Cloud storage · checked 2026-10-19

Can I vibecode Dropbox Plus?

KINDA· weekend project

The sync core of Dropbox for one person is a file watcher, a hash index and an object store, and an agent can wire those into a working daemon in a weekend. The weekend goes on what makes sync trustworthy: two laptops editing the same file, deletes that must not spread by accident, large uploads that stop halfway, and file watching that behaves differently on each OS. Phones and online-only placeholder files are out of reach for one prompt, and storage costs what it costs: 2 TB on Backblaze B2 is about $14 a month, more than Plus, so a build only saves money if you store far less than 2 TB.

$11.99/moprice

$144you'd save a year

weekendbuild time

—people replaced it

Before you start

What you need on hand.

DifficultyAdvanced · Real infrastructure or OAuth work.

TimeA weekend; conflict and restore testing take longest

Claude Code, Codex or CursorAny of them can run the prompt.
Node.js 22better-sqlite3 compiles a native module, so build tools must be installed.
An S3-compatible bucketBackblaze B2 starts at $6.95 per TB a month and the first 10 GB are free; MinIO works on your own disk.
A server with a public HTTPS addressA small VPS or a home machine with a tunnel; share links must open for people without accounts.
Test files you can afford to loseRun it on a copy of your Dropbox folder first.

Before you buildDropbox Basic gives 2 GB for free, and Syncthing syncs your own devices at no cost. If you don't need share links, start with Syncthing.

1. Install one agent: Claude Code, Codex, Cursor.
2. Make an empty folder and open it in the agent.
3. Paste the prompt below, press enter, and answer its questions as it builds.

The prompt

Build me a personal folder-sync tool to replace Dropbox Plus. Requirements:

- Node.js 22 + TypeScript in one repo: a Fastify server on http://localhost:4870 and a
CLI daemon `dropsync` that watches ~/Sync with `chokidar` and syncs it to the server.
- File content lives in an S3-compatible bucket (Backblaze B2 or MinIO) through
`@aws-sdk/client-s3`; endpoint, key and bucket come from .env. Split files into 4 MiB
chunks stored under their SHA-256, so only changed chunks upload.
- The server keeps the index in better-sqlite3 at ./data/index.db: path, version number,
chunk list, mtime and a deleted flag. Devices pull changes with GET /changes?since=<cursor>
every 30 seconds and write files through a temp file plus rename.
- Conflicts: if a file changed on two devices since the last sync, keep both and rename the
newer one to "name (conflict 2026-10-19 laptop).ext". Never overwrite silently.
- Versions: keep every old version for 30 days. `dropsync history <path>` and
`dropsync restore <path> <version>`; deletions go to a trash list purged after 30 days.
- `dropsync share <path> --days 7` prints https://<host>/s/<token>; the token is random,
stored hashed, and the server redirects to a presigned download URL.
- A web page at / lists files, downloads them and shows history. One password in .env,
signed-cookie session. A `.dropsyncignore` file uses gitignore syntax.
- Tests with `vitest`: chunking, conflict naming, restore, and an integration test that
syncs two temp folders through a MinIO container.
- Single user. No accounts, no telemetry, local-first. Outbound calls: your bucket only.
- Out of scope: mobile apps, online-only placeholder files, real-time co-editing, PDF
editing and signatures, sharing between accounts.
- README: HTTPS with Caddy, the storage bill (2 TB on B2 is about $14 a month, more than
Dropbox Plus), and a warning to keep Dropbox for a month while you test restores.

Opens your agent with the prompt filled in, you press enter. Or copy it and paste it into an empty folder.

Share on X

Max MiskowSponsoredAI agents, automations and MVPs, built for your company.Visit site ›

Then keep going

Next prompts, same folder.

The first prompt builds the core. Run these one at a time in the same folder to grow it into your own Dropbox Plus.

Extend the sync tool in this folder. Requirements:

- Encrypt each chunk on the device with libsodium secretbox before upload; the key is
  derived with argon2id from a passphrase and a random salt stored in ~/.dropsync/key.json.
- Store chunks under the SHA-256 of the plaintext HMACed with a key derived from the
  passphrase, so the bucket sees neither contents nor plain hashes.
- The share-link flow decrypts on the server, so it needs the passphrase in .env; document
  the trade-off.
- Add a test that a wrong passphrase fails cleanly, and update the README.

Add phone uploads to the sync tool in this folder. Requirements:

- A /upload page that works as an installable PWA with a Web Share Target, so photos can
  be shared to it from the phone's share sheet.
- Uploads go in chunks with resume after a dropped connection and land in
  ~/Sync/Phone/<yyyy-mm>/ on the server's own device record.
- Show progress and a list of recent uploads; the page is behind the existing password.
- Out of scope: background upload while the page is closed.
- Update the README.

Add selective sync to the sync tool in this folder. Requirements:

- A .dropsyncfolders file lists the server folders each device pulls; everything else is
  indexed but not downloaded.
- `dropsync fetch <path>` downloads one folder on demand and `dropsync evict <path>` removes
  the local copy only after confirming the server has it.
- A deletion on a device that doesn't hold a folder must never delete it on the server.
- Add tests for those cases and update the README.

What you lose

Phone and tablet apps with camera upload and offline files
Files that show in the folder but stay online-only until you open them
Share links and folders that other people open and comment on without setup
Transfers of up to 50 GB, PDF editing, signatures and Replay video review
A 30-day restore for the whole account, backed by Dropbox's data centres rather than one bucket

Why people still pay

People pay for sync they stop thinking about: it works on every device they own, survives sleep, flaky Wi-Fi and big folders, and the person receiving a link doesn't need to install anything. On Linux in particular, Dropbox is one of the few big cloud services with a native client.

