Compare / Semaphore vs GitLab CI
Semaphore vs GitLab CI
Keep GitLab for code and merge requests, and use Semaphore as the CI/CD execution layer. This page compares them on speed, cost, self-hosting and debugging.
TL;DR
- Average build time: 5m 01s on Semaphore vs 11m 15s on GitLab CI. Cost per job: $0.04 vs $0.11.
- Code and merge requests stay on GitLab. Only the CI changes.
- Pay-as-you-go compute, separate from support tiers.
- Self-host Community Edition (open source) or run Enterprise Edition behind your firewall.
- GitLab CI fits better if you want code, CI and planning in one product (details).
At a glance
| Semaphore | GitLab CI | |
|---|---|---|
| Average build time | 5m 01s | 11m 15s |
| Cost per job | $0.04 | $0.11 |
| Source control | Connects to GitLab and other Git hosts | Native |
| Pipeline config | Pipeline as code plus a visual editor | .gitlab-ci.yml |
| Managed execution | Autoscaling cloud machines | Instance runners, by plan and compute usage |
| Self-hosting | Community Edition or Enterprise Edition | GitLab Self-Managed plus your own runners |
| Debugging | Real-time logs, SSH into jobs | Job logs and pipeline tooling |
| Test signals | Test reports and flaky-test detection built in | Test reports, depending on configuration and plan |
| Coding agents | sem-ai CLI and MCP server | GitLab Duo Agent Platform |
Benchmark
Average build time for the same Redmine workflow on 2 vCPU / 8 GB machines, 10 warmed-cache runs, March 2026. Lower is better.
Benchmark run by Semaphore on one workload. Validate it on your own pipeline. Methodology and raw data →
Config side by side
The same Node.js test pipeline in both tools.
.gitlab-ci.yml
test:
image: node:20
script:
- npm ci
- npm test.semaphore/semaphore.yml
version: v1.0
name: CI
agent:
machine:
type: f1-standard-2
os_image: ubuntu2404
blocks:
- name: Test
task:
jobs:
- name: npm test
commands:
- checkout
- sem-version node 20
- npm ci
- npm testMigrating
Install the sem-ai CLI, then ask your coding agent to recreate the pipeline. Run both side by side before you switch.
$ curl -fsSL https://raw.githubusercontent.com/semaphoreio/sem-ai/main/install.sh | sh
# Claude Code
/plugin marketplace add semaphoreio/sem-ai
/plugin install sem-ai@semaphoreio
# Codex
codex plugin marketplace add semaphoreio/sem-ai
codex plugin add sem-ai@semaphoreio
# then ask your agent:
# "move this GitLab CI pipeline to Semaphore"- Pick one representative project.
- The agent recreates its pipeline in
.semaphore/semaphore.yml. - Connect the GitLab repository.
- Run both pipelines in parallel, then migrate project by project.
When GitLab CI fits better
- You want code hosting, CI, planning and security scanning in one product.
- Your team is already standardized on GitLab Ultimate features.
FAQ
No. Semaphore connects to GitLab repositories, so you can keep GitLab for code hosting, merge requests and review while using Semaphore for CI/CD execution.
Semaphore’s March 2026 benchmark reported 5m 01s versus 11m 15s on GitLab CI for one warmed-cache Redmine workflow. It is a vendor-run result for one workload, not a universal guarantee. Validate with a parallel proof of concept on your own pipeline.
Yes. Semaphore Community Edition is free and open source. Semaphore Enterprise Edition can run on your infrastructure behind a firewall.
Yes. The sem-ai CLI and MCP integration are designed to let coding agents inspect structured CI/CD context and help with setup, debugging and workflow maintenance. Keep credentials scoped and production approvals human-controlled.
Start with one representative pipeline
Keep GitLab for code.
Measure a better CI/CD layer.
curl -fsSL https://raw.githubusercontent.com/semaphoreio/sem-ai/main/install.sh | sh/plugin marketplace add semaphoreio/sem-ai/plugin install sem-ai@semaphoreiocodex plugin marketplace add semaphoreio/sem-aicodex plugin add sem-ai@semaphoreioBring one representative pipeline to Semaphore. Compare the same workload, then decide based on the evidence.