use-cases / a-ci-cache-thats-just-two-curl-commands / hero

PIPE · CI · COST OPTIMIZE

A CI cache that's just two curl commands

The first job in your pipeline tars node_modules and pipes it to a Hoody URL. Twenty downstream jobs curl that same URL and untar. With ?n=20 the producer waits for all twenty workers to connect, then streams once — fanned out to all of them. No S3 bucket, no cache action, no egress bill.

Read the pipe docs

ci · job-build

$tarcnode_modules|zstd|curl -T -hoody.com/pipe/cache

WAITING FOR 20 RECEIVERS · UPLOAD HELD

pipe/cache?n=20

800 MB · STREAMED ONCE

ci · test workers

20 / 20 CONNECTED

job-01

curl … | zstd -d | tar x

job-02

curl … | zstd -d | tar x

job-03

curl … | zstd -d | tar x

job-04

curl … | zstd -d | tar x

job-05

curl … | zstd -d | tar x

job-06

curl … | zstd -d | tar x

job-07

curl … | zstd -d | tar x

job-08

curl … | zstd -d | tar x

job-09

curl … | zstd -d | tar x

job-10

curl … | zstd -d | tar x

job-11

curl … | zstd -d | tar x

job-12

curl … | zstd -d | tar x

job-13

curl … | zstd -d | tar x

job-14

curl … | zstd -d | tar x

job-15

curl … | zstd -d | tar x

job-16

curl … | zstd -d | tar x

job-17

curl … | zstd -d | tar x

job-18

curl … | zstd -d | tar x

job-19

curl … | zstd -d | tar x

job-20

curl … | zstd -d | tar x

use-cases / a-ci-cache-thats-just-two-curl-commands / flow

The whole mechanic in two shell lines

There is no client library, no daemon, no SDK. The producer streams its tarball into PUT /pipe/cache?n=20. Each worker streams it back out of GET /pipe/cache?n=20. The pipe holds the bytes only while they're in flight — never on disk.

PUT · PRODUCERRUN ONCE PER BUILD

Produce the cache

$tar c node_modules|zstd|curl -T -

https://hoody.com/pipe/cache?n=20

# blocks until 20 receivers connect, then streams once

tar packs node_modules; zstd compresses on the fly; curl PUTs the bytes straight into the pipe path. No tempfile, no upload-artifact step, no bucket credentials.

GET · CONSUMERRUN ON EVERY WORKER

Consume the cache

$curlhttps://hoody.com/pipe/cache?n=20

| zstd -d | tar x

# fan-out: every worker gets an identical copy

Each test worker GETs the same URL, decompresses, and untars into its working directory. Slow workers apply backpressure to the producer but don't block faster ones.

THE WHOLE COORDINATION SURFACE?n=20

One query parameter. Producer and consumer agree on the same n. The pipe holds the upload until exactly that many receivers are connected, then opens the floodgate.

use-cases / a-ci-cache-thats-just-two-curl-commands / relief

What you stop paying for

CI caching used to be a tax: storage you'll overwrite tomorrow, egress every time a worker pulls, engineering time on the cache action's quirks. The pipe deletes all three line items at once.

No bucket. No egress bill.

There is no S3 bucket because there is no storage. The pipe forgets the bytes the second the transfer ends, so there is nothing to charge per-GB-month or per-GB-out for. The cache stops being a line item.

No cache action quirks

No yaml-encoded keys, no save-cache / restore-cache split, no debugging why a cache hit didn't happen on the right runner. Just curl. The same two lines run on GitHub Actions, BuildKite, Jenkins, your laptop, or a cron container.

No key collisions across branches

Branches just use different paths. /pipe/cache/main, /pipe/cache/feat-x, /pipe/cache/PR-742. Nothing to invalidate. Nothing to evict. When the branch dies, its path stops being asked for and that is the entire lifecycle.

use-cases / a-ci-cache-thats-just-two-curl-commands / compare

The cost shape, before and after

On a real workload — node_modules around 800 MB, twenty parallel test workers, a hundred CI runs a day — most of the bill is egress, not storage.

S3 + GH ACTIONS CACHE

20× egress

Each of the twenty workers pulls the cache out of S3. Twenty downloads of an 800 MB tarball is 16 GB of egress per CI run. The bucket itself is the easy part — the egress is what compounds.

