EngFlow Remote Caching vs FosterStack
EngFlow Remote Caching
engflow.comFosterStack
fosterstack.comSide by side
| Figure | EngFlow Remote Caching | FosterStack |
|---|---|---|
| Price from | Free | $41.58/mo |
| Free plan | Yes | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | — |
| Windows | Yes | — |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | Yes |
| Plans published | 2 | 4 |
| Spec score · Build Cache Software | 7.8 (#12) | 7.9 (#10) |
| Authentication | The pricing comparison lists HTTP basic authentication and mTLS for Free, with GCP IAM, Google OAuth, SAML, and custom options added for Enterprise. | It supports HTTP Basic Auth over TLS, with constant-time credential comparison and no credential logging. |
| Compliance | EngFlow says its solutions receive regular third-party audits against the five SOC 2 principles. | FosterStack says it is not FedRAMP or CMMC compliant; its published evidence and validated crypto are intended to support a customer's compliance program. |
| Deployment | The pricing page lists Free as self-hosted and Enterprise as self-hosted or managed, with deployment options that include bare metal, AWS, GCP, Kubernetes, and OpenStack for Free, plus Azure, MacStadium, and Orka for Enterprise. | The product is self-hosted and can be run from a Docker image or as a static binary. |
| Security | EngFlow says builds run in isolated environments with encryption and, by default, dedicated infrastructure. | The core is MIT-licensed, releases include signed artifacts and SLSA provenance, and security patches are included in the free tier. |
| Support | The pricing page lists community support for Free and a dedicated engineer for Enterprise. | Bugs and questions can be reported through GitHub issues; the listed paid tiers describe email and priority support but are not yet available. |
Plans
In their own words
EngFlow Remote Caching
EngFlow Remote Caching is a remote cache service for reducing repeated builds and test reruns, developer workload, and compute costs. It uses gRPC, cache compression, and Build without the Bytes to limit latency and unnecessary data transfers. A layered cache keeps frequently requested data available, while the Build & Test UI reports cache hit rates, build time, and status in real time. The Free tier supports Bazel and provides in-cluster caching on one machine with 32 CPU cores, running Linux. Enterprise supports Bazel, Goma for Chromium, and Soong for AOSP, as well as in-cluster or external storage such as S3 and GCS. Free is self-hosted; Enterprise can be self-hosted or managed. The service is available for Linux, macOS, Windows, web, and API use. EngFlow says builds run in isolated, encrypted environments with dedicated infrastructure by default, and its solutions receive regular third-party audits against the five SOC 2 principles. Free costs nothing; Enterprise pricing is custom quote. A trial request form is available, with no duration stated.
FosterStack
FosterStack is a self-hosted remote build cache server intended as a replacement for Develocity Build Cache Node. It supports Gradle and the Apache Maven Build Cache Extension remote HTTP mode, although Maven acceptance coverage is in progress. Size-capped LRU eviction frees space for new entries. HTTP Basic Auth over TLS uses constant-time credential comparison, and credentials are not logged. Prometheus metrics and a read-only status page report hit rates and cache size against its cap. Deployment options are a Docker image or static binary; release binaries are available for Linux and macOS on amd64 and arm64. Windows is not built or planned. The MIT-licensed core has signed releases with SLSA provenance, and security patches are included in the free tier. The maker says the free core makes no outbound connections and collects no telemetry or usage data. FosterStack identifies the product as v0.1 and says nobody outside its own work is yet running it in a production build pipeline. The full self-hosted server is free. Team, Business, and Compliance plans are described but not yet available, with listed prices of $49.00 per month, $199.00 per month, and $499.00 per year, respectively.