diff --git a/bun.lock b/bun.lock
index 99b9dad3c7..916bc86fb3 100644
--- a/bun.lock
+++ b/bun.lock
@@ -459,13 +459,14 @@
     "packages/workflow-types": {
       "name": "@sim/workflow-types",
       "version": "0.1.0",
-      "dependencies": {
-        "reactflow": "^11.11.4",
-      },
       "devDependencies": {
         "@sim/tsconfig": "workspace:*",
+        "reactflow": "^11.11.4",
         "typescript": "^5.7.3",
       },
+      "peerDependencies": {
+        "reactflow": "^11.11.4",
+      },
     },
   },
   "trustedDependencies": [
diff --git a/packages/security/src/compare.test.ts b/packages/security/src/compare.test.ts
new file mode 100644
index 0000000000..265235e65b
--- /dev/null
+++ b/packages/security/src/compare.test.ts
@@ -0,0 +1,40 @@
+import { describe, expect, it } from 'vitest'
+import { safeCompare } from './compare'
+
+describe('safeCompare', () => {
+  it('returns true for identical strings', () => {
+    expect(safeCompare('abc', 'abc')).toBe(true)
+  })
+
+  it('returns false for equal-length different strings', () => {
+    expect(safeCompare('abc', 'abd')).toBe(false)
+  })
+
+  it('returns false for different-length strings without throwing', () => {
+    expect(safeCompare('short', 'longer-value')).toBe(false)
+    expect(safeCompare('', 'a')).toBe(false)
+    expect(safeCompare('a', '')).toBe(false)
+  })
+
+  it('returns true for two empty strings', () => {
+    expect(safeCompare('', '')).toBe(true)
+  })
+
+  it('handles long inputs', () => {
+    const a = 'x'.repeat(10_000)
+    const b = 'x'.repeat(10_000)
+    expect(safeCompare(a, b)).toBe(true)
+    expect(safeCompare(a, `${b.slice(0, -1)}y`)).toBe(false)
+  })
+
+  it('is case-sensitive', () => {
+    expect(safeCompare('ABC', 'abc')).toBe(false)
+  })
+
+  it('distinguishes hex digests that differ in one nibble', () => {
+    const a = 'b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff7'
+    const b = 'b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff8'
+    expect(safeCompare(a, b)).toBe(false)
+    expect(safeCompare(a, a)).toBe(true)
+  })
+})
diff --git a/packages/security/src/hmac.test.ts b/packages/security/src/hmac.test.ts
index f0f84d29f8..8daecafa0d 100644
--- a/packages/security/src/hmac.test.ts
+++ b/packages/security/src/hmac.test.ts
@@ -24,6 +24,11 @@ describe('hmacSha256Hex', () => {
   it('differs when secret changes', () => {
     expect(hmacSha256Hex('body', 'k1')).not.toBe(hmacSha256Hex('body', 'k2'))
   })
+
+  it('accepts a Buffer secret and matches the equivalent binary-string secret', () => {
+    const raw = Buffer.from('0b'.repeat(20), 'hex')
+    expect(hmacSha256Hex('Hi There', raw)).toBe(hmacSha256Hex('Hi There', raw.toString('binary')))
+  })
 })
 
 describe('hmacSha256Base64', () => {
@@ -40,4 +45,11 @@ describe('hmacSha256Base64', () => {
     const b64 = hmacSha256Base64('body', 'secret')
     expect(Buffer.from(b64, 'base64').toString('hex')).toBe(hex)
   })
+
+  it('accepts a Buffer secret (Svix / MS-Teams scheme)', () => {
+    const secret = Buffer.from('whsec-decoded-bytes')
+    const hex = hmacSha256Hex('body', secret)
+    const b64 = hmacSha256Base64('body', secret)
+    expect(Buffer.from(b64, 'base64').toString('hex')).toBe(hex)
+  })
 })
diff --git a/packages/workflow-persistence/package.json b/packages/workflow-persistence/package.json
index 88b1be60d4..00a99f1dff 100644
--- a/packages/workflow-persistence/package.json
+++ b/packages/workflow-persistence/package.json
@@ -10,6 +10,10 @@
     "node": ">=20.0.0"
   },
   "exports": {
+    ".": {
+      "types": "./src/index.ts",
+      "default": "./src/index.ts"
+    },
     "./load": {
       "types": "./src/load.ts",
       "default": "./src/load.ts"
diff --git a/packages/workflow-persistence/src/index.ts b/packages/workflow-persistence/src/index.ts
new file mode 100644
index 0000000000..ad0b35248c
--- /dev/null
+++ b/packages/workflow-persistence/src/index.ts
@@ -0,0 +1,19 @@
+export {
+  loadWorkflowFromNormalizedTablesRaw,
+  persistMigratedBlocks,
+  type RawNormalizedWorkflow,
+} from './load'
+export { saveWorkflowToNormalizedTables } from './save'
+export {
+  DEFAULT_SUBBLOCK_TYPE,
+  mergeSubBlockValues,
+  mergeSubblockStateWithValues,
+} from './subblocks'
+export {
+  convertLoopBlockToLoop,
+  convertParallelBlockToParallel,
+  findChildNodes,
+  generateLoopBlocks,
+  generateParallelBlocks,
+} from './subflow-helpers'
+export type { DbOrTx, NormalizedWorkflowData } from './types'
diff --git a/packages/workflow-persistence/src/load.ts b/packages/workflow-persistence/src/load.ts
index 7142f9ae7c..8f19375c81 100644
--- a/packages/workflow-persistence/src/load.ts
+++ b/packages/workflow-persistence/src/load.ts
@@ -18,6 +18,13 @@ export interface RawNormalizedWorkflow extends NormalizedWorkflowData {
  * backfill, tool sanitization) depend on the block/tool registry that lives in
  * the Next app and should not be pulled into leaf services. Callers that want
  * migrated state should wrap this with their own migration pipeline.
+ *
+ * Invariant: downstream migrations must not mutate `block.data.collection`,
+ * `block.data.whileCondition`, or `block.data.doWhileCondition`. Those fields
+ * are patched here from the subflow config on the pre-migration block, and
+ * callers re-sync only `loop.enabled`/`parallel.enabled` from the migrated
+ * block. If a future migration rewrites these data fields, the loop/parallel
+ * config on the returned object will silently diverge from the migrated block.
  */
 export async function loadWorkflowFromNormalizedTablesRaw(
   workflowId: string
diff --git a/packages/workflow-types/package.json b/packages/workflow-types/package.json
index dd8f6832c2..cc041b0caa 100644
--- a/packages/workflow-types/package.json
+++ b/packages/workflow-types/package.json
@@ -26,11 +26,12 @@
     "format": "biome format --write .",
     "format:check": "biome format ."
   },
-  "dependencies": {
+  "peerDependencies": {
     "reactflow": "^11.11.4"
   },
   "devDependencies": {
     "@sim/tsconfig": "workspace:*",
+    "reactflow": "^11.11.4",
     "typescript": "^5.7.3"
   }
 }