JD Studio — Private tools for files, mail and money.

01 / files

Gooi.

Send it. Keep it private.

Zero-knowledge file transfer up to 5 GB, no account needed. Encryption happens in your browser before upload, so nobody along the way can read the file, and an interrupted upload resumes on its own.

AES-256-GCM
≤ 5 GB
no account
auto-resume

Open gooi.io

Ready to use · no account

Gooi encrypted file-transfer dropzone — Encrypted before it leaves your browser.

02 / mail

Jaymail.

Your mailbox, calmer.

Mail, calendar and contacts in one place, on web, iOS and native Android. JMAP-native, so it talks to your Stalwart mailbox directly: push instead of polling, undo send, and remote images blocked until you trust the sender.

web · iOS · Android

JMAP-native
no ads, no trackers
undo send

Explore Jaymail

Early access · for Stalwart mailboxes

Actual Jaymail inbox on iOS, using fictional demo mail. — Actual interface · DEMO DATA · iOSView full size

03 / investing

Pertalo.

See what changed. Know why.

A portfolio tracker that turns your brokers' transactions into one story per period: what you put in, what the market did, and where the result came from. Bitvavo, Trading 212 and Bybit by API; DEGIRO, Trade Republic and Coinmerce by CSV. Runs on your own server.

period stories
index comparison in euros
box 3 report

Ask about Pertalo

Private alpha · enquire · not advice

Actual Pertalo portfolio interface with a value chart and period explanation, using fictional demo data. — Actual interface · DEMO DATAView full size

04 / bookkeeping

Moneybarn.

Your books. Your server.

Self-hosted bookkeeping for Dutch businesses: invoices, quotes, purchases, bank imports and the VAT return in one place, on a real double-entry ledger. Built to replace Moneybird without breaking the scripts and connections you already have.

Moneybird-compatible API
double-entry ledger
Dutch VAT

Ask about Moneybarn

Private deployment · enquire

Already using it? Sign in

Actual Moneybarn overview with revenue, bank, tasks and VAT for the fictional demo company Demo B.V. — Actual interface · DEMO DATAView full size

05 / hosting

Mailbarn.

A dependable home for your email.

Managed email hosting for one to five mailboxes on your own domain: spam filtering, daily backups with a rehearsed restore, and a human to write to. Jaymail included, other clients welcome.

your domain
1–5 mailboxes
JMAP · IMAP · SMTP

Visit Mailbarn

Private pilot · invite only

Databarn glass floor showing the cabling beneath — Databarn is the studio's own datacenter in Amsterdam. Mailbarn and Gooi run on this floor.

The studio · Amsterdam

From the first pixel
to the last packet.

JD Studio is the software studio of Jordy Dost. One person designs the interfaces, writes the software and runs the services, on the studio's own Databarn infrastructure in Amsterdam.

One person.Design, code and operations, end to end.

Own datacenter.Databarn, Amsterdam. Gooi and Mailbarn run here.

Nothing to accept.0 third-party requests, 0 cookies, no cookie banner.

Privacy in the product

Gooi encrypts files in your browser before upload. Jaymail blocks remote images until you trust the sender.

Files & mail

Numbers you can follow

Pertalo explains every period as money in, market result and money out. Moneybarn refuses an unbalanced journal entry at the database.

Investing & bookkeeping

Open by design

JMAP for mail, vCard and iCalendar for people and dates, CAMT and MT940 for bank files, and Moneybird's own API for bookkeeping. Familiar standards, room to choose.

Built on open foundations

With a touch of orange.

In progress

Now shipping.

Small tools. Ongoing work.

Moneybarn

bookkeeping

Moneybird migrations now verify totals and ledger balances before the switch.

Jaymail

mail

Native Android v1 is complete; store release is next.

Pertalo

investing

Portfolio periods now explain their result.

Mailbarn

hosting

Private pilot in preparation.

Gooi

files

Encrypted transfers recover automatically after an interruption.