diff --git a/packages/env/README.md b/packages/env/README.md
index e6f934996..fc8f27e0c 100644
--- a/packages/env/README.md
+++ b/packages/env/README.md
@@ -5,22 +5,86 @@ into a common interface for consumption by `@percy/client`.
 
 ## Supported Environments
 
+Auto-detected based on environment variables that the CI provider sets during a build.
+
 - [AppVeyor](https://www.browserstack.com/docs/percy/ci-cd/appveyor)
+- [Atlassian Bamboo](#supported-environments) (needs doc)
+- [AWS CodeBuild](#supported-environments) (needs doc)
 - [Azure Pipelines](https://www.browserstack.com/docs/percy/ci-cd/azure-pipelines)
 - [Bitbucket Pipelines](https://www.browserstack.com/docs/percy/ci-cd/bitbucket-pipeline)
+- [Bitrise](#supported-environments) (needs doc)
 - [Buildkite](https://www.browserstack.com/docs/percy/ci-cd/buildkite)
 - [CircleCI](https://www.browserstack.com/docs/percy/ci-cd/circleci)
+- [Cloudflare Pages](#supported-environments) (needs doc)
+- [Codemagic](#supported-environments) (needs doc)
 - [Codeship](https://www.browserstack.com/docs/percy/ci-cd/codeship)
 - [Drone CI](https://docs.percy.io/docs/drone)
 - [GitHub Actions](https://www.browserstack.com/docs/percy/ci-cd/github-actions)
 - [GitLab CI](https://www.browserstack.com/docs/percy/ci-cd/gitlab)
+- [GoCD](#supported-environments) (needs doc)
+- [Google Cloud Build](#supported-environments) (needs doc)
+- [Harness CI](#supported-environments) (needs doc)
 - [Heroku CI](#supported-environments) (needs doc)
 - [Jenkins](https://www.browserstack.com/docs/percy/ci-cd/jenkins)
 - [Jenkins PRB](https://www.browserstack.com/docs/percy/ci-cd/jenkins)
 - [Netlify](https://www.browserstack.com/docs/percy/ci-cd/netlify)
 - [Probo.CI](#supported-environments) (needs doc)
 - [Semaphore](https://www.browserstack.com/docs/percy/ci-cd/semaphore)
+- [TeamCity](#supported-environments) (needs doc)
 - [Travis CI](https://www.browserstack.com/docs/percy/ci-cd/travis-ci)
+- [Vercel](#vercel) — see note below
+- [Woodpecker CI](#supported-environments) (needs doc)
+
+## Opt-in Environments
+
+Kubernetes-native pipelines do not inject provider-identifying environment variables
+into step containers by default. To enable Percy detection on these systems, expose
+the following variables via template substitution in your pipeline definition.
+
+### Tekton Pipelines
+
+```yaml
+steps:
+  - name: percy
+    image: node:20
+    env:
+      - name: TEKTON_PIPELINE_RUN          # required — triggers detection
+        value: "$(context.pipelineRun.name)"
+      - name: TEKTON_COMMIT_SHA
+        value: "$(params.commit-sha)"
+      - name: TEKTON_BRANCH
+        value: "$(params.branch)"
+      - name: TEKTON_PULL_REQUEST          # optional
+        value: "$(params.pr-number)"
+```
+
+### Argo Workflows
+
+```yaml
+- name: percy
+  container:
+    image: node:20
+    env:
+      - name: ARGO_WORKFLOW_NAME           # required — triggers detection
+        value: "{{workflow.name}}"
+      - name: ARGO_WORKFLOW_UID            # recommended — used as parallel nonce
+        value: "{{workflow.uid}}"
+      - name: ARGO_COMMIT_SHA
+        value: "{{workflow.parameters.commit-sha}}"
+      - name: ARGO_BRANCH
+        value: "{{workflow.parameters.branch}}"
+      - name: ARGO_PULL_REQUEST            # optional
+        value: "{{workflow.parameters.pr-number}}"
+```
+
+### Vercel
+
+Vercel exposes its `VERCEL_*` system environment variables to the build step only
+when **Automatically expose System Environment Variables** is enabled on the project
+(Settings → Environment Variables). Percy also needs `PERCY_PARALLEL_TOTAL=-1`
+set in the project environment for the parallel nonce to populate from
+`VERCEL_DEPLOYMENT_ID` — otherwise reruns of the same deploy will create separate
+Percy builds instead of deduping.
