keel

Data model description engine. Business code defines resources, fields, and relations only. Control fields and control capabilities stay inside the engine. HTTP and store adaptors project the engine surface — they are not a business authoring API.

Canonical source: PerishLab/keel.

Cold start

use keel::adapt::db::Sqlite;
use keel::atom::string;
use keel::resource;
use keel::{Graph, bind};

#[resource]
struct Course {
    #[field(string)]
    code: string,
    #[field(string)]
    title: string,
}

#[resource]
struct Student {
    #[field(string)]
    no: string,
    #[field(string)]
    name: string,
    #[relation(Course, many2many)]
    courses: Course,
}

fn main() {
    let mut graph = Graph::new();
    graph.plug::<Course>().plug::<Student>();
    let core = bind(graph, Sqlite::memory()).expect("bind");
    let _id = core
        .put("Student", &[("no", "S01"), ("name", "ada")])
        .expect("put");
}

Engine face (Core)

Method	Meaning
put / set / live / end	insert, partial update, live list, soft-end
query / ask	text → AST → run; ask takes Tree directly
AST	from + where + link + order/page → always pack
tie / ties / cut	many2many write on Core; read via link bond bags (H0)
edge law	flat pack; root-only order/page — docs/model/edge.md
serve / listen	axum (http feature)

HTTP surface

Native REST per resource (no association queries):

Method	Path	Engine
GET	{prefix}/health	liveness
GET	{prefix}/{unit}	live
GET	{prefix}/{unit}/{id}	one live row by id
POST	{prefix}/{unit}	put
PATCH	{prefix}/{unit}/{id}	set (partial body)
DELETE	{prefix}/{unit}/{id}	end
POST	{prefix}/{unit}/{id}/{bond}	tie body {"right": id}
DELETE	{prefix}/{unit}/{id}/{bond}/{tie}	cut
POST	{prefix}/query	body {"q":…} → always pack

listen.prefix in keel.toml is the api prefix (default empty).

Runtime config (keel.toml)

Repo-rooted, negentropy-style. Missing file uses the same defaults:

[listen]
host = "127.0.0.1"
port = 3000
prefix = ""
# prefix = "/api"

[store]
kind = "memory"
# kind = "file"
# path = ".local/keel.sqlite"

[cache]
kind = "memory"
# kind = "none"

let cfg = keel::config::load(".");
let store = cfg.open()?;
let core = bind(graph, store)?;
// listen(core.share(), &cfg.listen.host, cfg.listen.port).await?;

keel-api [ROOT] loads ROOT/keel.toml (default ROOT=.). CLI does not re-express policy keys — change the file.

Local process (sidecar)

# requires sidecar CLI installed
sidecar start --config sidecar.toml
# health: http://127.0.0.1:3000/health
sidecar stop --config sidecar.toml

keel-api is a demo binary (Student/Course selection + store/listen from keel.toml). forge is the staged scenario binary (docs/model/spec.md); keel-gate ships the default credential package (gate!(Actor) + wall).

Operating

runseal :init
runseal :guard    # unit tests + smoke + course + forge scenarios
runseal :smoke    # thin L2
runseal :course   # classic enroll/drop/schedule L2
runseal :forge    # forge slice act 1: data completeness L2
cargo run -p keel-api --locked

Scenario notes: docs/run/scenario.md.

Cold-start verification boundary: docs/run/verify.md.