diff --git a/.changeset/remove-ci-trace-auto-enable.md b/.changeset/remove-ci-trace-auto-enable.md
new file mode 100644
index 0000000..260f301
--- /dev/null
+++ b/.changeset/remove-ci-trace-auto-enable.md
@@ -0,0 +1,15 @@
+---
+'command-stream': patch
+---
+
+Fix trace logs interfering with output when CI=true
+
+- Removed automatic trace log enabling when CI environment variable is set
+- Trace logs no longer pollute stderr in CI/CD environments (GitHub Actions, GitLab CI, etc.)
+- Added COMMAND_STREAM_TRACE environment variable for explicit trace control
+- COMMAND_STREAM_TRACE=true explicitly enables tracing
+- COMMAND_STREAM_TRACE=false explicitly disables tracing (overrides COMMAND_STREAM_VERBOSE)
+- COMMAND_STREAM_VERBOSE=true continues to work as before
+- JSON parsing works reliably in CI environments
+
+Fixes #135
diff --git a/examples/reproduce-issue-135-v2.mjs b/examples/reproduce-issue-135-v2.mjs
new file mode 100755
index 0000000..da619ca
--- /dev/null
+++ b/examples/reproduce-issue-135-v2.mjs
@@ -0,0 +1,15 @@
+#!/usr/bin/env node
+// Reproducing issue #135: Trace logs interfere with output when CI=true
+// This test sets CI=true BEFORE importing the module
+
+process.env.CI = 'true';
+
+import { $ } from '../src/$.mjs';
+
+console.log('=== Test with CI=true set BEFORE import ===');
+const $silent = $({ mirror: false, capture: true });
+const result = await $silent`echo '{"status":"ok"}'`;
+console.log('Output:', result.stdout || result);
+console.log(
+  '\n=== Expected: Should be just {"status":"ok"} without trace logs ==='
+);
diff --git a/examples/reproduce-issue-135.mjs b/examples/reproduce-issue-135.mjs
new file mode 100755
index 0000000..10bc1e5
--- /dev/null
+++ b/examples/reproduce-issue-135.mjs
@@ -0,0 +1,17 @@
+#!/usr/bin/env node
+// Reproducing issue #135: Trace logs interfere with output when CI=true
+
+import { $ } from '../src/$.mjs';
+
+const $silent = $({ mirror: false, capture: true });
+
+console.log('=== Test 1: Without CI environment ===');
+const result1 = await $silent`echo '{"status":"ok"}'`;
+console.log('Output:', result1.stdout || result1);
+
+console.log('\n=== Test 2: With CI=true environment ===');
+process.env.CI = 'true';
+const result2 = await $silent`echo '{"status":"ok"}'`;
+console.log('Output:', result2.stdout || result2);
+
+console.log('\n=== Expected: Both outputs should be just {"status":"ok"} ===');
diff --git a/examples/test-issue-135-comprehensive.mjs b/examples/test-issue-135-comprehensive.mjs
new file mode 100755
index 0000000..3f8d574
--- /dev/null
+++ b/examples/test-issue-135-comprehensive.mjs
@@ -0,0 +1,41 @@
+#!/usr/bin/env node
+// Comprehensive test for issue #135: Trace logs interfere with output
+
+import { $ } from '../src/$.mjs';
+
+console.log(
+  '=== Test 1: Default (no env vars, mirror:false, capture:true) ==='
+);
+const $silent = $({ mirror: false, capture: true });
+const result1 = await $silent`echo test1`;
+console.log('Output:', result1.stdout);
+console.log('Expected: just "test1"\n');
+
+console.log('=== Test 2: CI=true (should NOT produce trace logs) ===');
+process.env.CI = 'true';
+const $silent2 = $({ mirror: false, capture: true });
+const result2 = await $silent2`echo test2`;
+console.log('Output:', result2.stdout);
+console.log('Expected: just "test2"\n');
+
+console.log(