 
 ## Percy Environment Variables
 
diff --git a/packages/env/src/environment.js b/packages/env/src/environment.js
index 859169b87..222b51d35 100644
--- a/packages/env/src/environment.js
+++ b/packages/env/src/environment.js
@@ -23,6 +23,8 @@ export class PercyEnv {
       return 'circle';
     } else if (this.vars.CI_NAME === 'codeship') {
       return 'codeship';
+    } else if (this.vars.CI_SYSTEM_NAME === 'woodpecker' || this.vars.CI === 'woodpecker') {
+      return 'woodpecker';
     } else if (this.vars.DRONE === 'true') {
       return 'drone';
     } else if (this.vars.SEMAPHORE === 'true') {
@@ -47,6 +49,28 @@ export class PercyEnv {
       return 'netlify';
     } else if (this.vars.HARNESS_PROJECT_ID) {
       return 'harness';
+    } else if (this.vars.TEAMCITY_VERSION) {
+      return 'teamcity';
+    } else if (this.vars.CODEBUILD_BUILD_ID) {
+      return 'aws-codebuild';
+    } else if (this.vars.bamboo_buildKey) {
+      return 'bamboo';
+    } else if (this.vars.BITRISE_IO === 'true') {
+      return 'bitrise';
+    } else if (this.vars.CM_BUILD_ID) {
+      return 'codemagic';
+    } else if (this.vars.VERCEL === '1') {
+      return 'vercel';
+    } else if (this.vars.CF_PAGES === '1') {
+      return 'cloudflare-pages';
+    } else if (this.vars.GO_PIPELINE_NAME && this.vars.GO_SERVER_URL) {
+      return 'gocd';
+    } else if (this.vars.BUILD_ID && this.vars.PROJECT_ID && !this.vars.JENKINS_URL) {
+      return 'gcb';
+    } else if (this.vars.TEKTON_PIPELINE_RUN) {
+      return 'tekton';
+    } else if (this.vars.ARGO_WORKFLOW_NAME) {
+      return 'argo-workflows';
     } else if (this.vars.CI) {
       return 'CI/unknown';
     } else {
@@ -109,6 +133,30 @@ export class PercyEnv {
           return github(this.vars).pull_request?.head.sha || this.vars.GITHUB_SHA;
         case 'harness':
           return this.vars.DRONE_COMMIT_SHA;
+        case 'woodpecker':
+          return this.vars.CI_COMMIT_SHA;
+        case 'teamcity':
+          return this.vars.BUILD_VCS_NUMBER;
+        case 'aws-codebuild':
+          return this.vars.CODEBUILD_RESOLVED_SOURCE_VERSION;
+        case 'bamboo':
+          return this.vars.bamboo_planRepository_revision;
+        case 'bitrise':
+          return this.vars.BITRISE_GIT_COMMIT;
+        case 'codemagic':
+          return this.vars.CM_COMMIT;
+        case 'vercel':
+          return this.vars.VERCEL_GIT_COMMIT_SHA;
+        case 'cloudflare-pages':
+          return this.vars.CF_PAGES_COMMIT_SHA;
+        case 'gocd':
+          return this.vars.GO_REVISION;
+        case 'gcb':
+          return this.vars.COMMIT_SHA;
+        case 'tekton':
+          return this.vars.TEKTON_COMMIT_SHA;
+        case 'argo-workflows':
+          return this.vars.ARGO_COMMIT_SHA;
       }
     })();
 
@@ -157,6 +205,26 @@ export class PercyEnv {
           return this.vars.HEAD;
         case 'harness':
           return this.vars.DRONE_SOURCE_BRANCH || this.vars.DRONE_COMMIT_BRANCH;
+        case 'woodpecker':
+          return this.vars.CI_COMMIT_BRANCH;
+        case 'aws-codebuild':
+          return this.vars.CODEBUILD_WEBHOOK_HEAD_REF;
+        case 'bamboo':
+          return this.vars.bamboo_planRepository_branchName;
+        case 'bitrise':
+          return this.vars.BITRISE_GIT_BRANCH;
+        case 'codemagic':
+          return this.vars.CM_BRANCH;
+        case 'vercel':
+          return this.vars.VERCEL_GIT_COMMIT_REF;
+        case 'cloudflare-pages':
+          return this.vars.CF_PAGES_BRANCH;
+        case 'gcb':
+          return this.vars.BRANCH_NAME;
+        case 'tekton':
+          return this.vars.TEKTON_BRANCH;
+        case 'argo-workflows':
+          return this.vars.ARGO_BRANCH;
       }
     })();
 
@@ -203,6 +271,24 @@ export class PercyEnv {
           return github(this.vars).pull_request?.number;
         case 'harness':
           return this.vars.DRONE_BUILD_EVENT === 'pull_request' && this.vars.DRONE_COMMIT_LINK?.split('/').slice(-1)[0];
+        case 'woodpecker':
+          return this.vars.CI_PIPELINE_EVENT === 'pull_request' && this.vars.CI_COMMIT_PULL_REQUEST;
+        case 'aws-codebuild':
