x-forecast · paper portfolio
Credibility / Audit trail · Beta

Provenance (Point-in-Time)

On every trading day this site freezes its complete published state (NAV / regime / CMA / decisions) into one append-only record, with a content hash (data_sha) and commit hash (git_sha). This is the cryptographic answer to "how do you prove that, looking back at a given day, you only saw the information available that day" — and the prerequisite for honest forecast scoring later.

Verifiability commitments

  • ✓Never force-push to rewrite history — NAV, decisions and rebalances are append-only, never silently edited (git history is the audit trail).
  • ✓Daily updates are auto-committed by GitHub Actions — the server-side push timestamp is hard to forge, serving as publish-time proof for each signal.
  • ✓Restatements are logged, not hidden — e.g. the INC-2026-001 price-scale incident was publicly restated with the prior version preserved; bad history is never erased.
  • ✓OpenTimestamps is wired into the daily job: each trading day the hash of vintages.jsonl is anchored to the Bitcoin blockchain (proofs in ots-proofs/), giving a third-party timestamp independent of git/GitHub; verify with `ots verify`.

Ledger status

Frozen snapshots
1
Range
2026-06-17 → 2026-06-17
Latest NAV
2026-06-15 · 104.0463
Latest snapshot (2026-06-17):
US regime Q4 (2026-04) · CN regime Q2 (2026-04) · decisions 0/1 closed
data_sha: 04a9f765a6b50c80a56e5c7d0cb63991c82f87ba42227a9e2584c801620b2e39
git_sha: 726164c0f85fbddc6587fc748a0fdb9e9db89a27

How to verify independently

The verification method is fully specified below. The repository is private during the author’s job search and can be opened to reviewers / employers on request — with repo access, anyone can recompute a row’s data_sha and check that commit’s server-side timestamp on GitHub: 

git clone https://github.com/zx20030501/x-forecast
# 重算最新一行的内容哈希 (应等于 data_sha 字段)
python scripts/snapshot_vintage.py     # idempotent: no append if unchanged
# 查某次日更提交的服务器侧时间 (发布时间证明)
git log --format='%H %cI' -- data/vintages.jsonl
# 用比特币区块链独立核验某日存证 (独立于 git/GitHub)
ots verify ots-proofs/vintages-YYYYMMDD.jsonl.ots

Ledger file: data/vintages.jsonl · generated by: scripts/snapshot_vintage.py

Point-in-time / vintage discipline is the credibility bedrock of institutions (JPMaQS, Research Affiliates’ forecast scorecard). This ledger grows each trading day; once enough samples accumulate it will drive forecast scoring on /track-record.