Moatexecution polish integrations infrastructure scale

Do the math

Dropbox Plus or your own copy?

Over

Your usage

Count my time12h ×$/h

Dropbox Plus, 1 yr$144

Your own copy, 1 yr$100running + build session

You keep$44pays for itself in 3 months

Estimate · Storage is the cost: Backblaze B2 lists $6.95 per TB a month, so 200 GB is about $1.40 and 2 TB about $14, plus a small VPS if you don't have a home server. The build is token usage on your agent plan.

Leaving Dropbox Plus

Take your data, then cancel.

1 · Take your data out of Dropbox Plus

1For a large account, install the desktop app and let it sync the folders you need to the computer; Dropbox recommends it over the browser for big downloads.
2From dropbox.com, open the folder, use its menu to download, and Dropbox sends a .zip. A folder must be under 250 GB and contain fewer than 10,000 files for that to work.
3Single files have no size limit when downloaded.
4Online documents and anything stored only in the cloud: we didn't find an export procedure in what we read, so open them and save copies.

2 · Cancel Dropbox Plus

1Log in at dropbox.com, click your avatar at the bottom left and open Manage account.
2Click Cancel plan at the bottom of the page, pick a reason and follow the prompts.
3Check the Billing tab for a "Plan downgrade scheduled" notice and the confirmation email.
4No Cancel plan button? Then you probably bought through a phone's app store: cancel it there.

The account moves to Basic at the end of the billing cycle and you aren't charged again.
Over 2 GB on Basic you can lose syncing, uploading and sharing, and if you stay over, Dropbox may delete files you own, least recently modified first. It emails warnings first.
Shared folders count toward your quota; leaving them frees space.
Deleted files stay in the Deleted files tab for 30 days. Run your replacement for a month before cancelling, and test a restore.
The Dropbox help article doesn't state a refund policy; it points to a separate refund page.

Checked 2026-10-19 against Dropbox Plus's docs: 1, 2, 3, 4

The escape hatch

Don't feel like building it? These are already free.

SyncthingOpen sourceMPL-2.0 peer-to-peer folder sync between your own devices with no central server; no share links and no web file browser.★ 90k · active Oct 2026 · one-click install
Windows, mac, Linux, AndroidVisit ↗NextcloudOpen sourceAGPL-3.0 self-hosted cloud with sync clients, share links, versions and a large app store; a PHP stack to look after.★ 37k · active Oct 2026 · docker to self-host
Web, Windows, mac, Linux, iOS, AndroidVisit ↗SeafileOpen sourceLibrary-based file sync and sharing server with a free Community Edition; some features sit in the paid Professional edition.★ 15k · active Oct 2026 · docker to self-host
Web, Windows, mac, Linux, iOS, AndroidVisit ↗

All 4 free alternatives to Dropbox Plus ›

The numbers

Dropbox Plus pricing

Plan	Monthly	Annual, per month	What you get
Basic	$0	$0	2 GB of storage, file storage and sharing.
Plus	$11.99	$9.99	For one person: 2 TB, 30 days to restore deleted files, transfers up to 50 GB, PDF editing and signing, Dropbox Replay with 4 uploads, import from other cloud services.
Standard	$18/user	$15/user	From 1 user, storage starts at 3 TB for the team, 180 days of restore history, transfers up to 100 GB, team folders, admin console, branded and password-protected links, AI features for select teams.
Advanced	$30/user	$24/user	From 3 users, storage starts at 15 TB for the team, one year of restore history, end-to-end encryption, audit logs, SSO and compliance tracking.
Enterprise	custom	—	Custom security integrations and dedicated support.

Free tier: 2 GB total. Plus is the cheapest way to get more space; the next step is a team plan that starts at 3 TB.
Billing: Monthly or yearly; the yearly toggle drops Plus from $11.99 to $9.99 a month. The page shows a Buy now button for Plus and a free trial only on the team plans. Taxes are extra. A plan bought through a phone's app store has to be cancelled there.
Hidden costs: Plus allows 3 signature requests a month and 4 Replay uploads. More than 2 TB means a team plan, from $18 a user a month billed monthly. Going back to Basic with more than 2 GB stored can lock syncing and, in the end, delete files.
Source: www.dropbox.com

Also on the list

Google One$1.99/mo · Cloud storageNOT REALLY

iCloud+$0.99/mo · Cloud storageNOT REALLY

Obsidian Sync$5/mo · Notes & knowledgeKINDA

Questions

Dropbox Plus, briefly

Not answered here? Tell us and we'll add it.

Ask a question ›

Basic is free with 2 GB of storage to store and share files.

Kinda. The core is a weekend build with the prompt on this page, but real gaps remain: Phone and tablet apps with camera upload and offline files, Files that show in the folder but stay online-only until you open them.

About $11.99 a month on the Plus plan, $143.88 a year (checked 2026-10-19).

Phone and tablet apps with camera upload and offline files; Files that show in the folder but stay online-only until you open them; Share links and folders that other people open and comment on without setup; Transfers of up to 50 GB, PDF editing, signatures and Replay video review; A 30-day restore for the whole account, backed by Dropbox's data centres rather than one bucket. If any of those matter to you, keep paying.