From 169418ce2800ad19189a69becf246ec77d4a2630 Mon Sep 17 00:00:00 2001
From: Yostra <straya.mark@gmail.com>
Date: Fri, 27 Feb 2026 13:33:33 +0100
Subject: [PATCH 1/3] compute order based on deps

---
 packages/sync-engine/src/resourceRegistry.ts  | 30 +++---------
 .../src/utils/computeResourceOrder.ts         | 49 +++++++++++++++++++
 2 files changed, 57 insertions(+), 22 deletions(-)
 create mode 100644 packages/sync-engine/src/utils/computeResourceOrder.ts

diff --git a/packages/sync-engine/src/resourceRegistry.ts b/packages/sync-engine/src/resourceRegistry.ts
index f5b8bd99..f61042ef 100644
--- a/packages/sync-engine/src/resourceRegistry.ts
+++ b/packages/sync-engine/src/resourceRegistry.ts
@@ -1,6 +1,7 @@
 import Stripe from 'stripe'
 import type { ResourceConfig } from './types'
 import type { SigmaSyncProcessor } from './sigma/sigmaSyncProcessor'
+import { computeResourceOrder } from './utils/computeResourceOrder'
 
 export type StripeObject =
   | 'product'
@@ -25,11 +26,10 @@ export type StripeObject =
 
 // Resource registry - maps SyncObject → list/retrieve operations
 // Upsert is handled universally via StripeSync.upsertAny()
-// Order field determines sync sequence - parents before children for FK dependencies
+// Order field [computed] determines sync sequence - parents before children for FK dependencies
 export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, ResourceConfig> {
-  const core: Record<StripeObject, ResourceConfig> = {
+  const core: Record<StripeObject, Omit<ResourceConfig, 'order'>> = {
     product: {
-      order: 1,
       tableName: 'products',
       dependencies: [],
       listFn: (p) => stripe.products.list(p),
@@ -38,7 +38,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: true,
     },
     price: {
-      order: 2,
       tableName: 'prices',
       dependencies: ['product'],
       listFn: (p) => stripe.prices.list(p),
@@ -47,7 +46,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: true,
     },
     plan: {
-      order: 3,
       tableName: 'plans',
       dependencies: ['product'],
       listFn: (p) => stripe.plans.list(p),
@@ -56,7 +54,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: true,
     },
     customer: {
-      order: 4,
       tableName: 'customers',
       dependencies: [],
       listFn: (p) => stripe.customers.list(p),
@@ -67,7 +64,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
         'deleted' in customer && customer.deleted === true,
     },
     subscription: {
-      order: 5,
       tableName: 'subscriptions',
       dependencies: ['customer', 'price'],
       listFn: (p) => stripe.subscriptions.list(p),
@@ -81,7 +77,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
         subscription.status === 'canceled' || subscription.status === 'incomplete_expired',
     },
     subscription_schedules: {
-      order: 6,
       tableName: 'subscription_schedules',
       dependencies: ['customer'],
       listFn: (p) => stripe.subscriptionSchedules.list(p),
@@ -92,7 +87,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
         schedule.status === 'canceled' || schedule.status === 'completed',
     },
     invoice: {
-      order: 7,
       tableName: 'invoices',
       dependencies: ['customer', 'subscription'],
       listFn: (p) => stripe.invoices.list(p),
@@ -103,7 +97,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       isFinalState: (invoice: Stripe.Invoice) => invoice.status === 'void',
     },
     charge: {
-      order: 8,
       tableName: 'charges',
       dependencies: ['customer', 'invoice'],
       listFn: (p) => stripe.charges.list(p),
@@ -115,7 +108,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
         charge.status === 'failed' || charge.status === 'succeeded',
     },
     setup_intent: {
-      order: 9,
       tableName: 'setup_intents',
       dependencies: ['customer'],
       listFn: (p) => stripe.setupIntents.list(p),
@@ -126,7 +118,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
         setupIntent.status === 'canceled' || setupIntent.status === 'succeeded',
     },
     payment_method: {
-      order: 10,
       tableName: 'payment_methods',
       dependencies: ['customer'],
       listFn: (p) => stripe.paymentMethods.list(p),
@@ -135,7 +126,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: true,
     },
     payment_intent: {
-      order: 11,
       tableName: 'payment_intents',
       dependencies: ['customer', 'invoice'],
       listFn: (p) => stripe.paymentIntents.list(p),
@@ -146,7 +136,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
         paymentIntent.status === 'canceled' || paymentIntent.status === 'succeeded',
     },
     tax_id: {
-      order: 12,
       tableName: 'tax_ids',
       dependencies: ['customer'],
       listFn: (p) => stripe.taxIds.list(p),
@@ -155,7 +144,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: true,
     },
     credit_note: {
-      order: 13,
       tableName: 'credit_notes',
       dependencies: ['customer', 'invoice'],
       listFn: (p) => stripe.creditNotes.list(p),
@@ -166,7 +154,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       isFinalState: (creditNote: Stripe.CreditNote) => creditNote.status === 'void',
     },
     dispute: {
-      order: 14,
       tableName: 'disputes',
       dependencies: ['charge'],
       listFn: (p) => stripe.disputes.list(p),
@@ -177,7 +164,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
         dispute.status === 'won' || dispute.status === 'lost',
     },
     early_fraud_warning: {
-      order: 15,
       tableName: 'early_fraud_warnings',
       dependencies: ['payment_intent', 'charge'],
       listFn: (p) => stripe.radar.earlyFraudWarnings.list(p),
@@ -186,7 +172,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: true,
     },
     refund: {
-      order: 16,
       tableName: 'refunds',
       dependencies: ['payment_intent', 'charge'],
       listFn: (p) => stripe.refunds.list(p),
@@ -195,7 +180,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: true,
     },
     checkout_sessions: {
-      order: 17,
       tableName: 'checkout_sessions',
       dependencies: ['customer', 'subscription', 'payment_intent', 'invoice'],
       listFn: (p) => stripe.checkout.sessions.list(p),
@@ -205,7 +189,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       listExpands: [{ lines: (id) => stripe.checkout.sessions.listLineItems(id, { limit: 100 }) }],
     },
     active_entitlements: {
-      order: 18,
       tableName: 'active_entitlements',
       dependencies: ['customer'],
       listFn: (p) =>
@@ -217,7 +200,6 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
       sync: false,
     },
     review: {
-      order: 19,
       tableName: 'reviews',
       dependencies: ['payment_intent', 'charge'],
       listFn: (p) => stripe.reviews.list(p),
@@ -227,7 +209,11 @@ export function buildResourceRegistry(stripe: Stripe): Record<StripeObject, Reso
     },
   }
 
