Silo

Spec sheet

Purpose

Silo is a self-hosted HTTP server that speaks the Gradle build cache protocol and replaces the end-of-life Gradle Remote Build Cache Node.Read 8 Oct 2026 · github.com

Deployment

Silo is distributed as a fat JAR and a multi-architecture Docker image for linux/amd64 and linux/arm64.Read 8 Oct 2026 · github.com

Security

The project says it has no phone-home telemetry or accounts and supports atomic writes with crash recovery.Read 8 Oct 2026 · github.com

Admin dashboard

Silo includes a single-page admin dashboard at /admin, and its live demo runs with simulated data without installation or a backend.Read 8 Oct 2026 · github.com

Authentication

Silo supports HTTP Basic and OIDC/Bearer authentication with read-only and read-write role mapping.Read 8 Oct 2026 · github.com

Cache management

It supports LRU eviction, TTL, byte and entry caps, and reserved free-space thresholds.Read 8 Oct 2026 · github.com

Current status

The project describes itself as alpha and says S3/GCS backends, compression, and replication remain open work.Read 8 Oct 2026 · github.com

Implementation

Silo is written in Kotlin using Ktor and requires JVM 21 or later.Read 8 Oct 2026 · github.com

Monitoring

Silo provides Prometheus metrics, JSON-structured logs, health and readiness endpoints, and a live stats stream.Read 8 Oct 2026 · chrisjenx.github.io

Protocol

It supports the Gradle HTTP build cache protocol methods GET, PUT, and HEAD.Read 8 Oct 2026 · github.com

Release integrity

The security policy says release artifacts are cosign-signed, the fat JAR has a SHA-256 checksum, and every release includes a CycloneDX SBOM.Read 8 Oct 2026 · github.com

Security support

Silo is pre-1.0, and only the latest v0.x release receives security fixes; the policy promises acknowledgement within 3 business days and initial assessment within 7 business days.Read 8 Oct 2026 · github.com

Storage

Filesystem storage is implemented, while S3 and GCS are listed as roadmap items.Read 8 Oct 2026 · github.com

Plans and prices

Every Silo plan and price →

Where Specifiction places it

• Build Cache Software#21 of 237.3