ikigai-layers

Shared spaces between people, their agents and their machines, where who said what is stamped by the host, what may be said is a closed shape, and who may see what is a capability you can read off a file.

Bringing a collaborator into your work usually means one of two bad trades: give them a seat in your tools (and with it everything else in there), or carry messages by hand between two worlds. A layer is the third option: one independent, named space (urn:layer:talk) that the people, the LLM agents acting for them and their automation all read and write through the same doors, under grants that say exactly which layers each one holds and nothing more.

• A layer is configuration, not code. One TOML file picks an access model, names the closed SHACL shapes every write must conform to and the JSON-LD context that is the layer's egress allowlist. A new channel for a new collaboration is a file.
• Attribution is not optional and not forgeable. The door that authenticated the caller mints its principal; the host stamps it (prov:wasAttributedTo), the kernel clock's time (dcterms:created) and the entry's position in the feed (ik:seq) into every entry, and refuses any of the three if a writer sends them.
• Append-only by construction. There is no edit and no delete. A correction is a new entry that ik:supersedes the old one, only ever its own author's.
• Taking work is claiming it. In a task layer, a take is atomic: of two participants taking one offer, exactly one wins, the other is told who did, and a receipt naming the winner is written before either hears back. Reports on an offer are addressed to its offerer, and only its taker can send them.
• Isolation is the default, and enforced. A layer belongs to one collaboration unless its own definition records the decision to share it. A manifest that mounts someone else's layer stops the host from starting and the grant generator from writing.
• Nobody polls. Every layer has a gapless, cursor-resumable feed with a long poll, and one read can wait on all the layers a participant holds.
• An agent's tool list is its grant. Each layer action is its own endpoint declaring its layer's exact capability, so the MCP tools a participant's Claude sees are exactly the layers that participant holds.

The resources

A channel layer binds say, entries, entry, graph and latest; a tuplespace layer binds tuples and receipt; every layer binds its definition, shapes, context and feed. Every answer a participant reads also comes as JSON: see JSON faces.

Endpoint ids are layer-{layer}-{action} (layer-talk-say), so MCP tools are layer-talk-say__sink, layer-tasks-bobby-tuples__delete and so on. Layer names are lowercase [a-z0-9-], at most 24 characters, which keeps the longest tool name inside MCP's 64, and never a Windows device name (nul, con, com1, …), since a layer's name is also a directory; participant short names follow the same rule.

This version builds two access models: channel (append-only entries, one graph per author) and tuplespace (offers taken atomically, reports addressed to their offerer, with receipts). The graph model (each author replaces their own graph) is not built; a definition naming it is refused, never served as something it is not.

Configuration

One directory, the layer host's config home:

<config dir>/
  layers/talk.toml           a layer's definition
  layers/msg.shapes.ttl      the closed shapes it names
  layers/msg.context.jsonld  its egress context
  participants.ttl           who each principal is
  collabs/bobby.toml         a collaboration's manifest
  enrollment.toml            certificate fingerprints (read by the generator only)
  layers.toml                optional: the host's own options (the `match` budget, below)

A layer:

# layers/talk.toml   ->  urn:layer:talk
model   = "channel"
shapes  = "msg.shapes.ttl"       # closed SHACL shapes: what may be written
context = "msg.context.jsonld"   # the egress allowlist
entry_max = "16KiB"              # optional; the default
shared  = ["bobby", "chris"]     # optional: the collaborations that may mount it

A task layer:

# layers/tasks-bobby.toml   ->  urn:layer:tasks-bobby
model     = "tuplespace"
shapes    = "tasks.shapes.ttl"
context   = "tasks.context.jsonld"
addressed = true                 # a tuple with ik:addressedTo is taken only by an addressee
match     = false                # optional; the default: `rd match=` is refused

addressed and match are a tuplespace's options and about a channel's; naming one on the other model is refused, like a misspelled key.

match is off by default. A match= template is the caller's own SPARQL ASK, evaluated against every pending tuple: the store's limits bound a query's size and nesting, and a cross join of triple patterns is a few hundred bytes and shallow, yet costs about 8x more for each pattern added: seconds on one tuple at eight patterns, minutes at ten, and again for every pending tuple (ledger #1327). So on a layer that does not say match = true, rd match= is refused (InvalidArgument on match, naming the option) and the tuples door does not declare match at all; rd without a template, out and take are unchanged. Turn it on only for a layer whose every reader you would hand a thread to.

A template runs within one time budget per host (ikigai-intray 0.1.55's, from ikigai-store; ledger #1362). Its caller is answered with a Timeout at the budget; a template that cannot be stopped at once (oxigraph checks its cancellation only where it touches the data) goes on running and is counted as OVERDUE, and while max_overdue are, every new rd match= on ANY layer of the host is refused at once as Unavailable. The host builds the budget once and every tuplespace layer shares it, so the cap is the host's, not each layer's:

# layers.toml (optional; every key defaults)
[match]
budget_ms   = 2000   # default 5000
max_overdue = 1      # default: a quarter of the machine's cores, at least 1

A template is evaluated under the host's own authority, so a urn:cap:store:budget:<ms> grant a participant holds does not raise it: budget_ms is what every caller gets. On a small machine the default cap can be 1, and then one abandoned template refuses every later one until it ends: size max_overdue (and budget_ms) deliberately before you turn match on. Host::match_budget() says how many are overdue now.

