01BEFORE THE TEST
“I want a long-term core portfolio with less severe drawdowns.”
STRUCTURING IDEA…VTI 60%BND 30%GLD 10%
Idea Builder
Turn an ordinary-language investment idea into explicit, testable assumptions.
PORTFOLIO BACKTEST / ASSUMPTION LAB
Backtest, compare, and monitoryour portfolio in one place.
See how your portfolio would have performed, compare alternatives side by side, and track allocation drift over time.
No coding · No brokerage connection · No investment recommendations
ONE CORE / SIX SUPPORTING TOOLS
Every Tool You Need to Test, Compare, and
Monitor Your Portfolio.
Every tool adds context, evidence, or continuity to the comparison you are already working on.
02BEFORE THE TEST
DividendsReinvested✓
InflationIncluded✓
RebalancingAnnual✓
Data coverageExtended index✓
Assumption Inspector
See what the backtest assumes before the result has a chance to persuade you.
03UNDERSTAND
VTI VS 70/30 PATH
Difference Breakdown
See when two backtests diverged and which assets contributed to the difference.
04ORGANIZE
v1.0Base allocationNOW
v1.1Added 10% gold4M
v1.2Annual rebalance8M
Comparison Timeline
Track every change, rationale, and backtest result in one versioned comparison.
05AFTER THE TEST
RESULT CONSISTENCY82APR
→RESULT CONSISTENCY71JUL
One assumption weakened with new data.
Conclusion Monitor
Re-run saved comparisons and notify you when the original result weakens or reverses.
06SHARE & VERIFY
RESILIENT CORECOMPARISON REPORT / 07.2026
DATA v26.07ENGINE 0.8.4VERIFIED
Reproducible Report
Share the result together with its data version, rules, assumptions, and known limitations.
CONTINUOUS REVIEW
Markets change.Your conclusions
can change
with them.
Saved comparisons are re-evaluated as new data becomes available. Instead of another price alert, see whether the reasoning behind your portfolio still holds.
- Original advantage still exists
- The result has become less consistent
- An assumption is being challenged
- Portfolio has drifted from its rules
MONITORED PORTFOLIO / 04LAST RUN · JUL 28, 2026
PORTFOLIO
CONDITIONALGold as a drawdown buffer
60% VTI · 30% BND · 10% GLD
RESULT CONSISTENCY71 / 100
JANFEBMARAPRMAYJUNJUL
01
CONCLUSION UPDATE
Drawdown protection remains visible, but the advantage narrowed from 6.4 to 4.9 points after the latest data update.
02
ASSUMPTION CHECK
The result remains sensitive to the selected start year.
METHODOLOGY
Every result should be explainable and reproducible.
A backtest is only as credible as the assumptions underneath it. Every comparison records the details needed to understand what was actually tested.
01
Data sources and update dates
VERIFIED02
Asset and index substitutions
VERIFIED03
Dividend, inflation, and cost treatment
VERIFIED04
Contribution and rebalancing rules
VERIFIED05
Calculation engine version
VERIFIED06
Known limitations and data gaps
VERIFIEDCREATE YOUR FIRST COMPARISON
Which portfolio configuration holds up best under your criteria?
TRY AN EXAMPLE
FEATURED BACKTESTS
Start with a portfolio investors already search for.
Each example opens directly to a historical result, its disclosed rule, and a Workspace starting point.
FEATURED / 01Magnificent 7 Backtest
Equal-weight mega-cap basket vs a broad US equity reference.
Open historical result →FEATURED / 02Golden Butterfly vs Permanent
Two defensive multi-asset allocations, compared over the same window.
Open historical result →FEATURED / 0360/40 vs All Weather
Compare a traditional stock–bond allocation with a disclosed regime-diversified ETF proxy.
Open historical result →More results: FAANG vs Magnificent 7 · Golden Butterfly · Permanent Portfolio · View all backtests →