nconf
Hierarchical configuration manager for Node.js. Merges configuration from multiple sources in priority order: command-line arguments → environment variables → config files → defaults. Part of the Flatiron ecosystem. Provider-based architecture allows adding custom configuration sources (Redis, etcd, etc.).
Score Breakdown
⚙ Agent Friendliness
🔒 Security
Local configuration library in maintenance mode. No secret masking. Sensitive values stored in plain JS objects. Dependency hygiene may lag due to maintenance-mode status.
⚡ Reliability
Best When
You need simple hierarchical configuration merging from multiple sources in a Node.js project, especially when working in the older Flatiron/Express ecosystem.
Avoid When
Starting a new project — nconf is in maintenance mode. Use convict for schema validation or envalid for TypeScript-first configuration.
Use Cases
- • Layer configuration from CLI args, env vars, and JSON files with automatic priority ordering for Node.js agent services
- • Centralize multi-source configuration in a single nconf instance accessible throughout an agent application
- • Override configuration values at different granularities (deployment env vars override file defaults) for agent deployments
- • Access nested configuration values with namespace separator (nconf.get('db:host')) without manual parsing
- • Persist runtime configuration changes back to a JSON file with nconf.save() for agent state management
Not For
- • TypeScript-typed configuration — nconf has no TypeScript generics; use zod or convict for typed config
- • Schema validation — nconf has no validation layer; values are accepted as-is without type checking
- • New projects — nconf is in maintenance mode; consider convict or envalid for new development
Interface
Authentication
Local configuration library — no authentication required.
Pricing
MIT license. Maintenance-mode project; actively used but not actively developed.
Agent Metadata
Known Gotchas
- ⚠ nconf is in maintenance mode — new projects should use convict or envalid; existing code should be gradually migrated
- ⚠ nconf.get() returns undefined for missing keys without any error — agents must defensively check all config values or use defaults
- ⚠ Namespace separator ':' in keys (nconf.get('db:host')) only works for hierarchical JSON file config — flat env vars need explicit mapping
- ⚠ nconf.set() and nconf.save() write to in-memory or file stores — changes to memory store are not automatically persisted without calling save()
- ⚠ No type coercion — environment variables are always strings; agents must manually parse booleans (nconf.get('DEBUG') === 'true') and numbers
- ⚠ Provider ordering matters but is set programmatically — nconf.argv() must be called before nconf.env() before nconf.file() to get correct priority; call order defines override chain
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for nconf.
Scores are editorial opinions as of 2026-03-06.