Skip to main content Build robust backtesting systems for trading strategies with proper handling of look-ahead bias, survivorship bias, and transaction costs. Use when developing trading algorithms, validating strategies, or building backtesting infrastructure.
npx skills add wshobson/agents --skill backtesting-frameworks agents claude claude-code subagents anthropic automation
Backtesting Frameworks
Build robust, production-grade backtesting systems that avoid common pitfalls and produce reliable strategy performance estimates.
When to Use This Skill
Developing trading strategy backtests
Building backtesting infrastructure
Validating strategy performance
Avoiding common backtesting biases
Implementing walk-forward analysis
Comparing strategy alternatives
Core Concepts
1. Backtesting Biases
Bias Description Mitigation Look-ahead Using future information Point-in-time data Survivorship Only testing on survivors Use delisted securities Overfitting Curve-fitting to history Out-of-sample testing Selection Cherry-picking strategies Pre-registration Transaction Ignoring trading costs Realistic cost models
2. Proper Backtest Structure Historical Data
│
▼
┌─────────────────────────────────────────┐
│ Training Set │
│ (Strategy Development & Optimization) │
└─────────────────────────────────────────┘
│
▼
┌─────────────────────────────────────────┐
│ Validation Set │
│ (Parameter Selection, No Peeking) │
└─────────────────────────────────────────┘
│
▼
┌─────────────────────────────────────────┐
│ Test Set │
│ (Final Performance Evaluation) │
└─────────────────────────────────────────┘
3. Walk-Forward Analysis Window 1: [Train──────][Test]
Window 2: [Train──────][Test]
Window 3: [Train──────][Test]
Window 4: [Train──────][Test]
─────▶ Time
Detailed worked examples and patterns Detailed sections (starting with ## Implementation Patterns) live in references/details.md. Read that file when the navigation summary above is insufficient.
Best Practices
Do's
Use point-in-time data - Avoid look-ahead bias
Include transaction costs - Realistic estimates
Test out-of-sample - Always reserve data
Use walk-forward - Not just train/test
Monte Carlo analysis - Understand uncertainty
Don'ts
Don't overfit - Limit parameters
Don't ignore survivorship - Include delisted
Don't use adjusted data carelessly - Understand adjustments
Don't optimize on full history - Reserve test set
Don't ignore capacity - Market impact matters
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Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).