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EdTech

An assessment platform that holds up on results day

Placeholder case study. Timed assessment delivery engineered for concentrated load, with integrity controls and accessibility treated as requirements rather than settings.

  • Next.js
  • TypeScript
  • Node.js
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  • Kubernetes
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Sample case study — illustrative, not a delivered client engagement

Lumen Learning Group is an invented company used to demonstrate our case-study format and our approach to this kind of work. The technical detail reflects how we would genuinely deliver it; the client name is fictional and the figures under Results are design targets rather than measured outcomes.

Client

Lumen Learning Group

Illustrative further-education provider — PLACEHOLDER CONTENT

Industry
EdTech
Year
2026

The business challenge

PLACEHOLDER — replace with the real engagement narrative. The illustrative situation: an assessment platform that worked comfortably day to day fell over during submission deadlines and results releases, when a term of traffic arrived in twenty minutes. Failures were highly visible, and the accessibility obligations attached to the sector had never been formally assessed.

Objectives

  • PLACEHOLDER — Survive deadline and results-day load without degradation
  • PLACEHOLDER — Meet accessibility obligations for assessment delivery
  • PLACEHOLDER — Give assessors marking and moderation tooling they trust
  • PLACEHOLDER — Integrate with the student information system and single sign-on
  • PLACEHOLDER — Make each release safe enough to ship inside term time

Discovery and strategy

What we did before writing code

  • PLACEHOLDER — Modelled real submission traffic from two prior deadlines
  • PLACEHOLDER — Load tested the existing platform to find where it actually broke
  • PLACEHOLDER — Audited the assessment interface against WCAG 2.2 AA
  • PLACEHOLDER — Interviewed assessors about where marking time was lost
  • PLACEHOLDER — Reviewed integrity requirements with the academic team

Solution

What we built

  • PLACEHOLDER — Submission pipeline

    Replace with real detail. Submissions accepted through a durable queue so a downstream slowdown delays processing rather than rejecting a student’s work.

  • PLACEHOLDER — Timed delivery

    Replace with real detail. Server-authoritative timing with tolerance for connection loss, so a dropped network does not cost a candidate their attempt.

  • PLACEHOLDER — Marking and moderation

    Replace with real detail. Rubric-based marking with moderation sampling and reviewer calibration reporting.

  • PLACEHOLDER — Institutional integration

    Replace with real detail. LTI 1.3, single sign-on and student information system synchronisation.

  • PLACEHOLDER — Integrity controls

    Replace with real detail. Session controls and audit logging designed to support the institution’s academic integrity policy.

  • PLACEHOLDER — Capacity planning

    Replace with real detail. Autoscaling tuned against modelled peaks, with a rehearsed runbook for results day.

Architecture

How it fits together

PLACEHOLDER — Assessment platform architecture

Replace with the real architecture. The illustrative shape: submission accepted and durably queued at the edge of the system, so peak load never reaches the slowest component synchronously.

  1. Assessment interfaceTimed delivery, accessible by design
  2. Submission queueDurable intake with retries
  3. Processing workersAutoscaled marking and grading
  4. Institutional integrationLTI 1.3, SSO, SIS sync
  5. AnalyticsProgression and outcome reporting
  6. Audit logIntegrity and appeals evidence

Design approach

Decisions in the interface

  • PLACEHOLDER — Designed the candidate interface to be readable at 400% zoom
  • PLACEHOLDER — Made time remaining and save state permanently visible
  • PLACEHOLDER — Reduced the marking screen to the decision the assessor is making
  • PLACEHOLDER — Verified with screen reader users before the first live assessment

Development process

How the work ran

  • PLACEHOLDER — Load tests run against modelled peak on every release candidate
  • PLACEHOLDER — Characterisation tests written around existing grading behaviour first
  • PLACEHOLDER — Results-day runbook rehearsed in a non-production environment
  • PLACEHOLDER — Releases scheduled outside assessment windows by policy

Technology stack

What it runs on

  • Next.js
  • TypeScript
  • Node.js
  • PostgreSQL
  • Redis
  • ClickHouse
  • Kubernetes
  • AWS

Challenges resolved

What went wrong, and what we did

Every project has these. A case study that omits them is a brochure.

  • PLACEHOLDER — Submission spikes overwhelmed processing

    Replace with real detail. Accepting into a durable queue decoupled intake from processing, so peak load delays marking rather than rejecting submissions.

  • PLACEHOLDER — Timing disputes had no evidence

    Replace with real detail. Server-authoritative timing with a full audit trail gave the appeals process something to examine.

  • PLACEHOLDER — Accessibility findings arrived late

    Replace with real detail. Automated checks moved into the pipeline so regressions fail the build rather than surfacing in an audit.

Results

Objectives and design targets

Because this is a sample case study, these are the objectives and design targets agreed in scope — not measured business results.

  • PLACEHOLDER — Peak capacity

    Target only

    Placeholder. Replace with a measured, verifiable outcome or remove.

  • PLACEHOLDER — Accessibility

    WCAG 2.2 AA

    Placeholder conformance target for candidate-facing screens.

  • PLACEHOLDER — Release cadence

    In-term releases

    Placeholder design target from the engagement scope.

Client feedback

In their words

Placeholder quote

This quote is sample content shown to demonstrate the layout. It is not attributable to a real person or organisation and will be replaced only with a genuine, approved testimonial.

  • “PLACEHOLDER — replace with a real, approved client quote. This text exists only to demonstrate the layout.”
    Placeholder namePlaceholder role (illustrative)

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