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Edtech · AI Writing-Correction SaaS

Pluma

AI writing correction that teaches language learners why a sentence is wrong, and how to fix it.

Input → Correct → ExplainCorrection Workflow
OpenAI-PoweredGrammar Engine
Daily Tasks + ScoringLearning System
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Pluma is an AI-powered writing-correction platform built for language learners who need more than red underlines. Learners submit text and get structured corrections paired with categorized explanations, a clarity score, and daily practice tasks, turning every mistake into a lesson. We took the product from its Figma design through to a working Bubble build, wiring an OpenAI correction pipeline into a learning-focused UX that guides users through consistent practice routines.

Product screens

A look inside

Key Results Achieved

A grammar checker that behaves like a tutor

Structured feedback, category-level scoring, and daily practice, delivered as a lightweight, scalable Bubble SaaS.

Score-BasedCorrection Feedback
Category-LevelMistake Detection
Task-BasedDaily Practice Loop
The approach

Challenge & solution

The challenge

Most grammar tools tell learners what is wrong. Pluma had to tell them why, and keep them practicing.

Business challenges

  • Existing tools highlight errors but rarely explain them, so learners correct a sentence without understanding the underlying rule.
  • Language progress depends on consistent practice, and one-off corrections give users no reason to return day after day.
  • A generic checker reads as a utility; Pluma needed to feel like a structured learning experience to stand as a language-learning SaaS.

Technical challenges

  • Free-form OpenAI responses had to be shaped into consistent, structured output, corrections, explanations, and categories the interface could render reliably.
  • Corrections needed a scoring model so learners could see measurable clarity and accuracy rather than pass/fail feedback.
  • Mistakes had to be classified into categories and visualized, not shown as a flat list of edits.
  • A daily task workflow with completion tracking had to sit on top of the correction engine to drive repeat practice.

Our solution

We translated the Figma design into a working Bubble application and built the correction engine around learning, not just editing.

Core features delivered

  • AI Grammar Correction PipelineAn OpenAI-powered engine evaluates submitted text and returns structured corrections, driven by an optimized prompt pipeline behind the scenes.
  • Correction + Explanation OutputEvery correction is paired with a categorized explanation and improvement guidance, so learners see the reasoning, not just the fix.
  • Category-Level Detection & ScoringMistakes are classified by category and scored, giving learners a clear read on where their writing is strong and where it needs work.
  • Daily Task Learning WorkflowStructured daily writing exercises with completion indicators guide users through consistent practice routines.
  • Score-Based Result ScreensCorrection results surface a score alongside categorized feedback, framing progress as measurable and repeatable.
  • Mobile-Responsive InterfaceThe learning interface is built to work across screen sizes so practice fits into everyday routines.
Under the hood

Architecture & technical build

Pluma runs on Bubble, with OpenAI wrapped in a structured prompt pipeline and Google OAuth handling sign-in.

Architecture overview

  • A Bubble frontend renders the correction interface, daily task screens, and category-based feedback visualization.
  • An OpenAI correction pipeline converts free-form text into structured corrections, explanations, and category tags through an optimized prompt design.
  • Correction scoring and daily task completion logic sit in Bubble workflows, tracking practice and feedback over time.
  • Google OAuth provides authentication and low-friction onboarding into the learning environment.

Key technical components

Correction EngineOpenAI-driven pipeline that turns raw input into structured, categorized correction output rather than plain error highlighting.
Scoring & Feedback LogicBubble workflows that score corrections and assemble category-level feedback for the result screen.
Daily Task SystemTask-based learning workflow with completion indicators that sequences users through daily writing exercises.
Auth & OnboardingGoogle OAuth login for secure, one-tap access into the platform.

Tech stack

Bubble.ioOpenAI (Grammar Correction Pipeline)Google OAuthBubble Backend WorkflowsFigma → Bubble Design Workflow
Outcomes

Results & impact

Early outcomes

  • Delivered a correction-to-explanation pipeline that treats every mistake as a teaching moment, not just an edit.
  • Shipped a daily task workflow with completion tracking to keep learners practicing consistently.
  • Built category-level scoring so users can see, at a glance, where their writing is improving.

Business impact

  • Positions Pluma as a structured learning product rather than a commodity grammar checker.
  • Establishes a lightweight, scalable Bubble SaaS foundation ready to extend with new languages, exercises, and feedback categories.
More work

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The last step

Have an AI learning product in mind?

Velcod builds AI-powered SaaS like Pluma, from Figma design through to a working Bubble product with structured OpenAI pipelines and learning-focused UX. Tell us what you want to build, and we will map the path to launch.

Book a Free Strategy Call →

3-week launch · Fixed pricing · Senior team