{"adoption": {"forks": 117, "observed_at": "2026-08-28T04:06:34.953280+00:00", "stars": 2291}, "canonical_url": "https://ross.abutalabs.com/products/fjall", "card": {"archived": false, "artifact_type": "library", "description": "🗻 Log-structured, embeddable key-value storage engine written in Rust", "domain": ["databases", "developer-tools", "backend"], "enriched": true, "function": ["database", "serialization", "caching"], "health_score": 100, "homepage": "https://fjall-rs.github.io", "language": "Rust", "license": "Apache-2.0", "license_family": "permissive", "maturity": "active", "member_repos": ["fjall-rs/fjall"], "name": "fjall-rs/fjall", "platform": ["rust", "cross-platform"], "pushed_at": "2026-08-24T16:05:46+00:00", "repo": "fjall-rs/fjall", "stars": 2291, "tags": ["lsm-tree", "key-value-store", "embedded-database", "storage-engine", "keyspace", "transactions", "compression"], "topics": ["database", "lsm", "lsm-tree", "lsmt", "rust", "rust-lang", "storage-engine", "embedded-database", "embedded-kv", "kv", "kv-database", "kv-storage", "kv-store", "log-structured", "log-structured-merge-tree", "key-value-database", "key-value-store", "embeddable", "embeddable-database", "key-value-storage"], "urls": [], "use_cases": ["embed a key-value store in a Rust application", "replace RocksDB or LevelDB with a pure-Rust storage engine", "store large blobs with key-value separation", "build a database or index on top of an LSM-tree engine", "run range and prefix scans with forward and reverse iteration", "use column-family-like keyspaces with atomic cross-keyspace writes", "need serializable transactions in an embedded store"], "what_it_is": "Fjall is a log-structured (LSM-tree-based), embeddable key-value storage engine written in 100% safe Rust, similar in spirit to RocksDB. It offers a thread-safe BTreeMap-like API with multiple keyspaces, range/prefix iteration, optional serializable transactions, built-in LZ4 compression, and key-value separation for large blobs.", "when_to_avoid": ["you need a standalone database server or network API", "you need a relational database, SQL, or query language", "your project is not in Rust"], "when_to_choose": ["you need an embeddable, serverless key-value engine in Rust", "you want RocksDB-like LSM performance without C++ dependencies", "you need multiple keyspaces, transactions, or blob separation in-process"]}, "data_as_of": "2026-08-30T08:39:29.467469+00:00", "members": [{"path": "/products/fjall", "repo": "fjall-rs/fjall", "role": "main", "score": 93}], "provenance": {"archived": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "artifact_type": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "description": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "domain": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "enriched": {"inputs": [], "kind": "computed", "method": "enrichment_status"}, "function": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "health_score": {"inputs": ["days_since_push", "days_since_release", "archived"], "kind": "computed", "method": "health_v1"}, "homepage": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "language": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "license": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "license_family": {"inputs": ["license"], "kind": "computed", "method": "license_family"}, "maturity": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "member_repos": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "name": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "platform": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "pushed_at": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "repo": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "stars": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "tags": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "topics": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "urls": {"kind": "observed", "observed_at": "2026-08-28T04:06:34.953280+00:00", "source": "github"}, "use_cases": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "what_it_is": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "when_to_avoid": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}, "when_to_choose": {"confidence": null, "enriched_at": "2026-08-30T02:40:40.689720+00:00", "kind": "inferred", "prompt_version": 1, "sources": [{"content_hash": "a39f76e9dbfea0c682ca7fde450ac53b2a5567c71ea22e726fcb28f897f04cdf", "fetched_at": "2026-08-28T04:06:34.953280+00:00", "kind": "readme", "missing": false, "url": "https://github.com/fjall-rs/fjall"}, {"content_hash": "6869644eb5c9d1ed4ebce302568b02de1254ecb082b82f7b021677c6bacd9b62", "fetched_at": "2026-08-29T10:20:52.353976+00:00", "kind": "homepage", "missing": false, "url": "https://fjall-rs.github.io"}, {"content_hash": "643fe52a26955168f18cb949881a242f77bb8d7052dfeb907b2331e6990c58df", "fetched_at": "2026-08-29T10:20:52.363026+00:00", "kind": "registry_crates", "missing": false, "url": "https://crates.io/api/v1/crates/fjall"}], "taxonomy_version": 1}}, "score": {"components": {"activity": 99, "longevity": 72, "rhythm": 98}, "computed_at": "2026-09-02T17:46:02.011165+00:00", "flags": [], "formula": "round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)", "inputs": {"age_days": 1021, "days_push": 9, "days_rel": 18, "gap_med": 5.5, "n_releases_24m": 53}, "score": 93, "version": 2}, "staleness": {"enrichment_outdated": false, "low_confidence": false, "scrape_days": 9, "stale_scrape": false}}