Let Customers Upload Spreadsheets Without Sending the Spreadsheet to Us

“Upload your spreadsheet” is a convenient feature.

It is also a sentence that can make a security-conscious customer ask a very reasonable follow-up:

Where does the spreadsheet go?

With Bootstrapware Importer, the answer is simple:

The file contents stay in the browser.

Bootstrapware does not need the rows

The importer component needs to know how your import is configured: expected fields, field labels, validation rules, and the published configuration revision (plus optional display title from branding).

It does not need a copy of the customer's spreadsheet.

Parsing, column mapping, validation, preview, duplicate detection, and normalization happen client-side.

When the import is complete, the normalized rows are returned to your application through onComplete().

Your application sends them to your backend.

What Bootstrapware can receive

In hosted mode the managed service may receive operational metadata such as:

importer ID
session ID
file type
valid row count
invalid row count
duration

It does not receive:

filename
spreadsheet contents
cell values
parsed rows
normalized rows

That boundary is part of the product design, not an optional privacy mode.

Why this is useful commercially too

Privacy architecture is not only a compliance concern.

It makes your sales conversation easier.

Instead of explaining temporary storage regions and retention windows for spreadsheet uploads, you can explain:

“The import UI is provided by Bootstrapware. The spreadsheet contents are processed locally and go from your browser to our application backend.”

That is a much simpler system to reason about.

You still own your own data handling

Once onComplete() returns the normalized rows, your application's own privacy and security model takes over.

Bootstrapware does not make your database writes safe for you.

You still need authentication, authorization, backend validation, rate limits where appropriate, secure storage, and your own retention policy.

Bootstrapware's job is narrower: provide the production spreadsheet-import workflow without becoming another place your customers' spreadsheet contents are stored.