HOODY PIPE · ?n=20

1× transfer

The producer streams the 800 MB once. The pipe fans the bytes out to all twenty receivers in flight. One transfer through the wire, no per-receiver multiplier, no storage bill.

Numbers are illustrative for a typical Node monorepo cache. Actual savings depend on tarball size, worker fan-out, and the egress price your provider charges out of the cache region. The shape — linear vs. constant in worker count — is invariant.

use-cases / a-ci-cache-thats-just-two-curl-commands / punchline

The cache layer is HTTP. It always was. We just hadn't noticed.

Caches were never about storage. They were about getting the same bytes to N workers without rebuilding. HTTP already does that — once you let one URL fan out to a known number of receivers. The bucket was a workaround for the fan-out we didn't have.

BYTES

Stream once, fan out

One PUT, n GETs, identical bytes. Backpressure is per-receiver so the slow worker doesn't slow the fast ones.

PUT /pipe/cache?n=20

TIME

Live only in flight

The pipe holds the bytes for the transfer and forgets them when it ends. There is nothing to evict, nothing to lifecycle, nothing to back up.

TTL ≤ 5 min · then evicted

PATH

Branches are paths

Each branch picks its own path. No shared keyspace, no collisions. The path is the cache key and the URL at once.

/pipe/cache/[branch]

Read the pipe API

use-cases / a-ci-cache-thats-just-two-curl-commands / replaces

What this replaces

Most CI caches solve the same problem: get the same tarball to N workers. They do it through storage and egress. The pipe does it through the wire.

AWS S3 (cache bucket + egress)Storage you'll overwrite tomorrow + per-pull egress
GitHub Actions cacheYaml keys, runner-specific quirks, 10 GB ceiling
BuildJet / Garnix CI cachesFaster, still per-vendor, still per-byte
Bazel remote cacheExcellent if you're all-in on Bazel; heavy if you're not
Turborepo remote cacheVercel-hosted, monorepo-shaped, opinionated
Earthly satellite cacheAnother daemon, another bucket, another bill
Custom rsync cachesAn NFS box and an SSH key everyone forgets to rotate

use-cases / a-ci-cache-thats-just-two-curl-commands / cta

Two curl commands. One URL. Twenty workers fed.

Read the pipe docs

use-cases / a-ci-cache-thats-just-two-curl-commands / related

Read the others

Sixty containers on one server

One bare-metal box runs dozens to hundreds of Hoody containers. KSM and BTRFS dedup make the marginal cost near zero.

Containers·Snapshots

Onboard a developer with one link

A new engineer joins on Monday. You send one URL. They open it on whatever laptop they have and they're in a fresh container cloned from your developer-baseline snapshot — code, deps, env, seed data, VSCode-in-browser. Writing code in five minutes, not setting up.

Snapshots·Containers·Terminal·Files

API endpoints that materialize on demand

A wildcard exec script catches the call, asks an LLM to write the handler, runs it in a V8 sandbox, and saves the route. The next call is native.

Exec·Agent·Code·Files

Branch computers like Git

Snapshot a running container — files, processes, memory. Restore in seconds. Fork via /copy. Branching, but for the entire machine.

Snapshots·Containers

Real VS Code on your phone

The Code Orchestrator spawns a VS Code instance on the container and serves the editor over a normal HTTPS URL. Any device with a browser can open it. The work lives in the container, not on the device.

Display·Terminal·Files·Containers+1

AI agents that spawn other AI agents

A research agent posts to /api/v1/projects/$PID/containers to start a child container, then calls the child's agent URL like any other HTTP service. Sub-agents spawn their own sub-agents the same way. No orchestrator framework, just URLs.

Agent·Exec·Containers

One sandbox per customer, automatically

An exec script catches your signup webhook, copies a fresh-customer container, and hands the new tenant their own URL. Isolation is the operating system, not a tenant_id column.

Containers·Snapshots·Exec·Files

Wake up to a finished prototype

Hand the agent a paragraph at midnight. It spawns its own containers, snapshots before risky steps, and posts to your notification webhook at sunrise.

Agent·Snapshots·Containers·Browser+2

Emergency production fix from your phone

PagerDuty wakes you. Open the terminal URL on your phone. PATCH the snapshot from before the bad deploy. Production is back. No bastion, no VPN, no laptop.