+          return this.vars.CODEBUILD_WEBHOOK_TRIGGER?.match(/^pr\/(\d+)$/)?.[1];
+        case 'bamboo':
+          return this.vars.bamboo_repository_pr_key;
+        case 'bitrise':
+          return this.vars.BITRISE_PULL_REQUEST;
+        case 'codemagic':
+          return this.vars.CM_PULL_REQUEST === 'true' && this.vars.CM_PULL_REQUEST_NUMBER;
+        case 'vercel':
+          return this.vars.VERCEL_GIT_PULL_REQUEST_ID;
+        case 'gcb':
+          return this.vars._PR_NUMBER;
+        case 'tekton':
+          return this.vars.TEKTON_PULL_REQUEST;
+        case 'argo-workflows':
+          return this.vars.ARGO_PULL_REQUEST;
       }
     })();
 
@@ -261,6 +347,32 @@ export class PercyEnv {
           return this.vars.GITHUB_RUN_ID;
         case 'harness':
           return this.vars.HARNESS_BUILD_ID;
+        case 'woodpecker':
+          return this.vars.CI_PIPELINE_NUMBER;
+        case 'teamcity':
+          return this.vars.BUILD_NUMBER;
+        case 'aws-codebuild':
+          return this.vars.CODEBUILD_BUILD_ID;
+        case 'bamboo':
+          return this.vars.bamboo_buildResultKey;
+        case 'bitrise':
+          return this.vars.BITRISE_BUILD_NUMBER;
+        case 'codemagic':
+          return this.vars.CM_BUILD_ID;
+        case 'vercel':
+          return this.vars.VERCEL_DEPLOYMENT_ID;
+        case 'cloudflare-pages':
+          return this.vars.CF_PAGES_COMMIT_SHA || null;
+        case 'gocd':
+          return this.vars.GO_PIPELINE_COUNTER && this.vars.GO_STAGE_COUNTER
+            ? `${this.vars.GO_PIPELINE_COUNTER}.${this.vars.GO_STAGE_COUNTER}`
+            : this.vars.GO_PIPELINE_COUNTER;
+        case 'gcb':
+          return this.vars.BUILD_ID;
+        case 'tekton':
+          return this.vars.TEKTON_PIPELINE_RUN;
+        case 'argo-workflows':
+          return this.vars.ARGO_WORKFLOW_UID || this.vars.ARGO_WORKFLOW_NAME;
       }
     })();
 
diff --git a/packages/env/test/argo-workflows.test.js b/packages/env/test/argo-workflows.test.js
new file mode 100644
index 000000000..a77ece860
--- /dev/null
+++ b/packages/env/test/argo-workflows.test.js
@@ -0,0 +1,54 @@
+import PercyEnv from '@percy/env';
+
+describe('Argo Workflows', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      ARGO_WORKFLOW_NAME: 'my-workflow-42',
+      ARGO_WORKFLOW_UID: 'argo-uid-xyz',
+      ARGO_COMMIT_SHA: 'argo-commit-sha',
+      ARGO_BRANCH: 'argo-branch'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'argo-workflows');
+    expect(env).toHaveProperty('commit', 'argo-commit-sha');
+    expect(env).toHaveProperty('branch', 'argo-branch');
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'argo-uid-xyz');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR triggers', () => {
+    env = new PercyEnv({ ...env.vars, ARGO_PULL_REQUEST: '42' });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('falls back to workflow name when UID is absent', () => {
+    env = new PercyEnv({ ...env.vars, ARGO_WORKFLOW_UID: undefined });
+    expect(env).toHaveProperty('parallel.nonce', 'my-workflow-42');
+  });
+
+  it('is not detected when ARGO_WORKFLOW_NAME is unset (opt-in)', () => {
+    env = new PercyEnv({
+      ARGO_WORKFLOW_UID: 'argo-uid-xyz',
+      ARGO_COMMIT_SHA: 'argo-commit-sha'
+    });
+    expect(env).toHaveProperty('ci', null);
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/aws-codebuild.test.js b/packages/env/test/aws-codebuild.test.js
new file mode 100644
index 000000000..d4c813840
--- /dev/null
+++ b/packages/env/test/aws-codebuild.test.js
@@ -0,0 +1,64 @@
+import PercyEnv from '@percy/env';
+
+describe('AWS CodeBuild', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      CODEBUILD_BUILD_ID: 'codebuild:build-id',
+      CODEBUILD_RESOLVED_SOURCE_VERSION: 'codebuild-commit-sha',
+      CODEBUILD_WEBHOOK_HEAD_REF: 'refs/heads/codebuild-branch',
+      CODEBUILD_WEBHOOK_TRIGGER: 'branch/codebuild-branch'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'aws-codebuild');
+    expect(env).toHaveProperty('commit', 'codebuild-commit-sha');
+    expect(env).toHaveProperty('branch', 'codebuild-branch');
