GravityKit
GravityKit ships weekly across a whole plugin suite, with an MCP server now part of the lineup.
Comparison · Infra & APIs
Firecracker vs LibreSpeed
A side-by-side editorial comparison of Firecracker and LibreSpeed — release velocity, themes, recent moves, and the top alternatives to consider.
Firecracker vs LibreSpeed: at a glance
What is Firecracker?
Firecracker's microVMs can now grow and shrink devices while running.
1.16.0 in June added developer-preview hotplug and hot-unplug for PCI virtio block, pmem and net devices on a live microVM, with the guest responsible for rescanning the bus and removing the device first since no notification mechanism exists yet. The same release added vsock Unix socket path overriding on snapshot restore, rate limiting for serial console output with a dropped-bytes metric, and per-callsite log rate limiting. 1.16.1 followed with a vsock fix for connections timing out after restore when a snapshot caught an in-flight TX descriptor. Earlier in the window, 1.15.0 added the VMClock device and Intel Granite Rapids support, and the April patches hardened the PCI transport against CVE-2026-5747.
What is LibreSpeed?
After a two-year redesign, LibreSpeed is adding tests instead of polishing pixels.
LibreSpeed is a self-hosted speed test that spent roughly two years landing a new frontend design, shipped it behind a feature switch, then promoted it to default in 6.0.0. With that out of the way, 6.2.0 turns to capability: a standalone connection-stability test with live latency charting, packet-loss tracking, alerts and CSV export, plus PWA metadata so the tool can be installed from a browser. Docker deployment has been reworked in parallel, including a port change and PHP limits that were silently rejecting default upload chunks.
Firecracker vs LibreSpeed: editorial side-by-side
Firecracker
0.0INFRA · APIS
Firecracker's microVMs can now grow and shrink devices while running.
◆ Current state
1.16.0 in June added developer-preview hotplug and hot-unplug for PCI virtio block, pmem and net devices on a live microVM, with the guest responsible for rescanning the bus and removing the device first since no notification mechanism exists yet. The same release added vsock Unix socket path overriding on snapshot restore, rate limiting for serial console output with a dropped-bytes metric, and per-callsite log rate limiting. 1.16.1 followed with a vsock fix for connections timing out after restore when a snapshot caught an in-flight TX descriptor. Earlier in the window, 1.15.0 added the VMClock device and Intel Granite Rapids support, and the April patches hardened the PCI transport against CVE-2026-5747.
◆ Where it's heading
The through-line is snapshots and the PCI transport maturing together. Firecracker's value has always been fast boot from a snapshot, and the recent fixes are all in the seams that opens up — TX descriptors in flight when a snapshot is taken, vsock paths that change on restore, virtio device state machines that must be validated the same way on PCI as on MMIO. Hotplug extends the same idea from restore-time to run-time: a microVM that can change shape is one you can keep rather than replace.
◆ Prediction
Hotplug shipped explicitly as a developer preview requiring manual guest bus rescans, so the stated gap is an automatic notification mechanism. That is the obvious next step before the feature leaves preview.
LibreSpeed
2.5INFRA · APIS
After a two-year redesign, LibreSpeed is adding tests instead of polishing pixels.
◆ Current state
LibreSpeed is a self-hosted speed test that spent roughly two years landing a new frontend design, shipped it behind a feature switch, then promoted it to default in 6.0.0. With that out of the way, 6.2.0 turns to capability: a standalone connection-stability test with live latency charting, packet-loss tracking, alerts and CSV export, plus PWA metadata so the tool can be installed from a browser. Docker deployment has been reworked in parallel, including a port change and PHP limits that were silently rejecting default upload chunks.
◆ Where it's heading
The redesign was the blocker; now that it is default, releases are moving outward — a second measurement mode, installability, better multi-server list handling. The Docker thread runs alongside and is where the breaking changes live: default port moved from 80 to 8080 in preparation for rootless operation, post_max_size raised to accept the tool's own 20 MiB chunks, Alpine base updated. Much of the recent throughput comes from outside contributors and automated agents rather than a single maintainer.
◆ Prediction
Expect the stability test to gain the configuration and server-side plumbing the main speed test already has, and the rootless-container work that the port change was preparation for to land next. Nothing in the entries suggests a change to the project's self-hosted, no-backend-dependency positioning.
Alternatives to Firecracker and LibreSpeed
Other Infra & APIs products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either Firecracker or LibreSpeed.
Nautobot
A security advisory cycle forced Nautobot to break its REST API on both supported branches at once.
Gatekeeper
Gatekeeper grew a package manager for policies — and a benchmark to prove they are not too slow.
GoCD
GoCD's changelog is one maintainer keeping a 2010s CI server running on current runtimes.
Incus
Incus settled its 7.0 LTS, then went straight back to a monthly feature cadence.
runc
runc now publishes an end-of-life calendar, and three branches shipped the same CVE fix in two days.
See all Firecracker alternatives → · See all LibreSpeed alternatives →
Recent activity from Firecracker and LibreSpeed
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 15d agoLibreSpeedStandalone connection-stability test and installable PWA support
- 1mo agoFirecrackerVsock timeout after snapshot restore, and jailer symlink revert
- 2mo agoFirecrackerFirecracker v1.16.0 ⚡
- 3mo agoLibreSpeedBugfix on classic design
- 3mo agoLibreSpeedNew design is main now
- 4mo agoFirecrackervirtio-rng entropy cap and PCI transport hardening (CVE-2026-5747)
- 4mo agoFirecrackerCVE-2026-5747 hardening on the 1.15 branch
- 4mo agoFirecrackerTCP SYN options length validation with MMDS enabled
- 5mo agoFirecrackerVMClock device and Intel Granite Rapids support
- 6mo agoLibreSpeedHotfix for SQLite database matching in the Docker entrypoint
- 7mo agoLibreSpeedPre-release puts the new design behind a feature switch
- 7mo agoLibreSpeedFinal 5.x release moves the Docker port to 8080
Frequently asked questions
What is the difference between Firecracker and LibreSpeed?
They serve adjacent needs but don't currently overlap on shipped themes. LibreSpeed is currently shipping more aggressively (velocity 2.5 vs 0.0), with 0 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is Firecracker better than LibreSpeed?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. LibreSpeed is currently shipping more aggressively (velocity 2.5 vs 0.0), with 0 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Infra & APIs products to evaluate alongside.
What are the best alternatives to Firecracker?
Top Firecracker alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "Firecracker alternatives" section above for the current picks, or visit /alternatives/firecracker for the full list with editorial commentary on each.
What are the best alternatives to LibreSpeed?
Top LibreSpeed alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "LibreSpeed alternatives" section above for the current picks, or visit /alternatives/librespeed for the full list with editorial commentary on each.