dependency

software dependency

An external package, library, or service that a piece of software relies on to function. Dependencies are managed through package managers (npm for JavaScript, pip for Python, Cargo for Rust). Managing dependencies includes tracking versions, updating for security patches, and handling conflicts when two dependencies require incompatible versions of a shared library (dependency hell).

When you'd see it: Engineering planning, security reviews, CI/CD pipeline configuration, open source audits.

Why it matters: Modern software depends heavily on open source libraries. Unmanaged dependencies become security vulnerabilities (CVE patches left unapplied) and operational fragility (breaking changes in upstream packages). Dependency management is a core engineering hygiene practice.

Common mistakes: Pinning dependencies to exact versions without a regular update strategy. Old pinned versions miss security patches. Unpinned versions risk unexpected breaking changes from upstream updates.

Related technical debt, CI/CD, version control, open source