ECC is a toolkit that organizes and improves how coding agents work through skills, memory, security checks, research practices, and related extensions. It is for developers using agents such as Claude Code, Codex, OpenCode, and Cursor.
Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/affaan-m/ECCnpx agentmods add skills/affaan-m/ecc/bun-runtimeWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/affaan-m/ecc/bun-runtime)<a href="https://agentmods.dev/skills/affaan-m/ecc/bun-runtime"><img src="https://agentmods.dev/badge/skills/affaan-m/ecc/bun-runtime/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/affaan-m/ecc/bun-runtime"><img src="https://agentmods.dev/badge/skills/affaan-m/ecc/bun-runtime.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Privilege Escalation · line 45 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00034 | $0.01415 |
| Opus 5.5 | $0.00014 | $0.00566 |
| Sonnet 5.5 | $0.00007 | $0.00283 |
| Haiku 4.5 | $0.00003 | $0.00142 |
Grade A, and why
bun-runtime scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
fetch(req) { Copies of this mod
8 near-identical copies found in the catalogue:
- bun-runtime — 100% identical, 23 lines differ
- bun-runtime — 100% identical, 22 lines differ
- bun-runtime — 100% identical, 23 lines differ
- bun-runtime — 100% identical, 23 lines differ
- bun-runtime — 100% identical, 24 lines differ
- bun-runtime — 100% identical, 23 lines differ
- bun-runtime — 100% identical, 23 lines differ
- bun-runtime — 100% identical, 24 lines differ
How it starts
The opening of the file, as written. The whole thing — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Bun Runtime
Bun is a fast all-in-one JavaScript runtime and toolkit: runtime, package manager, bundler, and test runner.
When to Use
- Prefer Bun for: new JS/TS projects, scripts where install/run speed matters, Vercel deployments with Bun runtime, and when you want a single toolchain (run + install + test + build).
- Prefer Node for: maximum ecosystem compatibility, legacy tooling that assumes Node, or when a dependency has known Bun issues.
Use when: adopting Bun, migrating from Node, writing or debugging Bun scripts/tests, or configuring Bun on Vercel or other platforms.
How It Works
- Version baseline: guidance below targets Bun 1.4.x. Check the actual version with
bun --versionbefore relying on flag names, since CLI flags can change between releases. - Runtime: Drop-in Node-compatible runtime, built on JavaScriptCore. As of Bun 1.4 the runtime itself is implemented in Rust (migrated from Zig). Not 100% Node-compatible — some native addons, less-common
node:internal APIs, and packages that depend on Node-specific internals can still fail; verify before depending on it in production. - Package manager: Bun includes a package manager; installation performance depends on the project, network conditions, and cache state. Lockfile is
bun.lock(text) by default in current Bun; older versions usedbun.lockb(binary) — Bun still reads that format for migration, but new projects should usebun.lock. - Bundler: Built-in bundler and transpiler for apps and libraries.
- Test runner: Built-in
bun testwith a Jest-like API.
Migration from Node: Replace node script.js with bun run script.js or bun script.js. Run bun install in place of npm install; most packages work. Use bun run for npm scripts; bun x for npx-style one-off runs. Node built-ins are supported; prefer Bun APIs where they exist for better performance.
Package and workspace commands: bun add <pkg> / bun remove <pkg> / bun update [pkg] manage dependencies; bun outdated lists stale deps. bun pm ls lists project dependencies and resolved versions using the lockfile; --all includes transitive dependencies. It is not an integrity check of installed file contents. bun audit queries registry advisories using package names and versions from bun.lock; it does not modify package.json, bun.lock, or node_modules. Review approved destinations before sending private package metadata. Packages whose scoped registry lacks an advisory endpoint are skipped and do not affect the exit code. bun audit fix upgrades and installs dependencies, changing the lockfile and installed packages and sometimes direct version pins; review it as a modifying install operation, including applicable lifecycle scripts. bun dedupe collapses duplicate installs, and bun prune removes packages no longer referenced. Monorepos use a root workspaces array in package.json (same convention as npm/yarn); run a script in one workspace with bun run --filter <pkg-name> <script>.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 12d ago Changed · +9 lines 27c101ca2547
- 1mo ago Changed · +1 lines b93720b74ea9
- 1mo ago First seen · 84 lines · 34 tokens per session scan A 7b66f97f5057
bun-runtime is a skill published in the GitHub repository affaan-m/ECC (285,716 stars, last pushed yesterday), licensed MIT. It adds 34 tokens to every session and 1,415 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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