Terminal·Snapshots·Network

Tail production logs to a URL anyone can curl

One pipe URL. Up to 256 readers. Three engineers tail the same incident at once with no bastion, no Datadog seat, no log forwarder.

Pipe

Push one build to thirty CI workers at once

The build container streams the tarball to a pipe path with ?n=30. All thirty test workers curl the same URL. Bytes go through once, fanned out.

Pipe

Watch your agent think from the coffee shop

Your agent runs at home. You're at a café. Pipe each event of the loop through Hoody Pipe and curl the same path from your phone — the trace lands character by character. No SSH, no dashboard, no upload.

Pipe·Agent

Move 200GB between clouds with two curls

pg_dump | gzip | curl from Frankfurt. curl | gunzip | psql in Singapore. Bytes flow through the pipe with zero disk in the middle.

Pipe

Send a teammate a database state in one line

pg_dump streams straight into their psql. No file uploaded, no link shared, no download. The pipe routes the bytes through.

Pipe

Stream LLM tokens to anything that reads HTTP

Step 3 streams tokens with curl -T -. Step 4 curls the same path. Tokens move generator to consumer at line speed. No SSE plumbing, no broker.

Pipe·Agent

A progress bar your boss can spectate without joining

Append ?progress to the pipe URL. Anyone who opens it gets a live HTML dashboard — bytes, speed, ETA, state. Up to fifty spectators, none consuming a receiver slot, none touching the stream.

Pipe

The webhook fan-out you didn't have to build

Stripe POSTs to a pipe path with ?n=12. Twelve subscribers curl the receiver URL with ?n=12. The pipe holds the event until everyone is connected.

Pipe·Exec

Drag-drop uploads into your script

hoody-pipe serves a web upload form at every path. Drag a file onto the page, your script reads the bytes from stdin. Zero upload code, no S3 bucket, no presigned URLs.

Pipe·Exec

Broadcast a workshop to 200 viewers from your laptop

ffmpeg streams your screen to a pipe path with ?n=200. Each attendee curls the URL into a browser tab. No platform, no logins, no upload.

Pipe

Inter-container IPC without the message broker

Container A writes to a pipe path. Container B reads from the same path. Backpressure is the connection. No Redis, no queue, no broker.

Pipe·Containers

Tail your agent on the train, get pinged when it lands

The agent streams its trace to a pipe path you can curl from your phone. When it finishes, its last act hits hoody-notifications and your phone buzzes. Two URLs and a buzz — no SDK, no client app, no dashboard.

Pipe·Agent·Notifications

A microphone over HTTP, in two terminals

ffmpeg captures the mic, pipes to a URL. The other end curls and plays the audio. No Zoom, no SDK, no signaling server.

Pipe

Five agents, five pipes, one verdict

A panel of five models reviews the same input. Each runs in its own container and streams its verdict to its own pipe path. A judge process curls all five in parallel and tallies the result.

Pipe·Agent·Containers

Replay this morning's incident to the whole team

Snapshot the incident-time logs in hoody-files. Replay them through a Hoody Pipe URL with ?n=8. Eight engineers curl the same path and watch the cascade fire in lockstep — the post-mortem is a synchronized stream, not a Confluence doc.

Pipe·Files

The fastest 'send me that file' you've ever typed

A teammate pings for a 4 GB dump. Slack rejects it, Drive needs a share request. You type curl -T file …; they type curl … > file. The bytes move directly between disks — no upload bar, no link to share.

Pipe

Run a local LLM, serve it to your whole fleet

One GPU runs llama.cpp. Its tokens stream into a pipe path with ?n=50. Fifty containers curl the same URL and split the stream.

Pipe·Daemon

A live metrics dashboard with no metrics backend

Each container's monitoring loop curls a metric to a pipe URL. The dashboard curls the same URL with ?progress and renders the SSE stream.

Pipe

The cron job that deletes itself when you're done

POST a managed cron entry with expires_at set 48 hours out. The job runs on schedule, then removes itself — no reminder, no cleanup PR, no stale entry.

Cron

Snapshot the container right before the nightly migration

A hoody-cron entry that fires at 02:55 UTC, curls the snapshots URL, and names the artifact pre-migration-2026-05-04. Five minutes later the migration runs. If it succeeds, the snapshot sits idle and costs nothing. If it fails, you restore in 30 seconds with a single PATCH.

