diff --git a/src/runner.ts b/src/runner.ts
index 28bc4e6..aab2998 100644
--- a/src/runner.ts
+++ b/src/runner.ts
@@ -1,5 +1,5 @@
 import type { ZodError } from 'zod'
-import type { FailureContext, Failure, Gate, Result, Step } from './types.js'
+import type { Failure, FailureContext, Gate, Result, Step } from './types.js'
 
 /**
  * Format a ZodError into a human-readable reason string.
@@ -17,7 +17,10 @@ function formatZodError(error: ZodError): string {
  * Run quality gates against a step's output.
  * Returns the first failure, or null if all gates pass.
  */
-function runGates(gates: Gate<unknown>[], output: unknown): { reason: string; context?: unknown } | null {
+function runGates(
+  gates: Gate<unknown>[],
+  output: unknown,
+): { reason: string; context?: unknown } | null {
   for (const gate of gates) {
     const result = gate(output)
     if (!result.ok) {
diff --git a/src/types.ts b/src/types.ts
index 7a38da4..eb60b1c 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -4,9 +4,7 @@ import type { z } from 'zod'
  * Result of a quality gate check.
  * Gates are pure synchronous functions — no LLM calls, no async.
  */
-export type GateResult =
-  | { ok: true }
-  | { ok: false; reason: string; context?: unknown }
+export type GateResult = { ok: true } | { ok: false; reason: string; context?: unknown }
 
 /**
  * A quality gate function. Receives a step's validated output
@@ -83,9 +81,7 @@ export interface Failure {
 /**
  * Pipeline result type. Success or structured failure.
  */
-export type Result<T> =
-  | { ok: true; value: T }
-  | { ok: false; failure: Failure }
+export type Result<T> = { ok: true; value: T } | { ok: false; failure: Failure }
 
 /**
  * Metadata returned by pipeline.describe().
diff --git a/tests/failure.test.ts b/tests/failure.test.ts
index f035049..f04f20c 100644
--- a/tests/failure.test.ts
+++ b/tests/failure.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 import { z } from 'zod'
-import { defineStep, pipeline, PipelineError } from '../src/index.js'
+import { PipelineError, defineStep, pipeline } from '../src/index.js'
 
 describe('structured failures', () => {
   it('schema_input failure has correct shape', async () => {
diff --git a/tests/gates.test.ts b/tests/gates.test.ts
index 134d42a..75d600c 100644
--- a/tests/gates.test.ts
+++ b/tests/gates.test.ts
@@ -45,9 +45,7 @@ describe('quality gates', () => {
       gates: [
         (out) => (out.text.length > 0 ? { ok: true } : { ok: false, reason: 'empty' }),
         (out) =>
-          out.text.length < 10
-            ? { ok: true }
-            : { ok: false, reason: 'too long (max 10 chars)' },
+          out.text.length < 10 ? { ok: true } : { ok: false, reason: 'too long (max 10 chars)' },
         (_out) => ({ ok: false, reason: 'this gate should not run' }),
       ],
       run: async (input) => ({ text: input.text.repeat(5) }),
diff --git a/tests/pipeline.test.ts b/tests/pipeline.test.ts
index b10ec66..9bb8b64 100644
--- a/tests/pipeline.test.ts
+++ b/tests/pipeline.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 import { z } from 'zod'
-import { defineStep, pipeline, PipelineError } from '../src/index.js'
+import { PipelineError, defineStep, pipeline } from '../src/index.js'
 
 const double = defineStep({
   name: 'double',
@@ -9,7 +9,7 @@ const double = defineStep({
   run: async (input) => ({ value: input.value * 2 }),
 })
 
-const toString = defineStep({
+const toText = defineStep({
   name: 'to-string',
   input: z.object({ value: z.number() }),
   output: z.object({ text: z.string() }),
@@ -28,7 +28,7 @@ describe('pipeline', () => {
   })
 
   it('chains multiple steps', async () => {
-    const p = pipeline('multi').step(double).step(toString)
+    const p = pipeline('multi').step(double).step(toText)
     const result = await p.run({ value: 21 })
 
     expect(result.ok).toBe(true)
@@ -54,7 +54,7 @@ describe('pipeline', () => {
       name: 'bad-output',
       input: z.object({ x: z.number() }),
       output: z.object({ y: z.string() }),
-      run: async (input) => ({ y: input.x } as unknown as { y: string }),
+      run: async (input) => ({ y: input.x }) as unknown as { y: string },
     })
 
     const p = pipeline('bad-output').step(badStep)
@@ -117,15 +117,15 @@ describe('pipeline', () => {
   })
 
   it('describe() returns pipeline metadata', () => {
-    const p = pipeline('described').step(double).step(toString)
+    const p = pipeline('described').step(double).step(toText)
     const desc = p.describe()
 
     expect(desc.name).toBe('described')
     expect(desc.steps).toHaveLength(2)
-    expect(desc.steps[0]!.name).toBe('double')
-    expect(desc.steps[1]!.name).toBe('to-string')
-    expect(desc.steps[0]!.inputSchema).toHaveProperty('type', 'object')
-    expect(desc.steps[0]!.outputSchema).toHaveProperty('type', 'object')
-    expect(desc.steps[0]!.gates).toBe(0)
+    expect(desc.steps[0]?.name).toBe('double')
+    expect(desc.steps[1]?.name).toBe('to-string')
+    expect(desc.steps[0]?.inputSchema).toHaveProperty('type', 'object')
+    expect(desc.steps[0]?.outputSchema).toHaveProperty('type', 'object')
+    expect(desc.steps[0]?.gates).toBe(0)
   })
 })
diff --git a/tests/retry.test.ts b/tests/retry.test.ts
index b18ef3d..ddacd27 100644
--- a/tests/retry.test.ts
+++ b/tests/retry.test.ts
@@ -63,9 +63,9 @@ describe('retry with failure context', () => {
     expect(contexts).toHaveLength(2)
     expect(contexts[0]).toBeUndefined() // first attempt
     expect(contexts[1]).toBeDefined() // second attempt has context
-    expect(contexts[1]!.type).toBe('gate')
-    expect(contexts[1]!.attempt).toBe(1)
-    expect(contexts[1]!.reason).toContain('title too long')
+    expect(contexts[1]?.type).toBe('gate')
+    expect(contexts[1]?.attempt).toBe(1)
+    expect(contexts[1]?.reason).toContain('title too long')
   })
 
   it('exhausts retries and returns structured failure', async () => {