diff --git a/gitops/reuse.ymal b/gitops/reuse.ymal
index 9400b54f..02c0fd1e 100644
--- a/gitops/reuse.ymal
+++ b/gitops/reuse.ymal
@@ -5,6 +5,15 @@ metadata:
   ownerRepository: pikasTech/HWLAB
 spec:
   envArtifactGroups:
+    hwlab-go-runtime-env:
+      enabled: true
+      mode: env-reuse-git-mirror-checkout
+      buildService: hwlab-user-billing
+      imageRepository: hwlab-go-runtime-env
+      cacheRepository: cache/hwlab-go-runtime-env
+      services:
+        - hwlab-user-billing
+        - hwlab-workbench-runtime
     hwlab-ts-runtime-env:
       enabled: true
       mode: env-reuse-git-mirror-checkout
diff --git a/scripts/ci-plan.test.mjs b/scripts/ci-plan.test.mjs
index 3fa1e733..e1e35fce 100644
--- a/scripts/ci-plan.test.mjs
+++ b/scripts/ci-plan.test.mjs
@@ -1145,6 +1145,79 @@ test("v03 planner reads env reuse declarations and catalog from v03 lane config"
   }
 });
 
+test("v03 planner builds one shared Go env artifact for compatible Go services", async () => {
+  const repo = await createFixtureRepo({ catalog: false });
+  await addGoEnvReuseFixture(repo);
+  await writeFile(path.join(repo, "go.mod"), "module github.com/pikasTech/HWLAB\n\ngo 1.22\n\nrequire example.com/direct v0.0.2\n");
+  await git(repo, ["add", "go.mod"]);
+  await git(repo, ["commit", "-m", "change go env dependency"]);
+
+  const plan = await createCiPlan({
+    repoRoot: repo,
+    lane: "v03",
+    baseRef: "HEAD~1",
+    targetRef: "HEAD",
+    artifactCatalogPath: "deploy/nonexistent-artifact-catalog.json",
+    services: ["hwlab-user-billing", "hwlab-workbench-runtime"]
+  });
+
+  const group = plan.envArtifactGroups.find((item) => item.id === "hwlab-go-runtime-env");
+  assert.equal(group.buildRequired, true);
+  assert.deepEqual(group.buildServices, ["hwlab-user-billing"]);
+  assert.deepEqual(group.consumerServices, ["hwlab-workbench-runtime"]);
+  assert.deepEqual(plan.buildServices, ["hwlab-user-billing"]);
+  const userBilling = plan.services.find((service) => service.serviceId === "hwlab-user-billing");
+  const workbenchRuntime = plan.services.find((service) => service.serviceId === "hwlab-workbench-runtime");
+  assert.equal(userBilling.envArtifactCacheRef, "127.0.0.1:5000/hwlab/cache/hwlab-go-runtime-env");
+  assert.equal(workbenchRuntime.envArtifactCacheRef, "127.0.0.1:5000/hwlab/cache/hwlab-go-runtime-env");
+  assert.equal(userBilling.environmentImage, `127.0.0.1:5000/hwlab/hwlab-go-runtime-env:env-${userBilling.environmentInputHash.slice(0, 12)}`);
+  assert.equal(workbenchRuntime.environmentImage, userBilling.environmentImage);
+  assert.equal(workbenchRuntime.sharedEnvBuildSkipped, true);
+  assert.equal(workbenchRuntime.buildRequired, false);
+});
+
+test("v03 planner ignores Go launcher comment-only changes for env identity", async () => {
+  const repo = await createFixtureRepo({ catalog: false });
+  await addGoEnvReuseFixture(repo);
+  const initialSha = (await git(repo, ["rev-parse", "HEAD"])).stdout.trim();
+  const initialPlan = await createCiPlan({
+    repoRoot: repo,
+    lane: "v03",
+    baseRef: "HEAD",
+    targetRef: initialSha,
+    artifactCatalogPath: "deploy/nonexistent-artifact-catalog.json",
+    services: ["hwlab-user-billing", "hwlab-workbench-runtime"]
+  });
+  await writeFile(path.join(repo, "deploy/artifact-catalog.v03.json"), JSON.stringify(createCatalogFixture("ready", catalogOptionsFromPlan(initialPlan, {
+    sourceCommitId: initialSha,
+    serviceIds: ["hwlab-user-billing", "hwlab-workbench-runtime"]
+  })), null, 2));
+  await git(repo, ["add", "deploy/artifact-catalog.v03.json"]);
+  await git(repo, ["commit", "-m", "seed go env reuse catalog"]);
+
+  await writeFile(path.join(repo, "deploy/runtime/launcher/hwlab-go-env-reuse-launcher.mjs"), "// changed explanatory comment\nexport const goEnvLauncher = true;\n");
+  await git(repo, ["add", "deploy/runtime/launcher/hwlab-go-env-reuse-launcher.mjs"]);
+  await git(repo, ["commit", "-m", "change go launcher comment only"]);
+
+  const plan = await createCiPlan({
+    repoRoot: repo,
+    lane: "v03",
+    baseRef: "HEAD~1",
+    targetRef: "HEAD",
+    artifactCatalogPath: "deploy/artifact-catalog.v03.json",
+    services: ["hwlab-user-billing", "hwlab-workbench-runtime"]
+  });
+
+  assert.deepEqual(plan.affectedServices, []);
+  assert.deepEqual(plan.buildServices, []);
+  assert.equal(plan.imageBuildRequired, false);
+  for (const service of plan.services) {
+    assert.equal(service.runtimeReuseDecision.envIdentityHit, true, service.serviceId);
+    assert.equal(service.environmentInputChanged, false, service.serviceId);
+    assert.equal(service.buildRequired, false, service.serviceId);
+  }
+});
+
 async function createFixtureRepo(options = {}) {
   const serviceIds = options.serviceIds ?? ["hwlab-cloud-api", "hwlab-cloud-web"];
   const laneServiceIds = options.laneServiceIds ?? V02_RUNTIME_SERVICE_IDS;
@@ -1255,6 +1328,84 @@ function planV02CoreServices(repo, options) {
   });
 }
 
