Fly.io
Fly.io runs AI agent sandboxes on hardware-isolated Linux VMs called Sprites that checkpoint automatically and bill by the second.
If you're building coding agents or running untrusted code and you're tired of bolting persistence onto sandboxes, Sprites solve the specific problem that costs you the most time: state that survives between runs. Machines give the deployment destination without a platform migration. The tradeoff is real — this is CLI-first infrastructure, not a managed serverless abstraction, so teams that want zero ops involvement should look elsewhere.
Verified 23h ago · liveness 76/100 · cite: rightaichoice.com/tools/fly-io
- AI agent builders who need persistent, hardware-isolated sandboxes with automatic checkpointing
- Teams running coding agents like Claude or Codex that must resume into the same filesystem
- Developers hosting MCP servers with persistent disk and egress policy
- Teams executing untrusted code in clean, disposable VMs with a fresh baseline per request
- Simple static websites that a shared host or CDN serves for less
- Teams that want a fully managed serverless abstraction where regions and VM presets never come up
- Non-technical users expecting a click-and-deploy GUI — the front door is the flyctl CLI
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Skip Fly.io if you want a fully managed serverless abstraction like AWS Lambda, need a flat monthly compute bill, or aren't comfortable with a CLI and infrastructure concepts — Sprites and Machines are developer-grade primitives.
Sprites bill by CPU-hour ($0.07) and memory-hour ($0.04375/GB) while awake, so a Sprite that never sleeps still costs money even when idle-triggered work isn't running.
Sprites and Machines are usage-metered, so the effective bill depends entirely on how much your workload actually runs — a solo developer running light agent workloads can start free and stay near $0, while a team running dozens of always-awake Sprites or the Performance Postgres tier at $1,922/mo is in enterprise cloud territory. Against AWS Lambda (function-level billing, more abstraction) Fly.io gives you full VMs; against a reserved EC2 instance ($30-300/mo range for comparable specs)
In short
Fly.io — Fly.io runs AI agent sandboxes on hardware-isolated Linux VMs called Sprites that checkpoint automatically and bill by the second. Best for AI agent builders who need persistent, hardware-isolated sandboxes with automatic checkpointing, Teams running coding agents like Claude or Codex that must resume into the same filesystem, Developers hosting MCP servers with persistent disk and egress policy. Free to start; paid plans from $0.039.
What's new in Fly.io
Checked yesterdayAcross the latest 3 updates: 3 feature updates.
Building Agents that Don't Break Themselves
Walkthrough of using Sprites as safe sandboxes for AI agents, showing how checkpointing and egress controls prevent accidental damage to hosts.
Code And Let Live
Introduces the `sprite create` command for running code instantly in a sandboxed Sprites environment.
Litestream VFS
Litestream adds a virtual filesystem for SQLite, enabling direct access to databases stored in S3 object storage.
What people actually say about Fly.io — is it worth it?
We ran a structured research pass across product reviews, community discussions, and post-purchase forum threads to surface the patterns vendors won't publish themselves. Below: the recurring strengths, the hidden costs people mention most, and the cohort that consistently regrets adopting this tool.
82 mentions across 5 sources (Hacker News, YouTube, Product Hunt, Bluesky, Lemmy) · researched Jul 26, 2026.
Average across the 5 sources that answered — each source counts once, not each post.
- +Global edge deployment with 18 regions for sub-100ms latency.
- +Hardware-virtualized Machines launch instantly and run only when needed.
- +Sprites sandboxes safely execute AI-generated code with checkpoint/restore.
- +Per-second billing for CPU and memory keeps costs low for sporadic workloads.
- +Private networking with granular routing enables secure multi-service setups.
- −Reliability issues with frequent outages reported by multiple users.
- −Sprites sandboxes were buggy early on, losing data and needing support.
- −CEO transition and pivot to AI create uncertainty about core platform.
- −Pricing considered high by some compared to alternatives.
- −New Sprites focus may divert resources from traditional PaaS features.
