Honest Backtest Engine VS Diffyn

Honest Backtest Engine's answer

Most backtesting tools are built to make a strategy look good. Honest Backtest Engine is built to do the opposite — to catch the strategy that only works on paper before you risk real money on it. Every run headlines out-of-sample results, charges real trading costs, deflates the Sharpe ratio for how many parameter combinations you tried, and Monte-Carlo stress-tests the outcome. It ends in a single believability score from 0 to 100, and it shows you the checks your strategy failed, not just the ones it passed. No other tool leads with the red marks.

Diffyn's answer:

Addresses workflow and change management on LLM prompts, provide teams with traceability and visualization of tests across multiple models, provide deeper understading into efficiency of these prompts.

Honest Backtest Engine's answer

Because it's designed to tell you the truth rather than flatter you. It models real commission, slippage and borrow costs, it's look-ahead-proof, and it produces a tamper-evident signed report anyone can verify without trusting you. It runs entirely on your own machine — your data and strategies never leave your computer. It's a one-time €149 purchase with every future version included, no subscription. And it comes with a guarantee: if it doesn't catch a backtest that was lying to you within 30 days, you get a full refund.

Diffyn's answer:

Diffyn is the platform that specializes on both change management and multi-model analysis.

Honest Backtest Engine's answer

Python, with pandas and NumPy for the backtesting engine and data handling. Reports and the local interface are rendered as HTML in the browser. Reports are cryptographically signed using Ed25519 so they can be independently verified. It runs as a self-contained local application on Windows, Mac and Linux.

Diffyn's answer:

React, Next.js, POSTGRESQL

Honest Backtest Engine's answer

Retail and independent algorithmic traders who build and backtest their own strategies — especially anyone who has watched a great-looking backtest lose money in live trading and wants to know whether an edge is real before funding an account. It suits people comfortable with concepts like Sharpe ratio, overfitting and out-of-sample testing, though the reports are written to be readable without a quant background.

Diffyn's answer:

Professionals incorporating LLMs or AI tools in their workflow and wants to keep track of changes and test their prompts.

Honest Backtest Engine's answer

It was built out of a common, painful experience: strategies that backtest beautifully and then quietly lose money live. That gap is almost always caused by overfitting, ignored costs, look-ahead bias, or a single lucky run mistaken for an edge — and most backtesting tools do nothing to catch it. Honest Backtest Engine exists to run those checks automatically and to be honest about the result, even when the honest answer is "this edge probably isn't real."

Diffyn's answer:

I started working on Diffyn when I notice that prompting has become an essential part of work across many industries. While there are version control platofrms like github, they are not designed for just prompt management are can be overkill such applications, it is also not integrated natively with various LLMs and relevant tools for users to validate ideas and visualise results properly.