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'codebuild:build-id');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('parses pull-request number from CODEBUILD_WEBHOOK_TRIGGER', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      CODEBUILD_WEBHOOK_TRIGGER: 'pr/42'
+    });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('does not misattribute tag triggers as pull requests', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      CODEBUILD_WEBHOOK_TRIGGER: 'tag/v1.0.0'
+    });
+    expect(env).toHaveProperty('pullRequest', null);
+  });
+
+  it('returns null for branch and PR on manual or EventBridge triggers (no webhook vars)', () => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      CODEBUILD_BUILD_ID: 'codebuild:build-id',
+      CODEBUILD_RESOLVED_SOURCE_VERSION: 'codebuild-commit-sha'
+    });
+    expect(env).toHaveProperty('ci', 'aws-codebuild');
+    expect(env).toHaveProperty('commit', 'codebuild-commit-sha');
+    expect(env).toHaveProperty('branch', null);
+    expect(env).toHaveProperty('pullRequest', null);
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/bamboo.test.js b/packages/env/test/bamboo.test.js
new file mode 100644
index 000000000..8afacb551
--- /dev/null
+++ b/packages/env/test/bamboo.test.js
@@ -0,0 +1,46 @@
+import PercyEnv from '@percy/env';
+
+describe('Bamboo', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      bamboo_buildKey: 'PROJ-PLAN-JOB',
+      bamboo_planRepository_revision: 'bamboo-commit-sha',
+      bamboo_planRepository_branchName: 'bamboo-branch',
+      bamboo_buildResultKey: 'PROJ-PLAN-JOB-42',
+      bamboo_buildNumber: '42'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'bamboo');
+    expect(env).toHaveProperty('commit', 'bamboo-commit-sha');
+    expect(env).toHaveProperty('branch', 'bamboo-branch');
+    expect(env).toHaveProperty('pullRequest', null);
+    // buildResultKey (not buildNumber) so reruns don't collide
+    expect(env).toHaveProperty('parallel.nonce', 'PROJ-PLAN-JOB-42');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR builds', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      bamboo_repository_pr_key: '7'
+    });
+    expect(env).toHaveProperty('pullRequest', '7');
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/bitrise.test.js b/packages/env/test/bitrise.test.js
new file mode 100644
index 000000000..10cdf227e
--- /dev/null
+++ b/packages/env/test/bitrise.test.js
@@ -0,0 +1,43 @@
+import PercyEnv from '@percy/env';
+
+describe('Bitrise', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      BITRISE_IO: 'true',
+      BITRISE_GIT_COMMIT: 'bitrise-commit-sha',
+      BITRISE_GIT_BRANCH: 'bitrise-branch',
+      BITRISE_PULL_REQUEST: '',
+      BITRISE_BUILD_NUMBER: 'bitrise-build-number'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'bitrise');
+    expect(env).toHaveProperty('commit', 'bitrise-commit-sha');
+    expect(env).toHaveProperty('branch', 'bitrise-branch');
+    // Bitrise sets empty string on non-PR builds
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'bitrise-build-number');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR builds', () => {
+    env = new PercyEnv({ ...env.vars, BITRISE_PULL_REQUEST: '42' });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/cloudflare-pages.test.js b/packages/env/test/cloudflare-pages.test.js
new file mode 100644
index 000000000..996e4b4f7
--- /dev/null
+++ b/packages/env/test/cloudflare-pages.test.js
@@ -0,0 +1,49 @@
+import PercyEnv from '@percy/env';
+
+describe('Cloudflare Pages', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      CF_PAGES: '1',
+      CF_PAGES_COMMIT_SHA: 'cf-commit-sha',
+      CF_PAGES_BRANCH: 'cf-branch',
+      CF_PAGES_URL: 'https://abc123.my-project.pages.dev'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'cloudflare-pages');
+    expect(env).toHaveProperty('commit', 'cf-commit-sha');
+    expect(env).toHaveProperty('branch', 'cf-branch');
+    // Cloudflare Pages does not natively expose PR info
+    expect(env).toHaveProperty('pullRequest', null);
+    // Nonce is commit SHA alone — earlier composite (commit + URL) exceeded
+    // Percy's 64-char nonce limit and caused build creation to fail.
