nautechsystems/nautilus_trader · error

failed to mint Lighter auth token: {e}

Error message

failed to mint Lighter auth token: {e}

What it means

This wraps any failure returned by the underlying build_auth_token signing routine (private key handling, Schnorr signing, serialization) into an anyhow error prefixed with 'failed to mint Lighter auth token'. It is a wrapper, so the root cause is in the inner error's Display output.

Source

Thrown at crates/adapters/lighter/src/signing/auth_token.rs:136

) -> anyhow::Result<SecretString> {
    let now = SystemTime::now()
        .duration_since(UNIX_EPOCH)
        .map_err(|_| anyhow::anyhow!("system clock is before UNIX epoch"))?
        .as_secs();
    let now_i64 = i64::try_from(now)
        .map_err(|_| anyhow::anyhow!("system clock overflowed when converting to i64"))?;
    let deadline = now_i64
        .checked_add(DEFAULT_AUTH_TOKEN_TTL_SECS)
        .ok_or_else(|| anyhow::anyhow!("deadline computation overflowed"))?;
    let sk = credential.private_key()?;
    build_auth_token(
        deadline,
        credential.account_index(),
        credential.api_key_index(),
        &sk,
        fresh_k(),
    )
    .map_err(|e| anyhow::anyhow!("failed to mint Lighter auth token: {e}"))
}

/// Draws a fresh canonical [`Scalar`] from the thread-local CSPRNG suitable
/// for the per-signature `k` nonce.
///
/// The Schnorr binding requires `k` to be drawn from a cryptographic RNG and
/// used at most once per signature; see [`PrivateKey::sign`] for the full
/// contract. The 40-byte draw is reduced modulo the curve order, so the
/// returned scalar is always canonical.
#[must_use]
pub fn fresh_k() -> Scalar {
    let mut bytes = [0u8; SCALAR_BYTES];
    rand::rng().fill(&mut bytes[..]);
    Scalar::from_le_bytes_reduce(bytes)
}

/// Build a Lighter auth token using the system clock as the `now` reference.
///

View on GitHub (pinned to 18893faf8b)

Solutions

1. Read the inner `{e}` message in the full error chain to find the real cause
2. Verify the credential's private key is a valid, correctly formatted key for the Lighter signer
3. Re-export or regenerate the API key and update credentials
4. Check for recent dependency upgrades that changed the signing API

Example fix

// before: opaque wrapper only
.map_err(|e| anyhow::anyhow!("failed to mint Lighter auth token: {e}"))
// after: caller-side, surface the chain
if let Err(e) = build_auth_token_for(&credential).await {
    tracing::error!("auth token mint failed: {e:#}");
    return Err(e);
}

if credential.private_key().is_err() {
    return Err(anyhow!("credential private key unavailable/invalid; fix before minting"));
}

fn credential_ready(c: &Credential) -> bool { c.private_key().is_ok() }

match mint_auth_token(&credential) {
    Ok(t) => t,
    Err(e) => {
        tracing::error!("token mint failed: {e:#}"); // {:#} prints the root cause
        return Err(e);
    }
}

When it happens

Trigger: Any of the token-minting call sites (apply_referral_attribution, is_maker_only_api_key, spawn_ws_consumer, generate_order_status_reports, paginate_fill_reports) when the private key is invalid/unreadable or the signing/serialization step inside build_auth_token fails.

Common situations: Corrupted or malformed API private key (wrong format, whitespace, non-hex), key file permissions, key type not supported by the signer, upstream signing crate returning an error after a version bump.

Related errors

• Failed to decode API secret: {e}
• no Lighter L2 credentials in env
• Redis config error: username supplied without password. Eith
• Invalid Betfair credentials: username provided but password
• Invalid Betfair credentials: password or app key provided bu

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/395eb8c9208272ba. Report an issue: GitHub.