- • Outbound data transfer beyond free tier can add up
- • Sprites billing is separate and may increase costs for heavy AI workloads
- • NVMe storage and private networking may incur extra charges at scale
Viability Score
How well maintained and how widely used is Fly.io? Built from what the vendor actually publishes (docs, changelog, tutorials, integrations, pricing), whether the site is live, and how much real users discuss it. How we calculate this
Last calculated: October 2026
How we score →Key Features
- Sprites: hardware-isolated Linux VMs with automatic checkpointing for AI agents
- Machines: hardware-isolated VMs booting in under 1 second
- Per-second billing for Machines, dropping to zero while idle
- Sprites billed hourly on active CPU, memory, and hot storage — no plans or per-Sprite fee
- Sprite Block Device: object-storage backed, up to 100 GB per Sprite, private beta
- Roll back to any checkpoint in seconds
- HTTPS URL per Sprite so agent-built apps go live where they were created
- Sprites Connectors for GitHub, Slack, OpenRouter, and any HTTP API
- Granular connector permissions by Sprite name, label, or single endpoint
- Auto key rotation across all connected Sprites
- Egress-locked, disposable VMs with a clean baseline per request for untrusted code
- Private networking with shared IPv4 and unlimited Anycast IPv6
- Zero-downtime deploys, 500ms typical deploy time, and autoscaling
- Managed Postgres with high availability, automated backups, and connection pooling
- 18+ global regions worldwide with a 99.9% uptime SLA
About Fly.io
Fly.io is a global compute platform for people shipping AI agents and the apps those agents build. The centerpiece is Sprites: hardware-isolated Linux VMs where each agent gets its own box that checkpoints itself while the agent works, so harnesses like Claude and Codex find the filesystem, running services, and installed dependencies exactly where they left off. A Sprite sleeps when the agent stops and wakes up remembering everything, which means you skip the external-database scaffolding that slows agent development. The platform pairs Sprites with Fly Machines. Machines are hardware-isolated VMs that boot in under a second, run across 18+ regions, and scale out to tens of thousands — the deployment target for whatever your agent produces. Every Sprite carries its own HTTPS URL, so an app your agent builds goes live where it was created with no migration step. Day-to-day features matter here. Sprites Connectors let you enable a connection to GitHub, Slack, OpenRouter, or any HTTP API once for the whole org, then reach it from as many Sprites as you like — with permissions granted by Sprite name, label, or a single endpoint, and auto key rotation when you cut one off. A Sprite Block Device, currently in private beta, is object-storage backed and grows as you write, up to 100 GB per Sprite, billed only for bytes stored. Managed Postgres adds high availability, automated backups, and connection pooling. The audience is developers, not casual users. You drive it through the flyctl CLI (with MCP support), and the same API carries from first sandbox to production. Compared with AWS Lambda or a managed serverless layer, Fly.io asks more of you — real infra concepts, no fully-managed click-and-deploy abstraction — but in return you get a genuine Linux computer per agent and a bill that drops to zero while idle.
Behind the Verdict
We'd reach for Fly.io the moment an agent needs to remember something past the current session. Sprites checkpoint automatically, so a harness like Claude or Codex resumes into the same filesystem, the same running services, the same dependencies. That single behavior removes a whole category of plumbing — no external state store, no object-store gymnastics, no re-hydrating a sandbox from scratch on every turn. If your agent build keeps stalling on "where did my files go," this is the fix. Pick it when you're running coding agents, hosting MCP servers with persistent disk and egress policy, executing untrusted code that needs a clean baseline per request, or giving a personal agent a home other than your laptop. The Sprites Connectors story is quietly the strongest part: configure a GitHub or Slack or OpenRouter connection once for the org, scope it by Sprite name, label, or a single endpoint, and rotate keys across every Sprite with one action. Nobody pastes a token onto a box. Pass when the workload is a static site or a simple API that a shared host or CDN serves for less. Pass, too, if your team wants a fully managed serverless abstraction where you never think about regions, rootfs, or VM presets — Fly.io expects you to understand infra, and the flyctl CLI is the front door. In practice, budgets behave differently than people expect. Sprites have no tiers and nothing charged per-Sprite: you pay metered by active use — CPU time at $0.0385 per CPU-hour, memory at $0.021875 per GB-hour, plus hot storage at $0.50 per GB-month while awake and cold storage at $0.02 per GB-month until you delete the data. Machines bill by the second and drop to zero when stopped, though stopped Machines still cost $0.15 per GB rootfs. Watch egress by region — it runs $0.02/GB in North
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Real-world workflow fit
Concrete scenarios for the personas Fly.io actually fits — and what changes day-one when you adopt it.
Spin up a Sprite with `sprite create`, let the agent work, and rely on automatic checkpointing so the filesystem and installed dependencies survive when the Sprite sleeps overnight.
Outcome: The agent picks up exactly where it left off the next morning, with no external database or state-management layer to build.
Run each MCP server in its own Sprite with a Sprites Connector granting endpoint-scoped access to GitHub or Slack, so tokens never land on the Sprite.
Outcome: Tool calls bill per usage, credentials rotate centrally, and revoking one Sprite doesn't disrupt the rest.
