Attribution window is configurable, not hard-coded

Attribution windows determine how far back from a conversion you look for a causal email touchpoint. A 7-day window and a 30-day window produce materially different revenue attribution numbers for the same campaign — especially for products with long consideration cycles. If the window is a magic number hard-coded in four different query files, changing your attribution model to match your actual sales cycle requires a multi-file search-and-replace with no guarantee you caught every instance. This is an iso-25010:2011 maintainability failure: the system cannot adapt to a known parameter without engineering effort and regression risk.

Extract the attribution window to a single named constant sourced from an environment variable so it can be changed in one place without touching query logic:

// lib/attribution/config.ts
export const ATTRIBUTION_WINDOW_DAYS = parseInt(
  process.env.ATTRIBUTION_WINDOW_DAYS ?? '30',
  10
)

export function getAttributionWindowStart(): Date {
  return new Date(Date.now() - ATTRIBUTION_WINDOW_DAYS * 24 * 60 * 60 * 1000)
}

Import getAttributionWindowStart() in every attribution query. Set ATTRIBUTION_WINDOW_DAYS in your environment config (.env.local, Vercel env vars) so it's tunable without a deploy. Document the chosen value and rationale in a comment near the constant.

• ID: attribution-window-configurable

• Severity: low

• What to look for: Look at the attribution window used when computing which touchpoints receive credit for a conversion. Check whether the attribution window (e.g., 7 days, 30 days) is a configurable constant or configuration value, versus being hard-coded as a magic number scattered across multiple queries. The ability to adjust the attribution window without code changes is important as you refine your model to match your actual sales cycle length.

• Pass criteria: Attribution window is defined as a named constant, environment variable, or database configuration that can be changed without modifying query logic. The value is referenced from a single definition. Count all files that reference the attribution window value — no more than 1 source definition should exist.

• Fail criteria: Attribution window is hard-coded as a magic number (e.g., 30 or 2592000) directly in query logic with no named constant. Multiple places have different hard-coded values.

• Skip (N/A) when: Attribution windows are not used (the project does not perform attribution).

• Detail on fail: Example: "Attribution window hard-coded as 30 in 4 different query files — changing the window requires editing multiple files" or "Magic number 2592000 (30 days in seconds) appears in queries without explanation"

• Remediation: Extract to a named constant:

  // lib/attribution/config.ts
  export const ATTRIBUTION_WINDOW_DAYS = parseInt(
    process.env.ATTRIBUTION_WINDOW_DAYS ?? '30',
    10
  )
  
  // Use in queries
  import { ATTRIBUTION_WINDOW_DAYS } from '@/lib/attribution/config'
  
  function getWindowStart(): Date {
    return new Date(Date.now() - ATTRIBUTION_WINDOW_DAYS * 24 * 60 * 60 * 1000)
  }