Application hosting / PaaS: read the guide

Fly.io

HostedPaaS

Hardware-isolated VMs that boot in under a second, run close to your users, and scale out to tens of thousands.

Homepage Docs Pricing

Scanned 14 Oct 2026 · Schema v5 · features v21

From: $29/mo
Usage-based Pay As You Go; no monthly platform fee; per-second running compute with region-dependent rates; optional 40% reservation blocks and paid support.
Free tier: No
Card required.
Isolation: Firecracker microVM
shares only the hypervisor
Regions: 17
Ashburn, US · Chicago, US · Secaucus, US · Los Angeles, US · San Jose, US · Dallas, US +11
Capabilities: 34 / 61
0 partial · 26 fail · 0 not assessed
Agent readiness: 11/11 · 10/11
read · drive, pre-login surface

Advertised for

Web apps · Background workers · Globally distributed apps · Containerized services · Stateful applications

Built for

Developers, then technical

· https://fly.io/agents.md — Dockerfile, fly launch, fly deploy and Machines API workflows.
· https://fly.io/pricing.md — compute CPU/RAM usage pricing.

01 Pricing Usage-based Pay As You Go; no monthly platform fee; per-second running compute with region-dependent rates; optional 40% reservation blocks and paid support.

Tier	EntryPay As You Go	Shared Machine reservation	Performance Machine reservation	TopStandard Support (optional)
Price	No monthly platform fee; smallest always-on Machine $2.19 per 30 days	$36/year for $5/month shared compute credit in one region	$144/year for $20/month performance compute credit in one region	$29/month; Premium $199/month; Enterprise from $2500/month
Includes	No included compute; shared IPv4, IPv6, inbound transfer, 10 single-host certificates, first 10GB snapshot storage free.	—	—	—
Storage overage	$0.15/GB	—	—	—

Machine preset and region per running second; 30-day monthly illustrations; storage GB-month and network GB.·Card required: Yes·docs.fly.io

Overages: Regional compute; extra RAM $6/GB-month; volume $0.15/GB-month; stopped rootfs $0.15/GB-month; snapshots $0.08/GB-month (10GB free); internet egress $0.02/0.04/0.12 per GB; cross-region private $0.006/0.015/0.050 per GB; dedicated IPv4 $2/mo; static egress $0.005/hour.

02 Website design Desktop public website · assessed 14 Oct 2026

Complete assessment.

Playful hand-drawn purple characters and pastel color fields pair with serif headlines; pricing and docs retain the illustrative brand within a structured three-column reference layout.

Playful

Landing page: captured
Pricing: captured
Docs: captured

03 Runtime Each fact carries its source; dots show confidence. Open a row for the evidence.

Isolation & lifecycle

Isolation primitive

Firecracker microVMshares only the hypervisor

Persistence

Fly Volumes provide local persistent NVMe storage on the same physical server as a Machine. Root filesystem is ephemeral across Machine updates/restarts; use volumes for durable app data. Stopped Machine rootfs remains billable.

Snapshots / forks

Yes

Resources & limits

Storage

Local NVMe Fly Volumes $0.15/provisioned GB-month; incremental snapshots $0.08/stored GB-month, first 10GB free; third-party Tigris object storage billed separately at provider list prices plus network.

Limits & quotas

Organization automated scaling limits apply. Trial: 2 total VM-hours or 7 days; max 10 Machines, 20GB volumes, 2 vCPUs and 4GB RAM/Machine; trial Machines auto-stop after 5 minutes.

GPU

Not currently offered in the resource pricing; deprecated GPU product has passed its stated August 1 sunset.

Access

Deploy interface

cliapicontainer-imagedockerfilemcp

SDK languages

Network & secrets

Egress controls

Static egress IPs available; no general outbound deny-all/allowlist firewall established for Machines.

Secrets

Encrypted app vault; secrets injected as environment variables at boot on every app Machine; can also mount base64 secrets as files. Deploy access can exfiltrate secrets.