+    expect(env).toHaveProperty('parallel.nonce', 'cf-commit-sha');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('returns null nonce when CF_PAGES_COMMIT_SHA is absent (never emits "undefined")', () => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      CF_PAGES: '1',
+      CF_PAGES_BRANCH: 'cf-branch',
+      CF_PAGES_URL: 'https://abc123.my-project.pages.dev'
+    });
+    expect(env).toHaveProperty('parallel.nonce', null);
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/codemagic.test.js b/packages/env/test/codemagic.test.js
new file mode 100644
index 000000000..dac6da53a
--- /dev/null
+++ b/packages/env/test/codemagic.test.js
@@ -0,0 +1,55 @@
+import PercyEnv from '@percy/env';
+
+describe('Codemagic', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      CM_BUILD_ID: 'codemagic-build-uuid',
+      CM_COMMIT: 'codemagic-commit-sha',
+      CM_BRANCH: 'codemagic-branch',
+      CM_PULL_REQUEST: 'false'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'codemagic');
+    expect(env).toHaveProperty('commit', 'codemagic-commit-sha');
+    expect(env).toHaveProperty('branch', 'codemagic-branch');
+    // CM_PULL_REQUEST === 'false' (string) means non-PR build
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'codemagic-build-uuid');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR builds', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      CM_PULL_REQUEST: 'true',
+      CM_PULL_REQUEST_NUMBER: '42'
+    });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('ignores CM_PULL_REQUEST_NUMBER when CM_PULL_REQUEST is the string "false"', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      CM_PULL_REQUEST: 'false',
+      CM_PULL_REQUEST_NUMBER: '42'
+    });
+    expect(env).toHaveProperty('pullRequest', null);
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/gcb.test.js b/packages/env/test/gcb.test.js
new file mode 100644
index 000000000..53b53ae41
--- /dev/null
+++ b/packages/env/test/gcb.test.js
@@ -0,0 +1,63 @@
+import PercyEnv from '@percy/env';
+
+describe('Google Cloud Build', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      BUILD_ID: 'gcb-build-id',
+      PROJECT_ID: 'my-gcp-project',
+      COMMIT_SHA: 'gcb-commit-sha',
+      BRANCH_NAME: 'gcb-branch'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'gcb');
+    expect(env).toHaveProperty('commit', 'gcb-commit-sha');
+    expect(env).toHaveProperty('branch', 'gcb-branch');
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'gcb-build-id');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR triggers', () => {
+    env = new PercyEnv({ ...env.vars, _PR_NUMBER: '42' });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('returns null commit/branch/PR on manual gcloud submits (no trigger vars)', () => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      BUILD_ID: 'gcb-build-id',
+      PROJECT_ID: 'my-gcp-project'
+    });
+    expect(env).toHaveProperty('ci', 'gcb');
+    expect(env).toHaveProperty('commit', null);
+    expect(env).toHaveProperty('branch', null);
+    expect(env).toHaveProperty('pullRequest', null);
+  });
+
+  it('does not match when JENKINS_URL is also set (Jenkins wins)', () => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      JENKINS_URL: 'https://jenkins.example.com',
+      BUILD_ID: 'jenkins-build-id',
+      PROJECT_ID: 'my-gcp-project'
+    });
+    expect(env).toHaveProperty('ci', 'jenkins');
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/gocd.test.js b/packages/env/test/gocd.test.js
new file mode 100644
index 000000000..35cb8cc6b
--- /dev/null
+++ b/packages/env/test/gocd.test.js
@@ -0,0 +1,61 @@
+import PercyEnv from '@percy/env';
+
+describe('GoCD', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      GO_PIPELINE_NAME: 'my-pipeline',