+  '=== Test 3: CI=true + COMMAND_STREAM_TRACE=true (should produce trace logs) ==='
+);
+process.env.COMMAND_STREAM_TRACE = 'true';
+const $silent3 = $({ mirror: false, capture: true });
+const result3 = await $silent3`echo test3`;
+console.log('Output:', result3.stdout);
+console.log('Expected: "test3" (trace logs should appear in stderr above)\n');
+
+console.log(
+  '=== Test 4: COMMAND_STREAM_TRACE=false overrides COMMAND_STREAM_VERBOSE=true ==='
+);
+process.env.COMMAND_STREAM_VERBOSE = 'true';
+process.env.COMMAND_STREAM_TRACE = 'false';
+const result4 = await $silent`echo test4`;
+console.log('Output:', result4.stdout);
+console.log(
+  'Expected: just "test4" (no trace logs even though VERBOSE=true)\n'
+);
+
+console.log('=== All tests completed ===');
diff --git a/examples/test-trace-option.mjs b/examples/test-trace-option.mjs
new file mode 100755
index 0000000..e66aa50
--- /dev/null
+++ b/examples/test-trace-option.mjs
@@ -0,0 +1,21 @@
+#!/usr/bin/env node
+// Test the trace option in $ config
+
+import { $ } from '../src/$.mjs';
+
+console.log('=== Test: mirror:false with trace:false in CI environment ===');
+process.env.CI = 'true';
+
+const $silent = $({ mirror: false, capture: true, trace: false });
+const result = await $silent`echo '{"status":"ok"}'`;
+console.log('JSON Output:', result.stdout);
+
+console.log('\n=== Parsing JSON to verify it works ===');
+try {
+  const parsed = JSON.parse(result.stdout);
+  console.log('Parsed successfully:', parsed);
+  console.log('✓ Test PASSED: No trace logs interfered with JSON parsing');
+} catch (e) {
+  console.error('✗ Test FAILED: Could not parse JSON:', e.message);
+  console.error('Raw output:', result.stdout);
+}
diff --git a/src/$.mjs b/src/$.mjs
index 05040a1..445264d 100755
--- a/src/$.mjs
+++ b/src/$.mjs
@@ -12,14 +12,30 @@ import { parseShellCommand, needsRealShell } from './shell-parser.mjs';
 
 const isBun = typeof globalThis.Bun !== 'undefined';
 
-const VERBOSE =
-  process.env.COMMAND_STREAM_VERBOSE === 'true' || process.env.CI === 'true';
-
 // Trace function for verbose logging
-function trace(category, messageOrFunc) {
+// Can be controlled via COMMAND_STREAM_VERBOSE or COMMAND_STREAM_TRACE env vars
+// Can be disabled per-command via trace: false option
+// CI environment no longer auto-enables tracing
+function trace(category, messageOrFunc, runner = null) {
+  // Check if runner explicitly disabled tracing
+  if (runner && runner.options && runner.options.trace === false) {
+    return;
+  }
+
+  // Check global trace setting (evaluated dynamically for runtime changes)
+  const TRACE_ENV = process.env.COMMAND_STREAM_TRACE;
+  const VERBOSE_ENV = process.env.COMMAND_STREAM_VERBOSE === 'true';
+
+  // COMMAND_STREAM_TRACE=false explicitly disables tracing even if COMMAND_STREAM_VERBOSE=true
+  // COMMAND_STREAM_TRACE=true explicitly enables tracing
+  // Otherwise, use COMMAND_STREAM_VERBOSE
+  const VERBOSE =
+    TRACE_ENV === 'false' ? false : TRACE_ENV === 'true' ? true : VERBOSE_ENV;
+
   if (!VERBOSE) {
     return;
   }
+
   const message =
     typeof messageOrFunc === 'function' ? messageOrFunc() : messageOrFunc;
   const timestamp = new Date().toISOString();
diff --git a/src/$.utils.mjs b/src/$.utils.mjs
index d36082e..1dd1a7b 100644
--- a/src/$.utils.mjs
+++ b/src/$.utils.mjs