-  return core
+  const orderMap = computeResourceOrder(core)
+
+  return Object.fromEntries(
+    Object.entries(core).map(([key, config]) => [key, { ...config, order: orderMap.get(key)! }])
+  ) as Record<StripeObject, ResourceConfig>
 }
 
 /**
diff --git a/packages/sync-engine/src/utils/computeResourceOrder.ts b/packages/sync-engine/src/utils/computeResourceOrder.ts
new file mode 100644
index 00000000..478c3c3e
--- /dev/null
+++ b/packages/sync-engine/src/utils/computeResourceOrder.ts
@@ -0,0 +1,49 @@
+/**
+ * Compute sync order via topological sort (Kahn's algorithm).
+ */
+export function computeResourceOrder(
+  resources: Record<string, { dependencies?: string[] }>
+): Map<string, number> {
+  const names = Object.keys(resources)
+  const inDegree = new Map<string, number>()
+  const dependents = new Map<string, string[]>()
+
+  for (const name of names) {
+    inDegree.set(name, 0)
+    dependents.set(name, [])
+  }
+
+  for (const name of names) {
+    for (const dep of resources[name].dependencies ?? []) {
+      if (dependents.has(dep)) {
+        inDegree.set(name, (inDegree.get(name) ?? 0) + 1)
+        dependents.get(dep)!.push(name)
+      }
+    }
+  }
+
+  const queue: string[] = names.filter((n) => inDegree.get(n) === 0)
+  const orderMap = new Map<string, number>()
+  let order = 1
+
+  let front = 0
+  while (front < queue.length) {
+    const current = queue[front++]
+    orderMap.set(current, order++)
+
+    for (const dependent of dependents.get(current) ?? []) {
+      const newDeg = (inDegree.get(dependent) ?? 1) - 1
+      inDegree.set(dependent, newDeg)
+      if (newDeg === 0) {
+        queue.push(dependent)
+      }
+    }
+  }
+
+  if (orderMap.size !== names.length) {
+    const missing = names.filter((n) => !orderMap.has(n))
+    throw new Error(`Circular dependency detected among: ${missing.join(', ')}`)
+  }
+
+  return orderMap
+}

From 7e5b892d752b19e839204b340372e704987f217d Mon Sep 17 00:00:00 2001
From: Yostra <straya.mark@gmail.com>
Date: Mon, 2 Mar 2026 18:00:26 +0100
Subject: [PATCH 2/3] add tests