+      GO_SERVER_URL: 'https://gocd.example.com',
+      GO_REVISION: 'gocd-commit-sha',
+      GO_PIPELINE_COUNTER: '42',
+      GO_STAGE_COUNTER: '1'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'gocd');
+    expect(env).toHaveProperty('commit', 'gocd-commit-sha');
+    // GoCD does not expose branch/PR via standard env vars
+    expect(env).toHaveProperty('branch', null);
+    expect(env).toHaveProperty('pullRequest', null);
+    // Composite pipeline.stage counter to survive stage reruns
+    expect(env).toHaveProperty('parallel.nonce', '42.1');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('nonce changes when the stage counter bumps on rerun', () => {
+    env = new PercyEnv({ ...env.vars, GO_STAGE_COUNTER: '2' });
+    expect(env).toHaveProperty('parallel.nonce', '42.2');
+  });
+
+  it('falls back to pipeline counter alone when stage counter is absent', () => {
+    env = new PercyEnv({ ...env.vars, GO_STAGE_COUNTER: undefined });
+    expect(env).toHaveProperty('parallel.nonce', '42');
+  });
+
+  it('returns null commit on multi-material pipelines (GO_REVISION unset)', () => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      GO_PIPELINE_NAME: 'my-pipeline',
+      GO_SERVER_URL: 'https://gocd.example.com',
+      GO_PIPELINE_COUNTER: '42',
+      GO_STAGE_COUNTER: '1'
+    });
+    expect(env).toHaveProperty('ci', 'gocd');
+    expect(env).toHaveProperty('commit', null);
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/teamcity.test.js b/packages/env/test/teamcity.test.js
new file mode 100644
index 000000000..028afe718
--- /dev/null
+++ b/packages/env/test/teamcity.test.js
@@ -0,0 +1,47 @@
+import PercyEnv from '@percy/env';
+
+describe('TeamCity', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      TEAMCITY_VERSION: '2024.07',
+      BUILD_VCS_NUMBER: 'teamcity-commit-sha',
+      BUILD_NUMBER: 'teamcity-build-number'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'teamcity');
+    expect(env).toHaveProperty('commit', 'teamcity-commit-sha');
+    // TeamCity does not expose branch/PR via standard env vars
+    expect(env).toHaveProperty('branch', null);
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'teamcity-build-number');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('returns null commit when only the multi-root suffixed var is set', () => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      TEAMCITY_VERSION: '2024.07',
+      BUILD_VCS_NUMBER_Repo1: 'teamcity-multi-root-sha',
+      BUILD_NUMBER: 'teamcity-build-number'
+    });
+    expect(env).toHaveProperty('ci', 'teamcity');
+    expect(env).toHaveProperty('commit', null);
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/tekton.test.js b/packages/env/test/tekton.test.js
new file mode 100644
index 000000000..43d11800e
--- /dev/null
+++ b/packages/env/test/tekton.test.js
@@ -0,0 +1,48 @@
+import PercyEnv from '@percy/env';
+
+describe('Tekton Pipelines', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      TEKTON_PIPELINE_RUN: 'my-pipeline-run-42',
+      TEKTON_COMMIT_SHA: 'tekton-commit-sha',
+      TEKTON_BRANCH: 'tekton-branch'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'tekton');
+    expect(env).toHaveProperty('commit', 'tekton-commit-sha');
+    expect(env).toHaveProperty('branch', 'tekton-branch');
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'my-pipeline-run-42');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR triggers', () => {
+    env = new PercyEnv({ ...env.vars, TEKTON_PULL_REQUEST: '42' });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('is not detected when TEKTON_PIPELINE_RUN is unset (opt-in)', () => {
+    env = new PercyEnv({
+      TEKTON_COMMIT_SHA: 'tekton-commit-sha',
+      TEKTON_BRANCH: 'tekton-branch'
