See what your API actually does.

MS Harness records every request your services make and return, then shows you what changed: a field that quietly became 40 % slower, a payload that grew 3 KB, a status code that drifts at night. Self-hosted, single binary, no sampling.

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Built for teams that ship daily

Behaviour diffs

Compare two deployments field by field. Schema, latency, size and error mix in one view — no dashboards to assemble.

4 MB agent

One static binary, zero dependencies, works on your smallest instance. Ships over UDP if you want, TCP if you don't.

Alerts that survive

Thresholds on behaviour, not just uptime. Get paged when a contract changes, not when a box reboots.

Your storage

Postgres, ClickHouse or plain Parquet on disk. Data never leaves your infrastructure unless you export it.

Three commands to a first trace

# install the collector
curl -fsSL https://msharness.online/install.sh | sh

# point it at your API
msharness collect --upstream http://127.0.0.1:8080 --db ./harness.db

harness recording 14 endpoints, sampling 100%

Pricing

Self-hosted

Free forever. One binary, unlimited requests, your database. Community support on GitHub.

Team — €19 / seat

Shared workspaces, SSO, retention policies and 90-day history. Billed monthly, cancel anytime.

Enterprise

Air-gapped installs, audit logs, custom retention and a named engineer on your channel.