---
sidebar_position: 4
title: OpenTimestamps Integration
description: "How TrackForge submits Merkle root hash commitments to OpenTimestamps, records Bitcoin-anchored proof state, and reports pending versus confirmed status."
keywords:
  - OpenTimestamps integration
  - Bitcoin timestamp
  - OTS proof
  - Merkle root
  - hash commitment
---

# OpenTimestamps Integration

TrackForge uses OpenTimestamps (OTS) to create independently verifiable timestamp evidence for methodology hashes and evidence roots.

## What Is Submitted

TrackForge stores hashes as 64-character lowercase hexadecimal SHA-256 strings. For OTS submission, the implementation:

1. Validates that the value is a 64-character lowercase hex digest.
2. Decodes the hex string to 32 bytes with `bytes.fromhex(hash_hex)`.
3. Computes `SHA256(decoded_hash_bytes)`.
4. Submits that 32-byte commitment to OTS calendar servers.

This means the OTS commitment is a SHA-256 commitment of the decoded hash/root bytes. It is not the raw ASCII string of the Merkle root.

## Submission Flow

```mermaid
flowchart TB
    A["64-char hex hash"] --> B["Decode to 32 bytes"]
    B --> C["SHA-256 commitment"]
    C --> D["POST /digest to OTS calendar"]
    D --> E["Pending .ots proof"]
    E --> F["Upgrade / check confirmation"]
    F --> G["Confirmed or still pending"]
```

The proof bundle should include both the original hash value and the `.ots` proof file, so an independent verifier can reproduce the commitment and validate the timestamp.

## Proof States

| State | Meaning |
|---|---|
| `pending` | Calendar proof exists or submission is awaiting confirmation. |
| `confirmed` | Proof contains confirmed blockchain attestation. |
| `failed` | Submission or upgrade failed. |
| `not_submitted` | No OTS submission was made. |
| `local_only` | Local witness only; not a public blockchain confirmation. |

Certificate and verification pages must not blur pending, confirmed, failed, and local-only states.

## Calendar Servers

TrackForge submits to configured OTS calendar servers. Calendar availability is external to TrackForge; if calendars are unreachable, the system can preserve a local witness state so certification work is not silently blocked. That state must be labelled as local-only rather than confirmed.

## Verification Without TrackForge

To verify a confirmed proof:

1. Recompute the relevant evidence or methodology hash.
2. Decode the 64-character hash to bytes.
3. Compute the OTS commitment hash.
4. Verify the `.ots` file with a compliant OpenTimestamps verifier.
5. Confirm the verified commitment corresponds to the certificate's hash/root.

The certificate should provide enough information for this process without requiring access to TrackForge systems.