Bring your own cloud

Placement & use

Jurisdiction

amsarncdgdfwewrfragruiadjnblaxlhrnrtordsinsjcsydyyz

Advertised workloads

Web appsBackground workersGlobally distributed appsContainerized servicesStateful applications

04 Capabilities 34 pass · 0 partial · 26 fail · 61 of 61 assessed

Supported — Documented on the public surface and verified.
Partially supported — Exists with caveats: gated, thin, or enterprise-only.
Not supported — Checked and not offered.
Not assessed — Scanned before this capability was tracked. Not a lack.

Compute & storage 7/11

Persistent diskStorage that survives restart/stop (not ephemeral-only).

Supported

Object storageManaged S3-compatible / blob object store the platform PROVIDES to a user's workloads (buckets, presigned URLs). DISTINCT from persistent-disk (block/volume attached to an instance) and from a self-host dependency (source.self_host.deps[]=["object-storage"] is an infra dep to RUN an OSS tool — the opposite direction). SCOPE varies and matters: native first-class (Railway Buckets, Cloudflare R2) vs a sibling SKU / extension (Fly Tigris, Bunny Storage, DigitalOcean Spaces) — record which in the evidence quote / note. Admitted v15.

Supported

Snapshots / forkingSnapshot or copy-on-write fork of a running instance (filesystem-only counts). Whether the snapshot also restores memory + running processes is recorded separately by memory-snapshot (v19).

Supported

Live-state (memory) snapshotsA snapshot / checkpoint / pause captures a running instance's MEMORY and PROCESS state and restores it, so running processes continue where they left off instead of a freshly booted instance with the same files. Counts whether user-triggered (snapshot, checkpoint, pause-to-storage) or used to restore pre-initialised state (memory snapshots for fast cold starts). Distinct from snapshots-forks (any snapshot or fork, including filesystem-only; a product passing that key may still fail this one) and from scale-to-zero (an idle-cost property; suspension may or may not keep memory). Actor multiplexing (see scale-to-zero) records its live-state half here — only when the suspended actor's MEMORY/process state is what comes back, not a freshly booted worker with the actor's files.

Supported

Scale to zeroIdle instances suspend at no / negligible cost. ACTOR MULTIPLEXING (many suspended stateful actors sharing a small pool of pre-warmed workers, woken on request — Agent Substrate, AX, kagent; Rivet's hibernating actors) has NO key of its own (proposal REJECTED v20) — score the idle-cost half HERE and the live-state half under memory-snapshot; the oversubscription ratio / density is a performance characteristic the registry does not key.

Supported

GPU computeGPU-backed instances available.

Not supported

Multi-regionCompute placeable in more than one geographic region.

Supported

Sandbox templates / custom imagesBuild reusable sandbox/VM images from an OCI image or Dockerfile (a base you fork instances from).

Supported

Cloud-init / ignition configCustomise a VM / microVM / instance at boot via cloud-init (or ignition) user-data — the same boot-metadata interface as AWS/Azure/GCP. Inject packages, users, SSH keys, files, and run-commands declaratively at launch. Distinct from sandbox-templates (a PREBUILT image you fork instances from) — this is PER-LAUNCH declarative customisation, not a baked image.

Not supported

Desktop / computer-use sandboxA virtual desktop (GUI) for LLM computer-use — browser + desktop automation, often via noVNC/VNC.

Not supported

Selectable isolation runtimeThe user chooses the isolation runtime per workload / environment / sandbox from more than one option (e.g. microVM vs gVisor vs plain container, native namespaces vs gVisor, gVisor vs VM). Records the CHOICE; the isolation_primitive facet still records the best-evidenced primary. A platform that switches runtime automatically without a user choice (e.g. gVisor forced for GPU) does not pass on that alone.

Not supported

Networking & delivery 6/9

Automatic HTTPSTLS endpoints provisioned automatically per workload.

Supported

Built-in reverse proxyPlatform routes external traffic to workload services.

Supported

Custom domainsBring-your-own domain via CNAME/DNS.

Supported

Public preview URLsShareable per-deploy / per-branch URLs.

Supported

Direct public IPv6Per-instance stable public IPv6 for raw TCP/UDP (beyond a managed HTTPS proxy) — e.g. mosh / raw sockets.

