Air-gapped search: full-text search with no internet connection

Stretchy installs and runs on networks with no internet access. It has no call-home, no cloud license check and no external dependencies at runtime. That makes it usable on classified, industrial and regulated networks.

Who needs air-gapped search

Defense organizations, intelligence agencies, industrial SCADA networks, healthcare providers, and sovereign research laboratories handle sensitive data that can never touch the public internet. Stretchy delivers high-performance BM25 keyword search, document extraction, and anomaly detection entirely within physical isolation.

Security model

Stretchy's air-gapped security model enforces three core principles:
1. Zero Telemetry Egress: The software contains no remote telemetry, crash reporting, or external DNS lookups.
2. Asymmetric Cryptographic Licensing: Licenses are validated using Ed25519 public key cryptography locally without network handshakes.
3. Anti-Tamper Monotonic Clock Watermark: Encrypted local state prevents system clock manipulation past license expiration boundaries.

System requirements

Stretchy runs on standard commercial off-the-shelf (COTS) x86_64 and ARM64 hardware:
• CPU: Minimum 1 vCPU (2+ cores recommended for concurrent workloads)
• RAM: 512 MB minimum (<150 MB active heap)
• Storage: Standard SSD or NVMe storage for Lucene inverted index files
• Operating System: Red Hat Enterprise Linux, Rocky Linux, Ubuntu, Debian, Alpine Linux, or Windows Server.

Common questions

Does Stretchy ever contact the internet?

Never. The core server has no network dependencies outside its local loopback and bind address. All licensing and search operations occur 100% offline.

How are updates delivered to an air-gapped system?

Updates are provided as self-contained Docker tar archives or standalone JAR bundles with cryptographic checksums, designed for transfer via approved data diodes or optical media.