Know what every error means, and how to fix it.
ErrLookup reads library source and documents every user-facing error: exact message, cause, ordered fixes, defensive patterns. Built for coding agents, answer engines, and humans.
504,328errors documented
2311repositories
2026-09-23dataset version
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Analyzed repos
2,311 repositories, most-documented first — page 1 of 78.
| Repo | Language | Errors | Source files |
|---|---|---|---|
| weaviate/weaviate | Go | 5976 | 2,902 |
| apache/beam | Java | 5177 | 5,758 |
| dagger/dagger | Go | 5026 | 1,857 |
| jackwener/OpenCLI | JavaScript | 4683 | 1,570 |
| apache/hadoop | Java | 4312 | 9,121 |
| flowable/flowable-engine | Java | 4276 | 5,483 |
| nautechsystems/nautilus_trader | Rust | 4109 | 2,539 |
| moodle/moodle | PHP | 3730 | 50,387 |
| kubernetes/kops | Go | 3699 | 1,363 |
| cilium/cilium | Go | 3555 | 3,339 |
| BerriAI/litellm | Python | 3524 | 3,789 |
| deeplearning4j/deeplearning4j | Java | 3512 | 5,685 |
| pentaho/pentaho-kettle | Java | 3509 | 3,739 |
| quarkusio/quarkus | Java | 3471 | 12,631 |
| dotnet/wpf | C# | 3455 | 5,703 |
| sgl-project/sglang | Python | 3398 | 3,697 |
| pulumi/pulumi | Go | 3358 | 1,595 |
| apache/iceberg | Java | 3257 | 3,953 |
| Hmbown/CodeWhale | Rust | 3249 | 1,437 |
| gastownhall/beads | Go | 3225 | 1,245 |
| apache/cassandra | Java | 3118 | 3,424 |
| hashicorp/nomad | Go | 3049 | 2,030 |
| can1357/oh-my-pi | TypeScript | 3019 | 2,728 |
| apache/seatunnel | Java | 2966 | 4,131 |
| hibernate/hibernate-orm | Java | 2940 | 7,647 |
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