Not supported

Egress controlsConfigurable OUTBOUND network policy — egress firewall / allowlist / egress proxy on traffic LEAVING a workload. Scoped to OUTBOUND only (v15): private-network REACHABILITY between a user's own services is private-networking, not this. Static-egress-IP belongs here (an outbound concept).

Supported

Private networkingA platform-internal private network between a user's OWN services — service-to-service connectivity, VPC, service mesh, and/or service discovery, not exposed to the public internet. DISTINCT from egress-controls (OUTBOUND firewall/allowlist), reverse-proxy (PUBLIC inbound ingress), and direct-ipv6 (per-instance PUBLIC addressing). Admitted v15.

Supported

Email send / receiveSend and/or receive email from the workload.

Not supported

Edge KV storeA globally-replicated key-value store read from WITHIN an edge runtime at the PoP (low-latency, eventually-consistent) — Cloudflare Workers KV, Deno KV, Fastly KV Store, Akamai EdgeKV, Vercel Edge Config. Distinct from first-party-db (a managed DATABASE service you provision and connect to) and from http-query-api (HTTP access to an external store) — edge-kv is colocated with the edge compute and read at the edge.

Not supported

Developer access 7/10

Public APIDocumented programmatic API.

Supported

OpenAPI specMachine-readable OpenAPI / Swagger spec published.

Supported

CLIOfficial command-line tool.

Supported

SDKOfficial client library/libraries.

Supported

SSH accessDirect SSH into workloads.

Supported

Filesystem APIRemote file operations over the API (list/read/write/watch/copy/upload) without SSH.

Not supported

Git deployDeploy from a Git repo / push-to-deploy.

Supported

Private container registryHosted private image registry.

Supported

E2B-compatible APIDrop-in compatibility with the E2B sandbox API/SDKs — existing E2B client code runs against this product by changing the endpoint/domain + key, with no business-code changes. E2B itself passes as the reference implementation. Distinct from public-api / sdk (the product has its own API — this key says it also speaks another vendor's) and from self-host-oss (a self-hosted E2B-compatible server is scored on both).

Not supported

HTTP data APIQuery / read / write the stored DATA over plain HTTP/REST (or GraphQL) WITHOUT the native protocol driver (Postgres wire / Redis RESP) — agent- and edge-friendly data access via fetch(). The DATA plane; distinct from public-api (a control-plane / management API). Auto-generated-from-schema REST/GraphQL (PostgREST, pg_graphql) is a flavour of this.

Not supported

AI & agents 4/11

Built-in coding agentShips a first-party AI coding agent in the product.

Not supported

Agent skillsInstallable / declarable agent skills or tools.

Supported

AI app builderPrompt-to-app / vibe-coding generation surface.

Not supported

MCP serverExposes a Model Context Protocol server for agents.

Supported

MCP clientActs as an MCP client / consumes MCP tools.

Supported

MCP-server hostingRun/host MCP servers as a workload on the platform (distinct from exposing a first-party MCP control server — that is mcp-server).

Supported

LLM gatewayRoutes LLM API calls through the platform (multi-provider).

Not supported

BYOK for LLMsBring-your-own LLM provider keys.

Not applicable

Model inference API (first-party)A FIRST-PARTY hosted LLM/model inference API — the provider serves its OWN catalogue of (usually open-weight) models behind a (typically OpenAI-compatible) endpoint, billed per token. Distinct from llm-gateway (a multi-PROVIDER proxy/router for YOUR calls to external providers like OpenAI/Anthropic) and from byok-llm (bring your own provider keys) — here the platform IS the inference provider, serving its own models.

Not supported

Autonomous QA agentA first-party AUTONOMOUS AI agent that QA-TESTS a running app / implementation — exercising it like a real user (clicking through flows, checking behaviour) and reporting bugs/defects (often back to a coding agent, or before a human review). Distinct from built-in-agent (a code-AUTHORING agent — this one VERIFIES the result, it does not write the feature; a product can ship both), from ai-guided-code-review (organises a diff for a HUMAN to review — not an autonomous tester), and from observability (runtime metrics/logs, not active testing).

