Ross ROSS = Recommend OSS · open-source software intelligence for agents

opendiffy/diffy

None observed · 2026-08-28

github.com/opendiffy/diffy · Java · NOASSERTION (other) observed · 2026-08-28

Health v2 · maintenance only

60/100

  • Activity 83
  • Release rhythm 8
  • Longevity 100

Flags: no_license

How is this computed?

round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-02. Adoption (stars, forks) is never an input.

  • gap_med: n/a
  • age_days: 3051
  • days_rel: n/a
  • days_push: 107
  • n_releases_24m: 0

Full methodology

Adoption not part of the score

1461 stars · 164 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

Diffy is a differential testing tool that sends identical requests to a candidate service and a reference (primary/secondary) service, then diffs the responses to surface regressions without writing tests. It is a Java-based service used in production at companies like Twitter, Airbnb, and Mixpanel.

Use cases

  • safely rewrite a high-throughput service and verify behavior parity
  • run shadow testing when migrating between API gateways
  • catch regressions in a new service version before deploying it
  • compare candidate and reference service responses automatically
  • test microservices without writing test cases

When to choose

  • you are rewriting or migrating a service and need automated behavioral comparison
  • you want the shadow/differential testing pattern used by Twitter and Airbnb
  • you have both a stable reference service and a candidate service to compare

When to avoid

  • you need a general-purpose unit or integration test framework
  • you have no reference implementation to diff against
  • your license requires permissive open-source terms (license is CC BY-NC-ND)

Facets

service · maturity active

testing e2e-testing http-client developer-tools testing developer-tools apis microservices jvm cross-platform cli differential-testing shadow-testing regression-testing api-testing traffic-mirroring docker

1 source

Member repositories

RepositoryRoleHealth v2
opendiffy/diffymain60

For agents

markdown · JSON · MCP: product_card(name="opendiffy/diffy")

Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem