Source: https://seerepo.com/compare/iii-hq/iii/vs/unionlabs/union
Markdown source: https://seerepo.com/compare/iii-hq/iii/vs/unionlabs/union.md
Description: iii and union share 11 technologies: axum, tower, SQLite, Tokio, console, schemars, tracing, OpenTelemetry, tracing-subscriber, tracing-opentelemetry, and opentelemetry-otlp. Both are written in Rust.

# iii vs union

iii and union share 11 technologies: axum, tower, SQLite, Tokio, console, schemars, tracing, OpenTelemetry, tracing-subscriber, tracing-opentelemetry, and opentelemetry-otlp. Both are written in Rust.

- [iii-hq/iii](https://seerepo.com/r/iii-hq/iii): Effortlessly compose, extend, and observe every service in real-time for the first time ever.
- [unionlabs/union](https://seerepo.com/r/unionlabs/union): The trust-minimized, zero-knowledge bridging protocol, designed for censorship resistance, extremely high security, and usage in decentralized finance.

## What they share and what sets them apart

- In common: axum, tower, SQLite, Tokio, console, schemars, tracing, OpenTelemetry, tracing-subscriber, tracing-opentelemetry, opentelemetry-otlp
- Only in iii: React, rusqlite, lapin, Redis, indicatif, cliclack, zip, Pydantic, jsonschema, github.com/invopop/jsonschema, opentelemetry-api, go.opentelemetry.io/otel, go.opentelemetry.io/otel/trace, go.opentelemetry.io/otel/sdk, go.opentelemetry.io/otel/metric, go.opentelemetry.io/otel/log, go.opentelemetry.io/otel/sdk/log, go.opentelemetry.io/otel/sdk/metric, opentelemetry-sdk, opentelemetry-http
- Only in union: net/http, Gorilla, sqlx-postgres, Postgres, moka, sqlx, wasmtime, Svelte, SvelteKit, Supabase, @effect/platform, Ratatui, crossterm, ed25519-dalek, github.com/rs/zerolog, Tailwind CSS, tailwind-merge, rehype-stringify, remark, remark-parse, unified, vfile, @effect/opentelemetry

## Side by side

| | iii | union |
|---|---|---|
| Size | 523,734 lines written, 690 code files | 468,416 lines written, 1,841 code files |
| Who writes it | 4.9% of its commits signed by AI. With Claude Code, CodeRabbit, Cursor, and GitHub Copilot | 0% of its commits signed by AI. With CodeRabbit |
| Activity | Last push November 6, 2026, 2,181 commits, 18,926 stars | Last push July 25, 2026, 13,299 commits, 73,725 stars |
| Tests | 452 test files. 21.4% of its code files have a test that imports them | 120 test files. 10.4% of its code files have a test that imports them |

- Size: Lines written by people and agents, without generated ones; code files, without tests.
- Who writes it: A commit counts as AI's when it carries its signature: a Co-Authored-By line, its author name or the merge of its branch.
- Activity: From GitHub and its history, on the day SeeRepo read it.
- Tests: The files that test the code, and the share of code files a test imports.

## Frequently asked questions

### Which is bigger, iii or union?

iii, with 523,734 lines written; union has 468,416.

The proof: [iii-hq/iii's code at commit 4094bb4](https://github.com/iii-hq/iii/tree/4094bb423d98f87ebef8fa7347891fbc485b71db)

### Which has more GitHub stars, iii or union?

union, with 73,725 stars; iii has 18,926.

The proof: [unionlabs/union on GitHub](https://github.com/unionlabs/union)

### Which has more tests, iii or union?

iii, with 452 test files; union has 120.

The proof: [iii-hq/iii's code at commit 4094bb4](https://github.com/iii-hq/iii/tree/4094bb423d98f87ebef8fa7347891fbc485b71db)

### Which was updated more recently, iii or union?

iii: its last push was on November 6, 2026, and union's on July 25, 2026.

The proof: [iii-hq/iii's commits on GitHub](https://github.com/iii-hq/iii/commits)

### Which has more commits signed by AI, iii or union?

iii: an AI signed 4.9% of its commits, with Claude Code, CodeRabbit, Cursor, and GitHub Copilot.

The proof: [the commits each tool signed in iii-hq/iii](https://seerepo.com/r/iii-hq/iii/ai)

## Sources

- iii-hq/iii: Read on November 6, 2026, at commit 4094bb4 (https://github.com/iii-hq/iii/tree/4094bb423d98f87ebef8fa7347891fbc485b71db)
- unionlabs/union: Read on November 5, 2026, at commit 031785b (https://github.com/unionlabs/union/tree/031785bb6dc6b957c624e62bc64c184409c97d7b)

## What is your repo built with?

Any public repo, with no account: https://seerepo.com/r/owner/repo/built, with the owner and name it has on GitHub.