signer], // Signer handles both TX and auth signing
  },
});

Multiple Signers

For multi-signature transactions, pass multiple signers:

config: {
  source: signer1.publicKey(),
  fee: "100000",
  signers: [signer1, signer2], // Both signers will be used
}

Implementing Custom Signers

For hardware wallets, custodial services, or custom signing flows, implement the Signer interface:

class CustomSigner implements Signer {
  publicKey(): Ed25519PublicKey {
    // Return the public key
  }

  sign(data: Buffer): Buffer {
    // Sign arbitrary data
  }

  signTransaction(tx: Transaction | FeeBumpTransaction): TransactionXDRBase64 {
    // Sign and return XDR
  }

  async signSorobanAuthEntry(
    entry: xdr.SorobanAuthorizationEntry,
    validUntil: number,
    passphrase: string
  ): Promise<xdr.SorobanAuthorizationEntry> {
    // Sign Soroban auth entry
  }

  signsFor(target: Ed25519PublicKey | ContractId): boolean {
    // Return true if this signer can sign for the target
  }
}

Available Signers

Signer	Description
LocalSigner	Simple in-memory signer for convenience

Next Steps

• LocalSigner — Built-in in-memory signer

• TransactionConfig — Configuration that includes signers

• Pipelines — Use signers in transaction workflows