@@ -1,11 +1,23 @@
 import path from 'path';
 
-const VERBOSE = process.env.COMMAND_STREAM_VERBOSE === 'true';
-
+// Trace function for verbose logging - consistent with src/$.mjs
+// Can be controlled via COMMAND_STREAM_VERBOSE or COMMAND_STREAM_TRACE env vars
+// CI environment no longer auto-enables tracing
 export function trace(category, messageOrFunc) {
+  // Check global trace setting (evaluated dynamically for runtime changes)
+  const TRACE_ENV = process.env.COMMAND_STREAM_TRACE;
+  const VERBOSE_ENV = process.env.COMMAND_STREAM_VERBOSE === 'true';
+
+  // COMMAND_STREAM_TRACE=false explicitly disables tracing even if COMMAND_STREAM_VERBOSE=true
+  // COMMAND_STREAM_TRACE=true explicitly enables tracing
+  // Otherwise, use COMMAND_STREAM_VERBOSE
+  const VERBOSE =
+    TRACE_ENV === 'false' ? false : TRACE_ENV === 'true' ? true : VERBOSE_ENV;
+
   if (!VERBOSE) {
     return;
   }
+
   const message =
     typeof messageOrFunc === 'function' ? messageOrFunc() : messageOrFunc;
   const timestamp = new Date().toISOString();
diff --git a/tests/issue-135-final.test.mjs b/tests/issue-135-final.test.mjs
new file mode 100755
index 0000000..f7edc02
--- /dev/null
+++ b/tests/issue-135-final.test.mjs
@@ -0,0 +1,58 @@
+// Final test for issue #135: CI environment should not auto-enable trace
+// This test verifies the main fix: CI=true should NOT cause trace logs
+import { describe, it, beforeEach } from 'bun:test';
+import assert from 'assert';
+import { $ } from '../src/$.mjs';
+
+describe('Issue #135: CI environment no longer auto-enables trace logs', () => {
+  beforeEach(() => {
+    // Clean up environment before each test
+    delete process.env.COMMAND_STREAM_VERBOSE;
+    delete process.env.COMMAND_STREAM_TRACE;
+    delete process.env.CI;
+  });
+
+  it('should NOT emit trace logs when CI=true (main fix)', async () => {
+    process.env.CI = 'true';
+
+    const $silent = $({ mirror: false, capture: true });
+    const result = await $silent`echo '{"status":"ok"}'`;
+
+    // Output should be clean JSON without trace logs
+    assert.strictEqual(result.stdout.trim(), '{"status":"ok"}');
+
+    // Should be parseable as JSON
+    const parsed = JSON.parse(result.stdout);
+    assert.deepStrictEqual(parsed, { status: 'ok' });
+  });
+
+  it('should allow JSON parsing in CI environment', async () => {
+    process.env.CI = 'true';
+
+    const $silent = $({ mirror: false, capture: true });
+    const result = await $silent`echo '{"count":42,"items":["a","b","c"]}'`;
+
+    // Should be able to parse complex JSON
+    const parsed = JSON.parse(result.stdout);
+    assert.strictEqual(parsed.count, 42);
+    assert.deepStrictEqual(parsed.items, ['a', 'b', 'c']);
+  });
+
+  it('should NOT produce trace logs by default (no env vars)', async () => {
+    const $silent = $({ mirror: false, capture: true });
+    const result = await $silent`echo test`;
+
+    // Simple text output should be clean
+    assert.strictEqual(result.stdout.trim(), 'test');
+  });
+
+  it('should work with mirror:false in CI environment', async () => {
+    process.env.CI = 'true';
+
+    const $silent = $({ mirror: false, capture: true });
+    const result = await $silent`echo hello`;
+
+    assert.strictEqual(result.stdout.trim(), 'hello');
+    assert.strictEqual(result.code, 0);
+  });
+});