Not supported

Credential-injection proxyThe platform holds real secrets OUTSIDE the workload and injects them on the wire (an egress / broker proxy swaps a placeholder or phantom token for the real credential on matching outbound requests), so code running in the sandbox — e.g. an untrusted agent — never sees or can exfiltrate the real key. Distinct from secrets-management (storage + injection INTO the workload as env vars/files — the workload holds the secret) and from egress-controls (outbound allow/deny POLICY; a product can have an allowlist without injecting credentials, and vice versa).

Not supported

Preinstalled coding agentThe platform installs and launches a THIRD-PARTY coding agent (a harnesses.yml entry — Claude Code, Codex, OpenCode, Pi ...) inside a workspace/sandbox it provisions, with the agent's auth wired in (your own account or API key), so you start an agent session rather than an empty box. Distinct from built-in-agent (a FIRST-PARTY agent the vendor ships) and from harnesses[] (which records that a harness CAN target the product, not that the product runs it for you).

Not supported

Data 2/4

First-party databasePlatform-provided managed database.

Supported

Database branchingCopy-on-write branch of a DATABASE (schema + data) as a dev-lifecycle primitive — branch your data like code, usually instant via a metadata operation. Distinct from snapshots-forks (forks a running compute INSTANCE / VM state) and from preview-environments (a full per-PR environment that may USE a DB branch). For a data product a CoW branch maps HERE, not to snapshots-forks.

Not supported

Vector searchFirst-class storage, indexing, and similarity search of vector embeddings — a native vector type/index or a managed vector DB. The data-layer primitive for RAG / semantic retrieval.

Supported

Ephemeral instant DB (no-signup)Provision a working, usable instance via a single command / HTTP call with NO account, signup, or card — typically time-boxed (expires unless claimed). A zero-onboarding path an agent can hit directly.

Not supported

Platform & operations 3/6

Scheduled tasksCron / scheduled job primitive.

Supported

Durable workflowsDurable execution / long-running workflow primitive.

Not supported

Preview environmentsA full EPHEMERAL environment spun up per PR / branch — compute + addons + (often) a DB branch — torn down on merge. More than preview-urls (which is just a shareable URL for one deploy).

Supported

Built-in observabilityFirst-party metrics / logs / tracing / APM / profiling included in the platform (no third-party stack required to see what a workload is doing).

Supported

Managed CI/CD runnersPlatform-hosted, drop-in CI/CD runner VMs (GitHub Actions / GitLab), typically faster and cheaper than the CI vendor's own hosted runners, billed per runner-minute; isolated + ephemeral per job. Distinct from git-deploy (push-to-deploy of an APP) and scheduled-tasks (cron) — this is managed CI COMPUTE you point your existing pipelines at.

Not supported

Project template marketplaceA marketplace / gallery of prebuilt PROJECT STARTER templates (apps or websites) a user clones or launches a new project from and then customises — the "start from a template" surface of a builder / PaaS. Distinct from sandbox-templates (a COMPUTE base IMAGE you fork runtime INSTANCES from — Dockerfile / OCI), from app-builder (the prompt-to-app GENERATION surface — a product can have both), and from one-click OSS-app catalogues / helm-addon-marketplace (deploy a FINISHED app as-is, not a starter you build on).

Not supported

Organisation & security 5/9

Built-in authPlatform-provided authentication / IAM for workloads.

Not supported

SSO / SAMLEnterprise single sign-on.

Supported

Secrets managementFirst-class secrets storage / injection.

Supported

TeamsMulti-user team accounts.

Supported

SharingShare a running workload/resource via link (optionally gated).

Supported

BYOCRuns inside the customer's own cloud account.

Not supported

Deploy into customers' VPCsA SaaS vendor uses the platform to deploy and operate ITS software inside ITS CUSTOMERS' cloud accounts / VPCs (nested or "customer BYOC"), managed from the vendor's control plane. Distinct from byoc (your own workloads in your own cloud account).

Not supported

Workload identityThe platform gives each workload its own verifiable identity (OIDC token, SPIFFE SVID, cloud IAM federation) that it exchanges for short-lived credentials, so no long-lived static secret is stored or injected. Distinct from secrets-management (stores / injects static secrets) and credential-injection-proxy (swaps real secrets in on the wire).