+    });
+    expect(env).toHaveProperty('ci', null);
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/vercel.test.js b/packages/env/test/vercel.test.js
new file mode 100644
index 000000000..269c9fce7
--- /dev/null
+++ b/packages/env/test/vercel.test.js
@@ -0,0 +1,48 @@
+import PercyEnv from '@percy/env';
+
+describe('Vercel', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      VERCEL: '1',
+      VERCEL_GIT_COMMIT_SHA: 'vercel-commit-sha',
+      VERCEL_GIT_COMMIT_REF: 'vercel-branch',
+      VERCEL_GIT_PULL_REQUEST_ID: '',
+      VERCEL_DEPLOYMENT_ID: 'dpl_vercel-deployment-id'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'vercel');
+    expect(env).toHaveProperty('commit', 'vercel-commit-sha');
+    expect(env).toHaveProperty('branch', 'vercel-branch');
+    // Empty string when branch has no PR yet or on production deploys
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'dpl_vercel-deployment-id');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR builds', () => {
+    env = new PercyEnv({ ...env.vars, VERCEL_GIT_PULL_REQUEST_ID: '42' });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('falls through to CI/unknown when system env vars are not exposed (checkbox off)', () => {
+    env = new PercyEnv({ CI: 'true' });
+    expect(env).toHaveProperty('ci', 'CI/unknown');
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});
diff --git a/packages/env/test/woodpecker.test.js b/packages/env/test/woodpecker.test.js
new file mode 100644
index 000000000..13b79d0e1
--- /dev/null
+++ b/packages/env/test/woodpecker.test.js
@@ -0,0 +1,67 @@
+import PercyEnv from '@percy/env';
+
+describe('Woodpecker', () => {
+  let env;
+
+  beforeEach(() => {
+    env = new PercyEnv({
+      PERCY_PARALLEL_TOTAL: '-1',
+      CI_SYSTEM_NAME: 'woodpecker',
+      CI: 'woodpecker',
+      CI_COMMIT_SHA: 'woodpecker-commit-sha',
+      CI_COMMIT_BRANCH: 'woodpecker-branch',
+      CI_PIPELINE_NUMBER: 'woodpecker-pipeline-number'
+    });
+  });
+
+  it('has the correct properties', () => {
+    expect(env).toHaveProperty('ci', 'woodpecker');
+    expect(env).toHaveProperty('commit', 'woodpecker-commit-sha');
+    expect(env).toHaveProperty('branch', 'woodpecker-branch');
+    expect(env).toHaveProperty('target.commit', null);
+    expect(env).toHaveProperty('target.branch', null);
+    expect(env).toHaveProperty('pullRequest', null);
+    expect(env).toHaveProperty('parallel.nonce', 'woodpecker-pipeline-number');
+    expect(env).toHaveProperty('parallel.total', -1);
+  });
+
+  it('has the correct properties for PR builds', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      CI_PIPELINE_EVENT: 'pull_request',
+      CI_COMMIT_PULL_REQUEST: '42'
+    });
+    expect(env).toHaveProperty('pullRequest', '42');
+  });
+
+  it('ignores CI_COMMIT_PULL_REQUEST on non-pull_request events', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      CI_PIPELINE_EVENT: 'push',
+      CI_COMMIT_PULL_REQUEST: '42'
+    });
+    expect(env).toHaveProperty('pullRequest', null);
+  });
+
+  it('wins over Drone when Drone-compat vars are also set', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      DRONE: 'true',
+      DRONE_COMMIT: 'drone-commit'
+    });
+    expect(env).toHaveProperty('ci', 'woodpecker');
+    expect(env).toHaveProperty('commit', 'woodpecker-commit-sha');
+  });
+
+  it('respects PERCY_* overrides', () => {
+    env = new PercyEnv({
+      ...env.vars,
+      PERCY_COMMIT: 'override-commit',
+      PERCY_BRANCH: 'override-branch',
+      PERCY_PULL_REQUEST: '999'
+    });
+    expect(env).toHaveProperty('commit', 'override-commit');
+    expect(env).toHaveProperty('branch', 'override-branch');
+    expect(env).toHaveProperty('pullRequest', '999');
+  });
+});