Every node shape must be sh:closed true and the shapes must target at least one class; an entry must be typed with a targeted class and only those (SHACL answers "conforms" for what nothing targets, so the host refuses that first). The context may not use @vocab, @base, @import or a remote context: it is an allowlist.

The participants:

@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix prov: <http://www.w3.org/ns/prov#> .
@prefix ik:   <https://ikigai-rs.dev/ns#> .
<urn:collab:participant:bobby>        a foaf:Person .
<urn:collab:participant:bobby-claude> a prov:SoftwareAgent ; prov:actedOnBehalfOf <urn:collab:participant:bobby> .
<urn:collab:participant:brian>        a foaf:Person .

A participant is urn:collab:participant:{name}, or a machine named the way its door names it, urn:iki:host:{host}:client:<fingerprint>.

A collaboration:

# collabs/bobby.toml   ->  urn:collab:bobby
[[mount]]
layer = "talk"
bobby        = ["read", "feed", "say"]
bobby-claude = ["read", "feed", "say"]
brian        = ["read", "feed", "say"]

Enrollment is generated

ikigai-layers grants <config dir> [--out <dir>] [--check]

writes the door's grants.json (one grant per participant: the union of its verbs over every manifest naming it, plus urn:cap:collab:read:{name} for each) and clients.json (each certificate fingerprint from enrollment.toml, or from a machine's own name, mapped to its grant with principal = the participant's IRI; no default, so a certificate nobody enrolled is refused). ikigai-cli's door re-reads both on every connection, so an edit takes effect without a restart. A configuration that breaks the isolation rule writes nothing.

Writing an entry

$ cat note.ttl
@prefix ik: <https://ikigai-rs.dev/ns#> .
<urn:layer:new> a ik:Message ; ik:body "The tuplespace arc is next." .

$ cat note.ttl | ikigai -c 'sink urn:layer:talk:say'
urn:layer:talk:entry:01m4hhr0z80000000000001

Turtle or JSON-LD, about <urn:layer:new> (or one blank node); JSON-LD nested more than 64 levels deep is refused before it is parsed. What is stored:

<urn:layer:talk:entry:01m4hhr0z80000000000001> a ik:Message ;
    ik:body "The tuplespace arc is next." ;
    prov:wasAttributedTo <urn:collab:participant:brian> ;
    dcterms:created "2026-10-10T00:00:01.000Z"^^xsd:dateTime ;
    ik:seq 1 .

And a follower that was waiting on source urn:layer:talk:feed after=0 wait=50 wakes with

1 2026-10-10T00:00:01.000Z say urn:layer:talk:entry:01m4hhr0z80000000000001 urn:collab:participant:brian

Offering and taking work

A tuple is one subject that its dropper names, under the layer's own IRI and never used there before:

$ cat offer.ttl
@prefix ik: <https://ikigai-rs.dev/ns#> .
@prefix dcterms: <http://purl.org/dc/terms/> .
<urn:layer:tasks-bobby:offer:01m4hhr0z8> a ik:Offer ;
    dcterms:title "Layer vocabulary" ; ik:brief "Add the layer terms." ;
    ik:repository <https://github.com/ikigai-rs/ikigai-core> .

$ cat offer.ttl | ikigai -c 'sink urn:layer:tasks-bobby:tuples'
urn:layer:tasks-bobby:offer:01m4hhr0z8

The host stamps who dropped it, when and its feed position into the tuple, as for an entry. Sending the same tuple again (a retry after a lost reply) is one record, answered the same way; anything else under a used name is a Conflict.

Taking it is the claim:

$ ikigai -c 'delete urn:layer:tasks-bobby:tuples urn:layer:tasks-bobby:offer:01m4hhr0z8'

answers the tuple, and a second taker is refused with a Conflict that names the first. Before the reply, the host commits a receipt: the take as a prov:Activity that prov:used the offer, prov:wasAssociatedWith the taker, ended at a time, numbered in the feed, with the tuple as taken. A taker that lost its reply reads source urn:layer:tasks-bobby:tuples state=taken tuple=<offer>.

Reports (ik:Progress, ik:Release, ik:Handback with ik:evidence) name the offer with ik:offer and are addressed to its offerer with ik:addressedTo. The host admits a report only from the participant whose take of that offer it holds a receipt for, in an addressed layer only when it is addressed to that offer's offerer alone, and there only an addressee can take it. The feed records out and taken events, with the tuple's subject and who did it.

JSON faces

Every answer a participant reads also comes as JSON, so a participant with only an HTTP client and a JSON parser can take part: no RDF parser is needed on its side. Each face is declared in the resource's description (its as argument and outputs), so a door over QUIC, an HTTP front, MCP and the action manifold all offer the same ones.