Cron·Snapshots

A separate crontab for every customer, automatically

Each tenant gets their own container and their own hoody-cron service. Customer A's 9am digest fires on time even when customer B's job hangs for 40 minutes, because they aren't on the same crontab.

Cron·Containers

Wake an agent at 3am, retire it at 4

A nightly cron POSTs a spawn request, the agent does its hour of work, then a second cron tears the container down. The agent exists only when there is work for it to do.

Cron·Agent·Containers

Daily rollups without an orchestrator

Raw events pile up in a sqlite URL. Every night a cron entry curls an exec endpoint, the script runs the rollup SQL, writes the daily table back. No DAG, no Airflow Postgres, no scheduler dashboard.

Cron·SQLite·Exec

A crontab per branch, deployed with the code

Your repo checks in `.hoody/crontab`. The deploy script PUTs that file to the new container's Cron API. Each branch gets its container, its filesystem, its schedule.

Cron·Containers

On-call escalation that ages out with the shift

POST a cron entry with expires_at = shift end. When the shift ends, the entry deletes itself. The next on-call posts their own.

Cron·Notifications

Hourly scrape, daily digest, weekly archive — one container

Three lines in one crontab: hourly browser scrape into SQLite, daily exec digest, weekly archive to files. Flat-rate server, three rhythms, no scheduler service.

Cron·Browser·SQLite·Files

Let your customers BYO their own cron schedule

Customers POST their own 5-field expressions; their crontab lives in their container, isolated. You don't validate against a global queue.

Cron·Containers

Schedule the agent, not the script

A 5-field cron entry curls hoody-agent with a prompt instead of running a fixed script. Today is the last day of the month — the agent figures it out. The data shape changed — the agent figures it out.

Cron·Agent

A heartbeat for the silent jobs

Each cron run POSTs a heartbeat to a notifications endpoint. A second cron checks last-heartbeat and pages on silence. Silence is the alert.

Cron·Notifications

Keep the last 24 hours as 24 snapshots

An hourly cron POSTs a snapshot named with the hour. After 24 hours each new snapshot overwrites yesterday's at the same hour. The 24-floor time machine.

Cron·Snapshots

Replay this morning's webhooks at the same time tomorrow

You captured 30 minutes of real Stripe traffic into a hoody-files folder. One cron entry replays it against staging at 9am every weekday — same volume, same payloads, same time-of-day pressure.

Cron·Files·Exec

Edit your crontab from a phone, in the airport

Open the cron URL on your phone in the gate area. Tap a row, change a single field of the cron expression, hit Save. PATCH lands. The job fires tonight on the new schedule. No SSH session, no jump box, no laptop.

Cron·Terminal

A scheduled digest that fans out to 200 inboxes

Cron at 9am POSTs to an exec script that builds the digest and curls a pipe URL with ?n=200. Two hundred recipients hit the same URL once.

Cron·Exec·Pipe

Mute the flaky job without losing it

PATCH /entries/[id] [ enabled: false ]. The job stays in your crontab waiting to be fixed. No deletion, no rewrite, no lost context.

Cron

An agent that grades yesterday's agents

A nightly cron POSTs to the supervisor agent with yesterday's agent traces from SQLite. The supervisor scores each one. Cron is the supervisor.

Cron·Agent·SQLite

Cleanup jobs that schedule their own retirement

The cleanup script checks if there's anything left to clean. When the directory is empty, it DELETEs its own cron entry. Job's done, job's gone.

Cron·Files

Roll your TLS certificates without an SSH session

Cron weekly: POST to an exec script that runs certbot, posts the new cert to the proxy via PATCH. No shell session, no key, no jump host.

Cron·Exec

A weekly canary that tries to break production

Sunday 7am cron wakes a Hoody Agent in a fresh container against a snapshot of prod. It runs the OWASP top twenty, fuzzes the API, and writes a findings report to a URL by 9am. Container retires.

Cron·Agent·Browser·Snapshots

The hobby-project graveyard you can afford to keep alive

Eleven half-finished side projects on Heroku is eleven dynos at $5–7 each. On Hoody it's eleven containers on one $29 bare-metal box. Idle costs zero, the URL wakes the container in milliseconds, and the chess engine nobody uses still runs.

Containers

A preview environment per pull request, all month

Each open PR gets its own clone of a snapshot. The container wakes when reviewers click the link; idle PRs cost nothing.

