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Case study · Mar 2026 – present

ProofMode: prove the process, don’t guess the author

Students keep writing in Google Docs or Word and save lightweight checkpoints in ProofMode as they go. ProofMode turns those checkpoints into a PDF evidence summary with an integrity stamp, so instructors can see how a paper actually came together instead of trusting an AI detector’s guess.

The ProofMode writing app
The live ProofMode app.

The problem

AI-detection tools look at a finished essay and guess whether it “looks like” AI. That’s an arms race: detectors are easy to fool with light editing, and when they’re wrong, honest students are the ones who get accused. A guess after the fact is a weak foundation for academic integrity decisions.

The idea: proof of process

AI detection

Analyzes the final text after it’s submitted. Produces a probability. Can be spoofed, and gives an honest student no way to show their work.

ProofMode

Records the writing process as it happens: timestamped checkpoints, revision metrics and reflection notes, saved in a record the student chooses to share.

How it works

  1. Start once. Add the assignment prompt, title and due date. Templates cover common humanities and business assignments.
  2. Capture checkpoints. After real writing sessions, over days or weeks, paste in the current draft. Each checkpoint is timestamped with character-change metrics, and students can add short reflection notes explaining their choices.
  3. Show revision. ProofMode builds a timeline of change: writing days, how the draft grew and how deeply it was revised.
  4. Export the proof. The server generates a PDF evidence summary with up to five recent checkpoints, reflection notes, revision metrics and an integrity stamp that helps instructors evaluate the process with less guesswork.
  5. Share on the student’s terms. A revocable link (/s/{token}) gives the instructor access, and the student can turn it off at any time.

Architecture

BrowserNext.js 14 · TypeScriptTiptap rich text FastAPIauth · drafts · sharingsecurity headers PostgreSQLFernet-encrypted text ReportLabtimeline PDF JWT + CSRF SQLAlchemy Docker services · managed PostgreSQL · Render

Security and privacy by design

Student writing is personal, so security was a requirement from the start, not an add-on:

PasswordsHashed with Argon2, a modern memory-hard algorithm.
SessionsSigned JWTs in cookies, with CSRF protection on every request that changes data.
Essay textField-level encryption with Fernet before it’s stored, so the database never holds readable essays.
SharingRevocable, token-based links: the student decides who sees the proof, and for how long.
Web hardeningSecurity-header middleware on every response.

Results

What it shows

ProofMode reframes an AI problem instead of fighting it head-on: rather than building a better detector, it changes what gets measured. It also covers the full path from idea to production: product thinking, a full-stack build, security for sensitive data, and deployment.

FastAPI · Next.js 14 · TypeScript · Tiptap · PostgreSQL · SQLAlchemy · Argon2 · JWT · Fernet · ReportLab · Docker · Render

Try ProofMode View the code Back to the 3D site