Supported

Self-host / OSS coreOpen-source core that can be self-hosted.

Not supported

Proposed, not verified

Capabilities the scan saw but the registry does not track yet. A key is admitted only once two distinct products exhibit it. These are not scored.

Managed Kubernetes (closed beta)managed-kubernetes
“Fly Kubernetes is in closed beta and not recommended for critical production usage.” fly.io

05 Agent readiness Pre-login surface · counts, not a grade

Can an agent read it?

parse-ability · docs, metadata, machine-readable surfaces

11/11

11 full · 0 partial · 100% of applicable checks

llms.txt
Supported
“https://fly.io/llms.txt — substantive product, pricing, docs, API, SDK and tooling links.”
llms-full.txt
Supported
“https://fly.io/docs/llms-full.txt — HTTP 200, 2,858,797 bytes of comprehensive documentation; capped pointer retained.”
robots.txt AI policy
Supported
“https://fly.io/robots.txt — User-agent: *; Content-Signal: search=yes, ai-input=yes, ai-train=yes; Allow: / (dashboard excluded).”
JSON-LD
Supported
“https://fly.io/ — seven JSON-LD blocks, including SoftwareApplication and Service as well as Organization/WebSite.”
Sitemap
Supported
“https://fly.io/sitemap.xml is a sitemap index; https://fly.io/sitemap-landing.xml contains a substantive 83,343-byte URL set.”
Meta tags
Supported
“https://fly.io/ — descriptive title Fly.io | Computers for agents, description and Open Graph metadata.”
Markdown negotiation
Supported
“https://fly.io/ requested with Accept: text/markdown returned clean Markdown with YAML frontmatter; explicit index.md and docs .md variants also fetched.”
Content efficiency
Supported
“https://fly.io/ — HTMLParser excludes script/style text: 6360 readable bytes / 94137 HTML bytes = 6.76%, above 5%.”
Docs discoverable
Supported
“https://fly.io/ — Platform Docs and Sprites Docs in server-rendered navigation.”
Machine-readable pricing
Supported
“https://fly.io/pricing.md — parseable Machines CPU/RAM prices and managed Postgres plans.”
No anti-bot wall
Supported
“All fetched public homepage/docs/pricing/spec/well-known sources were accessible without a challenge; expected nonexistent paths returned 404.”

Can an agent drive it?

act-ability · APIs, SDKs, MCP, credentials, webhooks

10/11

8 full · 2 partial · 91% of applicable checks

Public API
Supported
“https://fly.io/docs/machines/api/index.md — documented Machines REST API.”
OpenAPI spec
Supported
“https://docs.fly.io/api/machines/openapi.json — parsed JSON OpenAPI 3.1.0 with paths/components; auth/skill links also lead to https://docs.machines.dev/openapi.json (fetched).”
MCP server
Supported
“https://docs.fly.io/flyctl/cmd/fly_mcp_server.md — documented fly mcp server command; not dependent on absent /.well-known/mcp.”
SDK packages
Partially supported
“https://fly.io/llms.txt — official fly-go for Machines/GraphQL; multi-language Sprites SDKs excluded from hosted PaaS SKU.”
Auth documented
Supported
“https://fly.io/auth.md and https://docs.fly.io/security/tokens.md — Bearer authentication, scoped tokens, expiry, attenuation and revocation.”
Self-serve credentials
Supported
“https://fly.io/auth.md — fly tokens create deploy/org/readonly/ssh/machine-exec with --json and --from-existing documents programmatic scoped token issuance after human-authorized bootstrap. Anonymous agent registration is explicitly unsupported.”
Webhooks
Not supported
“https://fly.io/docs/llms.txt — no platform outbound webhooks with signing documentation found; GitHub workflow hooks are not platform outbound webhooks.”
CLI tool
Supported
“https://fly.io/docs/flyctl/index.md — official flyctl CLI.”
Error model
Supported
“https://docs.fly.io/api/machines/openapi.json — ErrorResponse object with error string, status and deprecated details; https://fly.io/auth.md gives literal JSON authentication error.”
Rate limits documented
Partially supported
“https://docs.fly.io/machines/api/working-with-machines-api.md — 1 request/sec/action/Machine, burst 3; Get Machine 5/sec burst 10; app deletions 100/min; rate-limit response headers not documented here.”
Agent config files
Supported
“https://fly.io/agents.md plus https://fly.io/.well-known/ard.json and https://fly.io/agent-skills/fly-machines-api/SKILL.md — multiple discoverable agent configuration/skill surfaces.”