Containers·Snapshots

Run a 12-product portfolio from one bare-metal box

Twelve isolated containers, each its own SaaS, share one $49 bare-metal server — a step above the $29 entry tier, chosen here for the RAM headroom fifty containers want. Per-product margins go from negative to nice.

Containers

Kill the staging-server tax

Stop paying for a duplicate of production. Snapshot the prod container, branch staging from it on demand, freeze it back to disk when nobody's testing. Three environments, one machine, one bill.

Containers·Snapshots

Forty client sites, one rent, one dashboard

Each client site lives in its own container; you bill them per-site, you pay the host once. The math finally works for agencies.

Containers·Workspaces

Replace the E2B bill with the bare metal you already rent

Your agents stop renting compute by the second from E2B/Modal/Daytona. They use containers on the box you already have.

Containers·Agent·Exec

Idle staging costs nothing, so staging stops getting deleted

Staging used to die because it was expensive to keep around. When idle is free, staging gets to live — even the one a teammate touched 90 days ago.

Containers·Snapshots

Per-customer sandboxes at fleet scale

Eight hundred isolated customers on three bare-metal servers — one flat-rate monthly bill, no per-tenant meter. Each tenant gets a real container with its own kernel namespace, filesystem, and URL. Idle containers cost nothing on top of the server you already pay for.

Containers·Snapshots·Exec

The CI cache that's not an S3 line item

Cache files live in /files on the box you already rent. Workers PUT and GET tarballs over HTTP. No S3 bucket, no egress, no third vendor — the bytes never leave the box.

Files·Containers

Fifty demo environments for fifty sales calls

Each prospect gets a real, isolated copy of your product seeded with their data. Cloned from a snapshot. Theirs to keep for a week.

Containers·Snapshots

A CI cache that's just two curl commands

The whole mechanic in two shell lines

Produce the cache

Consume the cache

What you stop paying for

No bucket. No egress bill.

No cache action quirks

No key collisions across branches

The cost shape, before and after

Stream once, fan out

Live only in flight

Branches are paths

What this replaces

Read the others

Sixty containers on one server

Onboard a developer with one link

API endpoints that materialize on demand

Branch computers like Git

Real VS Code on your phone

AI agents that spawn other AI agents

One sandbox per customer, automatically

Wake up to a finished prototype

Emergency production fix from your phone

Tail production logs to a URL anyone can curl

Push one build to thirty CI workers at once

Watch your agent think from the coffee shop

Share your screen with a URL, not a meeting invite

Move 200GB between clouds with two curls

Send a teammate a database state in one line

Stream LLM tokens to anything that reads HTTP

A progress bar your boss can spectate without joining

The webhook fan-out you didn't have to build

Drag-drop uploads into your script

Broadcast a workshop to 200 viewers from your laptop

Inter-container IPC without the message broker

Tail your agent on the train, get pinged when it lands

A microphone over HTTP, in two terminals

Five agents, five pipes, one verdict

Replay this morning's incident to the whole team

The fastest 'send me that file' you've ever typed

Run a local LLM, serve it to your whole fleet

A live metrics dashboard with no metrics backend

The cron job that deletes itself when you're done

Snapshot the container right before the nightly migration

A separate crontab for every customer, automatically

Wake an agent at 3am, retire it at 4

Daily rollups without an orchestrator

A crontab per branch, deployed with the code

On-call escalation that ages out with the shift

Hourly scrape, daily digest, weekly archive — one container

Let your customers BYO their own cron schedule

Schedule the agent, not the script

A heartbeat for the silent jobs

Keep the last 24 hours as 24 snapshots

Replay this morning's webhooks at the same time tomorrow

Edit your crontab from a phone, in the airport

A scheduled digest that fans out to 200 inboxes

Mute the flaky job without losing it

An agent that grades yesterday's agents

Cleanup jobs that schedule their own retirement

Roll your TLS certificates without an SSH session

A weekly canary that tries to break production

The hobby-project graveyard you can afford to keep alive

A preview environment per pull request, all month

Run a 12-product portfolio from one bare-metal box

Kill the staging-server tax

Forty client sites, one rent, one dashboard

Replace the E2B bill with the bare metal you already rent

Idle staging costs nothing, so staging stops getting deleted

Per-customer sandboxes at fleet scale

The CI cache that's not an S3 line item

Fifty demo environments for fifty sales calls