Pancake vs Polygon.io flat files
Polygon.io flat files provide US equities, options, and crypto OHLCV data. Pancake is a prediction-market backtester. They are data provider vs backtesting platform.
At a glance
| Capability | Pancake | Polygon.io flat files |
|---|---|---|
| Open-source engine | ✓ Apache-2.0 (batter, Python) | ✗ proprietary data platform |
| Prediction-market native | ✓ Polymarket, Kalshi, binary outcomes | ✗ equities, options, crypto OHLCV only |
| Backtesting engine | ✓ batter runner with P&L + risk metrics | ✗ data provider only — no backtesting engine |
| Verification boundary doctrine | ✓ explicit 3-tuple in every receipt | ✗ data quality SLA only |
| Agent-callable MCP surface | ✓ 6-tool surface (v1.3) | ✗ REST data API only |
| Receipt URLs with byte-stable hashes | ✓ /r/<short_id> | ✗ not applicable (data provider) |
| US equities + options data | ✗ prediction markets only | ✓ full US tape, options chain, crypto aggregates |
| S3-style flat file download | ✗ | ✓ bulk download via Polygon S3 flat files |
What's different
Polygon.io is a financial data infrastructure company. Its flat files product delivers bulk historical OHLCV data for US equities, options, indices, and crypto aggregates via an S3-compatible download API. Researchers download these files to build their own backtesting pipelines using LEAN, zipline, Backtrader, or custom engines.
Pancake is hosting infrastructure for AI-built trading strategies, not a data provider. It does not sell OHLCV data and has no flat file download. Pancake's canonical datasets are prediction-market resolution records — rows with a market link, decision time, resolution time, entry price, and resolved outcome. These are EvidenceDataset rows uploaded by the agent, not purchased from Pancake. The validated receipt is the artifact that travels with the strategy toward live execution (a v2-roadmap capability).
The conceptual gap: Polygon provides the raw material (OHLCV bars) that equity backtesting engines consume. Pancake provides the execution environment (runner + receipt + verification boundary) that agents use to validate prediction-market strategies and the hosting layer that carries those strategies forward. A researcher could theoretically use Polygon's crypto data as a feature column in a Pancake EvidenceDataset, but that is an unusual use case.
Methodology overlap
Both platforms document data provenance and quality. Polygon publishes data latency and tape feed sources. Pancake's provenance block records the source_urls, transformations, and rows_sha256 of each EvidenceDataset. Both treat data quality as a first-class concern rather than a footnote.
When to use each
When to use Pancake
Use Pancake when your strategy trades prediction-market binary outcomes and you want a structured, agent-verifiable receipt. Pancake is the right tool when the evidence is assembled by an LLM agent from public data sources and you need a reproducible audit trail.
When to use Polygon.io flat files
Use Polygon.io flat files when you need bulk US equities, options, or crypto OHLCV data for building or training a model on your own infrastructure. Polygon is the right data provider for institutional-scale backtesting pipelines.
Citation
Polygon.io is a financial data platform providing market data APIs and bulk flat file downloads. polygon.io. Pancake comparison: usepancake.com/compare/pancake-vs-polygon-flat-files