+async function addGoEnvReuseFixture(repo) {
+  await mkdir(path.join(repo, "cmd/hwlab-user-billing"), { recursive: true });
+  await mkdir(path.join(repo, "cmd/hwlab-workbench-runtime"), { recursive: true });
+  await mkdir(path.join(repo, "internal/userbilling"), { recursive: true });
+  await mkdir(path.join(repo, "internal/workbenchruntime"), { recursive: true });
+  await mkdir(path.join(repo, "gitops"), { recursive: true });
+  await writeFile(path.join(repo, "go.mod"), "module github.com/pikasTech/HWLAB\n\ngo 1.22\n\nrequire example.com/direct v0.0.1\n");
+  await writeFile(path.join(repo, "go.sum"), "example.com/direct v0.0.1 h1:fixture\n");
+  await writeFile(path.join(repo, "cmd/hwlab-user-billing/main.go"), "package main\n\nfunc main() {}\n");
+  await writeFile(path.join(repo, "cmd/hwlab-workbench-runtime/main.go"), "package main\n\nfunc main() {}\n");
+  await writeFile(path.join(repo, "internal/userbilling/billing.go"), "package userbilling\n");
+  await writeFile(path.join(repo, "internal/workbenchruntime/runtime.go"), "package workbenchruntime\n");
+  await writeFile(path.join(repo, "deploy/runtime/boot/hwlab-user-billing.sh"), "#!/bin/sh\nexec /app/hwlab-user-billing\n");
+  await writeFile(path.join(repo, "deploy/runtime/boot/hwlab-workbench-runtime.sh"), "#!/bin/sh\nexec /app/hwlab-workbench-runtime\n");
+  await writeFile(path.join(repo, "deploy/runtime/launcher/hwlab-go-env-reuse-launcher.mjs"), "// initial explanatory comment\nexport const goEnvLauncher = true;\n");
+  const deployPath = path.join(repo, "deploy/deploy.yaml");
+  const deploy = await readStructuredFile(repo, deployPath);
+  deploy.lanes.v03.envReuseServices = uniquePreserveOrder([
+    ...deploy.lanes.v03.envReuseServices,
+    "hwlab-user-billing",
+    "hwlab-workbench-runtime"
+  ]);
+  deploy.lanes.v03.bootScripts["hwlab-user-billing"] = "deploy/runtime/boot/hwlab-user-billing.sh";
+  deploy.lanes.v03.bootScripts["hwlab-workbench-runtime"] = "deploy/runtime/boot/hwlab-workbench-runtime.sh";
+  deploy.lanes.v03.serviceDeclarations["hwlab-user-billing"] = {
+    runtimeKind: "go-service",
+    entrypoint: "cmd/hwlab-user-billing/main.go",
+    artifactKind: "go-service",
+    healthPath: "/health/live",
+    healthPort: 7101,
+    componentPaths: ["cmd/hwlab-user-billing/", "internal/userbilling/"],
+    env: {},
+    observable: true
+  };
+  deploy.lanes.v03.serviceDeclarations["hwlab-workbench-runtime"] = {
+    runtimeKind: "go-service",
+    entrypoint: "cmd/hwlab-workbench-runtime/main.go",
+    artifactKind: "go-service",
+    healthPath: "/health/live",
+    healthPort: 7102,
+    componentPaths: ["cmd/hwlab-workbench-runtime/", "internal/workbenchruntime/"],
+    env: {},
+    observable: true
+  };
+  await writeStructuredFile(repo, deployPath, deploy);
+  await writeStructuredFile(repo, "gitops/reuse.ymal", {
+    apiVersion: "unidesk.pikapython.com/v1alpha1",
+    kind: "RuntimeReuseConfig",
+    metadata: { name: "hwlab-v03-reuse", ownerRepository: "pikasTech/HWLAB" },
+    spec: {
+      envArtifactGroups: {
+        "hwlab-go-runtime-env": {
+          enabled: true,
+          mode: "env-reuse-git-mirror-checkout",
+          buildService: "hwlab-user-billing",
+          imageRepository: "hwlab-go-runtime-env",
+          cacheRepository: "cache/hwlab-go-runtime-env",
+          services: ["hwlab-user-billing", "hwlab-workbench-runtime"]
+        }
+      },
+      services: Object.fromEntries(["hwlab-user-billing", "hwlab-workbench-runtime"].map((serviceId) => [serviceId, {
+        runtimeReuse: {
+          enabled: true,
+          codeIdentity: { paths: [serviceId === "hwlab-user-billing" ? "cmd/hwlab-user-billing" : "cmd/hwlab-workbench-runtime"] },
+          envIdentity: { paths: ["go.mod", "go.sum", "deploy/runtime/launcher/hwlab-go-env-reuse-launcher.mjs"] }
+        },
+        envReuse: {
+          enabled: true,
+          mode: "env-reuse-git-mirror-checkout",
+          envIdentityFiles: ["go.mod", "go.sum", "deploy/runtime/launcher/hwlab-go-env-reuse-launcher.mjs"]
+        }
+      }]))
+    }
+  });
+  await git(repo, ["add", "."]);
+  await git(repo, ["commit", "-m", "add go env reuse fixture"]);
+}
+
 function createDeployFixture({ serviceIds = V02_RUNTIME_SERVICE_IDS } = {}) {
   const v02 = {
         sourceRepo: "git@github.com:pikasTech/HWLAB.git",
@@ -1380,6 +1531,11 @@ function createDeployFixture({ serviceIds = V02_RUNTIME_SERVICE_IDS } = {}) {
 