Execute user-submitted code in a hardware-isolated Sprite with egress policy locked down and a clean baseline per request.
Outcome: No two users ever share state, and a rogue request can't reach the network or other VMs.
Use Cases
- Run AI coding agents like Claude or Codex in isolated VMs where checkpoints preserve state across sleeps.
- Host every MCP server in its own Sprite with persistent disk and egress policy, paying only for tool calls used.
- Execute untrusted or AI-generated code in disposable, egress-locked VMs with a clean baseline per request.
- Run personal agents with inbox or calendar access on a Sprite that sleeps and wakes remembering everything.
- Deploy globally distributed Rails or Phoenix apps with sub-second boots across 18+ regions.
- Ship an app your agent just built via its own HTTPS URL, staying exactly where it was created.
- Host managed Postgres clusters from $38/mo (Basic) up to $1,922/mo (Performance) with HA and backups.
- Run ephemeral worker VMs that autoscale and auto-stop, billed per second of active compute.
Models Under the Hood
as of 2026-10-16
Limitations
- Compute is strictly usage-based — Machines bill by the second while running, and Sprites meter per hour of active use with no plans, tiers, or per-Sprite fee, so costs scale directly with usage.
- Machines storage and egress are priced separately from compute, and VM presets cost more RAM at $6.00 per GB per month, with preset hourly rates ranging from $0.0030 (shared-cpu-1x) to $0.7334 (performance-16x).
- Egress is region-dependent ($0.02/GB in North America and Europe up to $0.12/GB in Africa and India).
- The platform is developer-focused, provisioning and managing through CLI and infrastructure concepts rather than a click-and-deploy GUI.
as of 2026-09-29
Verification history
We have re-verified Fly.io 20 times since . Each pass re-reads the vendor's own pages and re-checks every listed field against that evidence; passes where nothing had changed are marked as such.
- — re-checked, vendor evidence unchanged
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
Showing the 6 most recent of 20 verification passes.
Free to cite with attribution — this page re-verifies continuously.
12-month cost
Project the real annual outlay, including the implied monthly cost when only an annual tier is published.
Vendor list price only. Add-on usage, seat overages, and contract minimums are surfaced under Hidden costs & gotchas.
Plans compared
For each published Fly.io tier: who it actually fits, and what it adds vs. the previous tier. Cross-reference the cost calculator above for projected annual outlay.
Free
$0/mo
Ideal for
Solo developers and hobbyists evaluating Sprites or Machines before committing to a paid workload, and anyone running occasional lightweight agents.
What this tier adds
Starting tier — includes a free compute and storage allotment, access to Sprites and Machines, and community support.
Machines (shared-cpu-1x · 256MB)
$2.19/mo ($0.0030/hr)
Sprites (usage-based)
$0.0385 / CPU-hour
Managed Postgres — Basic
$38/mo
Managed Postgres — Starter
$72/mo
Managed Postgres — Launch
$282/mo
Standard Support
$29/mo
Ideal for
Single developers and small teams on personal projects or early-stage startups who want a guaranteed response from Fly's engineering team.
What this tier adds
Adds paid support on top of compute — 36-hour first response time and technical architecture support.
Premium Support
$199/mo
Ideal for
Growing businesses scaling production applications who need faster response and a direct channel to Fly.io engineers.
What this tier adds
Upgrades support to 24-hour first response, 1-hour urgent response, dedicated Slack channel, and quarterly solutions architecture sessions.
Where the pricing makes sense
The company stage and team size where Fly.io's pricing actually pencils out — and where peers do it cheaper.
Sprites and Machines are usage-metered, so the effective bill depends entirely on how much your workload actually runs — a solo developer running light agent workloads can start free and stay near $0, while a team running dozens of always-awake Sprites or the Performance Postgres tier at $1,922/mo is in enterprise cloud territory. Against AWS Lambda (function-level billing, more abstraction) Fly.io gives you full VMs; against a reserved EC2 instance ($30-300/mo range for comparable specs)
Setup time & first value
How long it actually takes to get something useful out of Fly.io — broken out by persona, not the marketing-page minute.
Solo developer running a first Sprite: install flyctl (`brew install flyctl`) and run `sprite create` — first value within minutes. Team deploying a full app with Machines and Managed Postgres: plan a few hours for region choice, Postgres provisioning, and networking configuration. Agent-hosting a fleet of MCP servers with Connectors: budget a day for connector setup, permission scoping, and
Switching to or from Fly.io
How to bring data in from common predecessors and how to get it back out — written for the switcher, not the buyer.
- →From raw AWS Lambda / serverless: replace function-level abstraction with Machines or Sprites when you need persistent filesystem, checkpoints, or a full Linux VM.