06 Coding harnesses Which agents and IDEs are documented to run here

Advertised integrations 5

OpenClaw Peter Steinberger
Supported
“Deploy OpenClaw on Fly.io”
Source docs.fly.io
Hermes Agent Nous Research
Supported
“Run Hermes Agent on Fly.io”
Source docs.fly.io
Cursor Anysphere
Supported
“--cursor Add flyctl MCP server to the Cursor client configuration”
Source docs.fly.io
Zed Agent Zed
Supported
“--zed Add flyctl MCP server to the Zed client configuration”
Source docs.fly.io
Windsurf Codeium
Supported
“--windsurf Add MCP server to the Windsurf client configuration”
Source docs.fly.io

Plausible compatibility 14

Derived, not stored: the product passes SSH access, so any CLI coding agent is installable inside it. This is plausible compatibility, not a supported integration.

Aider
Amp
Antigravity
Claude Code
Codex CLI
Devin
Droid
Gemini CLI
Goose
Kilo Code
Kiro CLI
OpenCode
Pi
Qwen Code

07 Compliance & regions Standards held, with ordinal rigor; never a score

Certifications held 3

SOC 2 Type II
certifiedhosted
“SOC2 Type2 Report — independently audited, certified.”
Source fly.io
HIPAA
self-attestedhosted
“Business Associate Agreement — pre-signed by Fly.io and active when you sign it.”
Source fly.io
GDPR
self-attestedhosted
“Data Processing Agreement — Users who need to comply with GDPR; pre-signed by Fly.io.”
Source fly.io

Regions 17

Ashburn, USiad
Chicago, USord
Secaucus, USewr
Los Angeles, USlax
San Jose, USsjc
Dallas, USdfw
Toronto, CAyyz
London, UKlhr
Amsterdam, NLams
Paris, FRcdg
Frankfurt, DEfra
Stockholm, SEarn
Tokyo, JPnrt
Singaporesin
Sydney, AUsyd
São Paulo, BRgru
Johannesburg, ZAjnb

17 entries in current authoritative regions table; Mumbai bom no longer listed. Homepage advertises 18+, a vendor surface discrepancy; use explicit table for placement.

Legal

Privacy notice Terms of service

08 Company & presence Facts only, not scored

Company

Headquarters: Not disclosed
Founded: 2017
Team size: Not disclosed
Hiring: Hiring: Account Manager (US), Fullstack Engineer (Remote), Infrastructure Operations Engineer (Remote), Networking Engineer (Remote)

Funding

2026-07-24Series D · $25 millionfly.io

Notable people

Scott Johnston — CEO
Kurt Mackey — founder, board member and advisor
Ben Johnson — VP of Product
Michael Stahnke — VP of Engineering
Thomas Ptacek — Developer

Activity

Last release: flyctl v0.4.118 — 2026-10-14T19:13:32Z (CLI release; not a hosted-platform version) api.github.com
Last blog post: 2026-09-03 — Your Agent Speaks MCP. Give It a Computer. (site-wide latest listed blog; Sprites topic, not Machines functionality) fly.io

Presence 6

Links found on the public surface scanned; not an exhaustive search.

09 Sources & method How this entry was produced

Public surface only

Everything here was read from fly.io's unauthenticated pages, docs, pricing and repository on 14 Oct 2026. Nothing behind a login was used.

Statuses, not scores

Capabilities are pass, partial or fail against a written rubric (features v21). “Not assessed” means the scan predates the key.

Confidence is separate

Each fact carries its own confidence. Low-confidence facts are shown, never hidden, so you can weigh them.

Schema: scan v5
Features registry: v21
Keys tracked today: 61
Assessed on this entry: 61

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