 function createCatalogFixture(mode, options = {}) {
   const digest = mode === "ready" ? `sha256:${"1".repeat(64)}` : "not_published";
+  const envReuseCatalogServiceIds = new Set([
+    ...V02_RUNTIME_SERVICE_IDS,
+    ...Object.keys(options.environmentInputHashes ?? {}),
+    ...Object.keys(options.codeInputHashes ?? {})
+  ]);
   const serviceIds = options.serviceIds ?? uniquePreserveOrder([
     "hwlab-cloud-api",
     "hwlab-cloud-web",
@@ -1398,7 +1554,7 @@ function createCatalogFixture(mode, options = {}) {
       ...((options.componentInputHashes?.[serviceId] || (serviceId === "hwlab-cloud-api" && options.cloudApiComponentInputHash)) ? {
         componentInputHash: options.cloudApiComponentInputHash ?? options.componentInputHashes?.[serviceId]
       } : {}),
-      ...(V02_RUNTIME_SERVICE_IDS.includes(serviceId) ? {
+      ...(envReuseCatalogServiceIds.has(serviceId) ? {
         runtimeMode: "env-reuse-git-mirror-checkout",
         envReuse: true,
         environmentImage: `127.0.0.1:5000/hwlab/${serviceId}-env:env-abc1234`,
diff --git a/scripts/src/ci-plan-lib.mjs b/scripts/src/ci-plan-lib.mjs
index b44aa07d..35819a8b 100644
--- a/scripts/src/ci-plan-lib.mjs
+++ b/scripts/src/ci-plan-lib.mjs
@@ -25,6 +25,10 @@ export const GO_RUNTIME_DEP_PATHS = Object.freeze([
   "deploy/runtime/launcher/hwlab-go-env-reuse-launcher.mjs"
 ]);
 