- →From a container sandbox provider: move agent code to Sprites to get automatic checkpointing and hardware isolation instead of ephemeral containers.
- →From self-managed Postgres: migrate to Managed Postgres (starting at $38/mo Basic) for HA, automated backups, and connection pooling.
- →From a single-region VM host: redeploy onto Machines to pick up 18+ regions and sub-second boot times without rearchitecting.
- ↗To AWS Lambda or another fully managed serverless platform: rewrite compute as stateless functions if you decide the CLI and infra concepts are too much.
- ↗To a container sandbox provider (e.g., E2B-style offerings): move agent code if you don't need checkpoint/restore or hardware isolation.
- ↗To a managed Postgres provider: export your database if you outgrow the Managed Postgres tiers.
- ↗To a traditional VPS host: redeploy long-running VMs if your workload runs 24/7 and reserved instances are cheaper.
Integrations
Resources & Guides
- Documentationfly.io
Docs · Fly.io
Full product docs from fly.io
- Quickstartfly.io
Getting Started · Fly.io
Get up and running fast from fly.io
- Documentationfly.io
Machines · Fly.io
Full product docs from fly.io
- Documentationfly.io
Sprites · Fly.io
Full product docs from fly.io
- Documentationfly.io
Postgres · Fly.io
Full product docs from fly.io
- Documentationfly.io
Networking · Fly.io
Full product docs from fly.io
- Documentationfly.io
Monitoring · Fly.io
Full product docs from fly.io
- Documentationfly.io
Security · Fly.io
Full product docs from fly.io
- API Referencefly.io
Reference · Fly.io
Methods, params, types from fly.io
- Documentationfly.io
Languages And Frameworks · Fly.io
Full product docs from fly.io
Tutorials & Learning
What the Fly? そもそもFly.ioって何ですか?
Fly․io
60秒でFly.io
Fly․io
Fly.io にアプリをデプロイする | SvelteKit のサンプル アプリを Dockerize して起動します。
Consulting Ninja
YouTube returned 6 videos for “Fly.io”, and we withheld 1: 1 could not be judged, because “Fly.io” is a single word that other videos use for other things. Showing the 5 we can prove are about Fly.io.
Official links
Tools that pair well with Fly.io
Common stack mates teams adopt alongside Fly.io, with the specific reason each pairing earns its keep.
Fimo
Fimo runs autonomous website agents on your own Git repo, keeping your site self-updating after launch.
E2B
E2B spins up isolated Linux sandboxes per second so AI agents can run code, process data, and use tools without touching your host.
Hostinger
Agentic web hosting where AI Builder generates your site and Hostinger Agent manages it — included on every plan.
Featured Head-to-Head Comparisons
Fly Io vs Spider Cloud
These are not competitors — pick by the problem, not against each other. If your bottleneck is getting live, rendered web pages into an agent or RAG pipeline (CAPTCHAs, bot walls, infinite scroll, whole-site crawls), Spider Cloud is the obvious buy. If your bottleneck is giving an agent a persistent, hardware-isolated computer with checkpointing and near-zero idle cost, Fly.io is the obvious buy. Many teams will end up paying for both: Fly.io runs the agent, Spider Cloud feeds it the web.
Fly Io vs Temporal Ai
These are not competitors — they're layers in the same stack. Temporal is for orchestrating long-running, stateful business processes (order fulfillment, Saga compensations, durable AI agent flows), while Fly.io sells raw compute: hardware-isolated Linux VMs that checkpoint themselves so sandboxed agents can restart where they left off. Most teams that need one don't need the other, though a sophisticated AI agent platform could conceivably use Fly.io Sprites as execution environments while Temporal coordinates the overall workflow. If you're building a coding agent or MCP server that needs a real computer, pick Fly.io. If you need guaranteed completion of multi-step workflows with retries and rollback, pick Temporal.
Fly Io vs Audioeye
These are not alternatives — they solve unrelated problems for unrelated buyers. Pick AudioEye if your problem is ADA/WCAG exposure: it pairs automated scanning and AI remediation with human audits, a visitor-facing overlay, VPAT/ACR docs, and legal support, aimed squarely at enterprises in litigious verticals like e-commerce. Pick Fly.io if your problem is giving AI agents a real computer: its Sprites are hardware-isolated Linux VMs that auto-checkpoint, boot in under a second, roll back in seconds, and bill per second down to zero when idle — currently in the middle of a strategic pivot toward agent sandboxes. Nobody is weighing an accessibility overlay against an agent sandbox. Budget accordingly and don't cross-shop them.
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