durablecomputer

The computer that outlives its hardware.

Give each agent its own machine. Ask for work in one sentence; get back a link you can open. Close your laptop. Nothing dies.

stateeverything saved · gitdoes not movebay 01 · hetzner · fsn1$0.12/hrbay 02 · vultr · ewr$0.19/hrbay 03 · your metal · rack 4$0.00/hrrunningcmp_7df8216 vcpu · 64 GiB

fig. 01 — one computer moving across three providers. its memory stays put; only the computer moves.

machine recordrev 7
handle
cmp_7df82· constant
status
running
vcpu
16
memory
64 GiB
disk
40 GiB nvme
uptime
3:12:07· never resets
region
fsn1
provider
hetzner
price
$0.12/hr

The computer is not the server.

When the server it is running on disappears at 2 AM, your agent does not notice. The server is just a place the computer happens to be: when it dies, gets expensive, or something faster shows up, the computer moves and keeps working.

your work
saved to git, continuously
the computer
an identity, not a box
the server
swappable at any moment
your setup
travels with the computer
cmp_7df82the computer · durablenot attachednothing sharedsrv-1disposablesrv-2disposablesrv-3disposablethe servers · anyone's, anywhere, replaceable at will

fig. 02 — the two planes. nothing above depends on anything below.

It remembers everything.

Leave on Tuesday, come back Thursday: same files, same session, same conversation. Every computer keeps a diary of what happened to it, and you can rewind to any moment in it.

teventrecord
09:14createdborn with 16 cores and 64 GB of memory
09:41snapshotsaved a copy of itself before a risky change
09:42forksplit into two copies to try two ideas at once
10:03resizeborrowed 32 cores for a heavy build
10:11movefound faster hardware and moved itself
11:26hibernatewent to sleep to stop costing money
14:02resumewoke up exactly where it left off

fig. 03 — one computer's working day, in its own words. the 14:02 wake-up is the same session that went to sleep at 11:26.

One call. Four verbs.

Say what you need: this much power, this much memory, what to optimize for. It finds a home for it. You never pick a company, a datacenter or a server.

$ dc upboots the daemon and the console
agent.tssdk
const computer = await durable.computers.create({
  cpu: 16,
  memory: "64gb",
  optimize: "compile-per-dollar",
});

await computer.exec(agent);
await computer.resize({ cpu: 32 });
const experiment = await computer.fork();
await computer.hibernate();

Close the laptop. Nothing is lost.

A session can die a hundred ways: the laptop sleeps, the server vanishes, the wrong window gets closed. The work finishes anyway, and the link arrives like nothing happened.

recovery.loglive replay

fig. 04 — a crash, replayed. red is the kill; blue is what survived it. our test suite does this to every build.

time we add to your agent0.5 s
from ask to an open link24 s
work lost to a crash0
everything saved on shutdown30 s
measured, 0.44–0.68 s across suite runs · wall clock, cold preview included · interrupted work replays at boot, test-enforced · work in progress pushed to git before stop

Priced like a market. Because it is one.

You never shop for a server again. Say what to optimize; the router keeps choosing, and keeps re-choosing when prices move.

provider$/hrbuild timeavailability
hetzner ccx0.1841 s98%
vultr hf0.3129 s94%
do cpu-opt0.3738 s99%
dc metal0.1427 s91%routed here

fig. 05 — sample market. the router chose the last row because it was asked for the cheapest fast builds.

Pricing.

on your laptop
free
forever. everything runs on your own machine.
hosted
$0.06/hr
2 cores · 4 GB, billed per second. asleep, it only pays for storage.
your own servers
5%
on top of what your provider charges you. never a markup on AI tokens.

Tonight's hardware is temporary. Your computer isn't.