Glen

An embedded document database for Nim with first-class spatial, temporal, and numeric primitives — durable, concurrent, in-process.

import glen/db, glen/types

let db = newGlenDB("./mydb")
var alice = VObject()
alice["name"] = VString("Alice")
db.put("users", "u1", alice)
echo db.get("users", "u1")

Status: beta (0.5.0). On-disk formats are versioned (WAL v2; snapshot v3 with v1/v2 read-back; GRI/GPI v1; GTS/TTS v1). Expect minor API churn until 1.0.

What's inside

Core	Document model + WAL + snapshots, optimistic transactions, sharded LRU cache, striped per-collection RW-locks, multi-master replication (HLC, LWW), schema validation
Spatial	R-tree indexes for points and polygons, KNN with planar or geographic (haversine) metrics, point-in-polygon queries
Temporal	Gorilla-encoded scalar time-series engine; tile time-stacks for compressed raster-over-time storage
Numeric	Vector + Matrix primitives, GeoMesh (raster pinned to a bbox)
Scale	Spillable mode with paged on-disk doc index — datasets bigger than RAM via mmap; streaming iterators for bounded-memory bulk reads

No external runtime dependencies. Pure Nim ≥ 1.6.

Install

nimble install https://github.com/oshaulz/glen

or in a .nimble file:

requires "https://github.com/oshaulz/glen >= 0.5.0"

Documentation

Start here:

• Getting started — install, basic usage, common patterns
• Architecture — system overview, components, data flow

Topical:

• Storage and recovery — WAL, snapshot formats (v1/v2/v3)
• Concurrency model — striped RW locks, optimistic transactions, multi-master replication
• Spillable mode — datasets bigger than RAM, streaming iterators, paged on-disk index
• Performance — benchmarks, tradeoffs, what to expect

API reference:

• Core — db.put / get / delete, batch ops, transactions, equality / range indexes, subscriptions, replication, schema validation
• Spatial — geo points (R-tree), polygons, GeoMesh
• Time-series — Gorilla TSDB, tile time-stacks
• Numeric — Vector, Matrix, ops

For an architectural deep-dive, see WHITEPAPER.md. For agent / contributor guidance, see AGENT_GUIDE.md.

License

MIT. See LICENSE.