constant-time-testing

Measures timing side channels in cryptographic implementations by running them, using dudect for statistical analysis and Timecop over Valgrind for dynamic tracing. Covers the formal, symbolic, dynamic, and statistical tool categories and how to read a result. Use when testing whether a running implementation is constant-time, measuring timing variance on a compiled binary, or investigating a suspected timing attack. Not for statically inspecting compiler output — the constant-time-analysis plugin covers that.

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Run this command in your terminal. No account required — it auto-detects your AI tool and installs the skill file.

npx @skills-hub-ai/cli install trail-of-bits-constant-time-testing

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Claude Code

~/.claude/skills/<skill>/SKILL.md

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Install

One-click setup for your editor

Run in your project root

npx @skills-hub-ai/cli install trail-of-bits-constant-time-testing --target claude-code

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Frequently asked questions about constant-time-testing

What does the constant-time-testing skill do?

How do I install the constant-time-testing skill?

Run `npx @skills-hub-ai/cli install trail-of-bits-constant-time-testing` from your terminal. The CLI writes the SKILL.md to the correct location for your AI tool (e.g. ~/.claude/skills/trail-of-bits-constant-time-testing/ for Claude Code or ~/.cursor/skills/ for Cursor with --target cursor) and adds it to your project's .skills.json lockfile.

Which AI tools does constant-time-testing work with?

constant-time-testing runs in Claude Code. It follows the open Agent Skills standard (SKILL.md), so the same skill works in every supported tool without modification.

Is the constant-time-testing skill free?

Yes. Every skill on skills-hub.ai is free and open-source. There are no premium tiers, paywalls, or usage limits. You only pay for whatever AI assistant you're already using.

How do I use constant-time-testing after installing it?

In Claude Code, type `/trail-of-bits-constant-time-testing` (or whatever slash command the skill registers) and the AI follows the skill's instructions immediately. You can also reference it by name in natural language, your AI loads the skill into context when relevant.

Can I share the constant-time-testing skill with my team?

Yes. Commit your project's .skills.json lockfile and teammates run `npx @skills-hub-ai/cli install` (no args) to install every skill at the exact version you pinned. Organization-scoped installs work via skills-hub.ai organizations.