---
 .../src/utils/computeResourceOrder.test.ts    | 96 +++++++++++++++++++
 1 file changed, 96 insertions(+)
 create mode 100644 packages/sync-engine/src/utils/computeResourceOrder.test.ts

diff --git a/packages/sync-engine/src/utils/computeResourceOrder.test.ts b/packages/sync-engine/src/utils/computeResourceOrder.test.ts
new file mode 100644
index 00000000..8beebae3
--- /dev/null
+++ b/packages/sync-engine/src/utils/computeResourceOrder.test.ts
@@ -0,0 +1,96 @@
+import { describe, it, expect } from 'vitest'
+import { computeResourceOrder } from './computeResourceOrder'
+
+describe('computeResourceOrder', () => {
+  it('returns empty map for empty input', () => {
+    const result = computeResourceOrder({})
+    expect(result.size).toBe(0)
+  })
+
+  it('places dependencies before their dependents', () => {
+    const result = computeResourceOrder({
+      price: { dependencies: ['product'] },
+      product: {},
+    })
+    expect(result.get('product')).toBeLessThan(result.get('price')!)
+  })
+
+  it('handles a linear dependency chain', () => {
+    const result = computeResourceOrder({
+      subscription: { dependencies: ['price'] },
+      price: { dependencies: ['product'] },
+      product: {},
+    })
+    expect(result.get('product')).toBe(1)
+    expect(result.get('price')).toBe(2)
+    expect(result.get('subscription')).toBe(3)
+  })
+
+  it('handles diamond-shaped dependencies', () => {
+    const result = computeResourceOrder({
+      product: {},
+      price: { dependencies: ['product'] },
+      coupon: { dependencies: ['product'] },
+      subscription: { dependencies: ['price', 'coupon'] },
+    })
+    expect(result.get('product')).toBe(1)
+    expect(result.get('price')).toBeLessThan(result.get('subscription')!)
+    expect(result.get('coupon')).toBeLessThan(result.get('subscription')!)
+  })
+
+  it('ignores dependencies on unknown resources', () => {
+    const result = computeResourceOrder({
+      price: { dependencies: ['nonexistent'] },
+      product: {},
+    })
+    expect(result.size).toBe(2)
+    expect(result.has('price')).toBe(true)
+    expect(result.has('product')).toBe(true)
+  })
+
+  it('handles resources with empty dependency arrays', () => {
+    const result = computeResourceOrder({
+      product: { dependencies: [] },
+      customer: { dependencies: [] },
+    })
+    expect(result.size).toBe(2)
+  })
+
+  it('throws on circular dependency between two resources', () => {
+    expect(() =>
+      computeResourceOrder({
+        a: { dependencies: ['b'] },
+        b: { dependencies: ['a'] },
+      })
+    ).toThrow('Circular dependency detected among: a, b')
+  })
+
+  it('throws on circular dependency in a cycle of three', () => {
+    expect(() =>
+      computeResourceOrder({
+        a: { dependencies: ['c'] },
+        b: { dependencies: ['a'] },
+        c: { dependencies: ['b'] },
+      })
+    ).toThrow('Circular dependency detected among: a, b, c')
+  })
+
+  it('throws on self-referencing dependency', () => {
+    expect(() =>
+      computeResourceOrder({
+        a: { dependencies: ['a'] },
+      })
+    ).toThrow('Circular dependency detected among: a')
+  })
+
+  it('handles multiple independent dependency chains', () => {
+    const result = computeResourceOrder({
+      product: {},
+      price: { dependencies: ['product'] },
+      customer: {},
+      subscription: { dependencies: ['customer'] },
+    })
+    expect(result.get('product')).toBeLessThan(result.get('price')!)
+    expect(result.get('customer')).toBeLessThan(result.get('subscription')!)
+  })
+})

From 9c9a1b17dcc6bbb1f5cd23907f1529057241c082 Mon Sep 17 00:00:00 2001
From: Yostra <straya.mark@gmail.com>
Date: Mon, 2 Mar 2026 18:03:19 +0100
Subject: [PATCH 3/3] move to correct folder

---
 .../src/{utils => tests/unit}/computeResourceOrder.test.ts      | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
 rename packages/sync-engine/src/{utils => tests/unit}/computeResourceOrder.test.ts (97%)

diff --git a/packages/sync-engine/src/utils/computeResourceOrder.test.ts b/packages/sync-engine/src/tests/unit/computeResourceOrder.test.ts
similarity index 97%
rename from packages/sync-engine/src/utils/computeResourceOrder.test.ts
rename to packages/sync-engine/src/tests/unit/computeResourceOrder.test.ts
index 8beebae3..cf4a8249 100644
--- a/packages/sync-engine/src/utils/computeResourceOrder.test.ts
+++ b/packages/sync-engine/src/tests/unit/computeResourceOrder.test.ts
@@ -1,5 +1,5 @@
 import { describe, it, expect } from 'vitest'
-import { computeResourceOrder } from './computeResourceOrder'
+import { computeResourceOrder } from '../../utils/computeResourceOrder'
 
 describe('computeResourceOrder', () => {
   it('returns empty map for empty input', () => {