+const COMMENT_INSENSITIVE_ENV_IDENTITY_PATHS = new Set([
+  "deploy/runtime/launcher/hwlab-go-env-reuse-launcher.mjs"
+]);
+
 export const DEFAULT_RUNTIME_PACKAGE_FIELDS = Object.freeze([
   "dependencies",
   "optionalDependencies",
@@ -629,12 +633,25 @@ export async function runtimeDependencyChangedPaths(repoRoot, baseRef, targetRef
       result.add(filePath);
       continue;
     }
+    if (COMMENT_INSENSITIVE_ENV_IDENTITY_PATHS.has(filePath)) {
+      if (await envIdentityTextChanged(repoRoot, baseRef, targetRef, filePath)) result.add(filePath);
+      continue;
+    }
     if (filePath !== "package.json") continue;
     if (await packageRuntimeFieldsChanged(repoRoot, baseRef, targetRef, filePath)) result.add(filePath);
   }
   return result;
 }
 
+async function envIdentityTextChanged(repoRoot, baseRef, targetRef, filePath) {
+  const [before, after] = await Promise.all([
+    readTextFromGit(repoRoot, baseRef, filePath, null),
+    readTextFromGit(repoRoot, targetRef, filePath, null)
+  ]);
+  if (before === null || after === null) return true;
+  return stableJson(normalizeEnvIdentityText(filePath, before)) !== stableJson(normalizeEnvIdentityText(filePath, after));
+}
+
 async function serviceRuntimeConfigChanged(repoRoot, deployConfigPath, baseRef, targetRef, lane, serviceId) {
   const [before, after] = await Promise.all([
     readDeployConfigFromGit(repoRoot, baseRef, deployConfigPath),
@@ -690,13 +707,21 @@ function pickRuntimePackageJson(packageJson) {
 
 async function readJsonFromGit(repoRoot, ref, filePath, fallback) {
   try {
-    const value = await gitValue(repoRoot, ["show", `${ref}:${filePath}`]);
+    const value = await readTextFromGit(repoRoot, ref, filePath, "");
     return JSON.parse(value);
   } catch {
     return fallback;
   }
 }
 
+async function readTextFromGit(repoRoot, ref, filePath, fallback) {
+  try {
+    return await gitValue(repoRoot, ["show", `${ref}:${filePath}`]);
+  } catch {
+    return fallback;
+  }
+}
+
 export function enabledEnvReuseServices(deployJson, lane, serviceIds) {
   const configured = deployJson?.lanes?.[lane]?.envReuseServices;
   const values = Array.isArray(configured) ? configured : [];
@@ -925,6 +950,10 @@ export async function hashGitPaths(repoRoot, targetRef, paths, options = {}) {
         const packageJson = await readJsonFromGit(repoRoot, targetRef, filePath, null);
         return `100644 blob ${stableHash(pickRuntimePackageJson(packageJson))}\t${filePath}`;
       }
+      if (COMMENT_INSENSITIVE_ENV_IDENTITY_PATHS.has(filePath)) {
+        const source = await readTextFromGit(repoRoot, targetRef, filePath, "");
+        return `100644 blob ${stableHash(normalizeEnvIdentityText(filePath, source))}\t${filePath}`;
+      }
       return line;
     })))
     .filter(Boolean)
@@ -932,6 +961,19 @@ export async function hashGitPaths(repoRoot, targetRef, paths, options = {}) {
   return stableHash({ entries: lines });
 }
 
+function normalizeEnvIdentityText(filePath, source) {
+  const normalizedPath = normalizeRepoPath(filePath);
+  const text = String(source ?? "").replace(/\r\n?/gu, "\n");
+  if (!COMMENT_INSENSITIVE_ENV_IDENTITY_PATHS.has(normalizedPath)) return text;
+  return text
+    .split("\n")
+    .filter((line) => {
+      const trimmed = line.trim();
+      return trimmed && !trimmed.startsWith("//");
+    })
+    .join("\n");
+}
+
 async function hashEnvReuseInputs(repoRoot, targetRef, paths, recipe, options = {}) {
   return stableHash({
     gitPaths: await hashGitPaths(repoRoot, targetRef, paths, options),