A face a resource does not offer is refused (invalid-argument on as), never answered in another. One tuple (tuple=) is a graph, so it is refused as application/json, a list's face. In the lists, seq is a JSON number, as in the feed.

A graph is the layer's egress context, PRUNED and compacted: the stored graph is expanded, everything the context does not define is removed (a property, a type, a datatype; a prefix is not a term), and the rest is compacted with that context. The host does this with ikigai-jsonld's prune, in a kernel of its own that no door binds, so no participant can call the pruner. Its shape is fixed:

• one object with exactly two members: @context (the context it was compacted with) and @graph, an ARRAY of node objects in the answer's order (feed order for a list), so one node and many look the same, and none is an empty array;
• in each node, @id is the node's whole IRI, and @type a term of the context (a string for one type, an array for several); every other key is a term of the context, never a full IRI, and a property the context does not define is absent;
• a property with one value is that value, with several an array (a term defined with "@container": "@set" is always an array);
• an IRI value is a string when its term says "@type": "@id", otherwise {"@id": …};
• a typed literal whose term declares its datatype is its LEXICAL STRING: "seq": "3", "created": "2026-10-10T00:00:01.000Z", "bytes": "aGVsbG8=" (base64 text). A datatype no term declares is removed with its value.

The host's stamps always cross, whatever the layer's context names: the host merges its own terms into every layer's context for these faces.

A receipt is a graph of two nodes: the Activity and the tuple as taken. A layer context may define these terms only as the host does (the shipped contexts do, word for word); one that defines one differently, maps one of these IRIs under another name (compaction would prefer it), has a prefix that would shorten the IRIs the host names, or has a scoped @context (the prune reads one set of terms) stops the host at open, naming the term.

use std::sync::Arc;
use futures::executor::block_on;
use ikigai_core::{ArgRef, Capability, Iri, Kernel, Request, SystemClock, Verb};
use serde_json::Value;

# let dir = std::env::temp_dir().join(format!("ikigai-layers-readme-json-{}", std::process::id()));
# let (config, state) = (dir.join("config"), dir.join("state"));
# let _ = std::fs::remove_dir_all(&dir);
# std::fs::create_dir_all(config.join("layers")).unwrap();
# std::fs::create_dir_all(config.join("collabs")).unwrap();
# let write = |path: &str, text: &str| std::fs::write(config.join(path), text).unwrap();
# let prefixes = [
#     "@prefix sh: <http://www.w3.org/ns/shacl#> .",
#     "@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .",
#     "@prefix ik: <https://ikigai-rs.dev/ns#> .",
#     "@prefix prov: <http://www.w3.org/ns/prov#> .",
#     "@prefix dcterms: <http://purl.org/dc/terms/> .",
#     "@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .",
# ].join("\n");
# let stamps = "[ sh:path prov:wasAttributedTo ; sh:nodeKind sh:IRI ] , \
#     [ sh:path dcterms:created ; sh:datatype xsd:dateTime ] , [ sh:path ik:seq ; sh:datatype xsd:integer ]";
# write("layers/msg.shapes.ttl", &format!("{prefixes}\n<urn:example:shape:message> a sh:NodeShape ; \
#     sh:targetClass ik:Message ; sh:closed true ; sh:ignoredProperties ( rdf:type ) ; sh:property \
#     [ sh:path ik:body ; sh:minCount 1 ; sh:datatype xsd:string ] , \
#     [ sh:path dcterms:subject ; sh:nodeKind sh:IRI ] , {stamps} ."));
# write("layers/tasks.shapes.ttl", &format!("{prefixes}\n<urn:example:shape:offer> a sh:NodeShape ; \
#     sh:targetClass ik:Offer ; sh:closed true ; sh:ignoredProperties ( rdf:type ) ; sh:property \
#     [ sh:path dcterms:title ; sh:minCount 1 ; sh:datatype xsd:string ] , {stamps} ."));
# write("layers/msg.context.jsonld",
#     r#"{ "@context": { "ik": "https://ikigai-rs.dev/ns#", "Message": "ik:Message", "body": "ik:body" } }"#);
# write("layers/tasks.context.jsonld", r#"{ "@context": { "ik": "https://ikigai-rs.dev/ns#",
#     "dcterms": "http://purl.org/dc/terms/", "Offer": "ik:Offer", "title": "dcterms:title" } }"#);
# write("layers/talk.toml", "model = \"channel\"\nshapes = \"msg.shapes.ttl\"\ncontext = \"msg.context.jsonld\"\n");
# write("layers/tasks.toml", "model = \"tuplespace\"\nshapes = \"tasks.shapes.ttl\"\ncontext = \"tasks.context.jsonld\"\n");
# write("participants.ttl", "<urn:collab:participant:brian> a <http://xmlns.com/foaf/0.1/Person> .\n");
# write("collabs/team.toml", "[[mount]]\nlayer = \"talk\"\nbrian = [\"read\", \"say\"]\n\n\
#     [[mount]]\nlayer = \"tasks\"\nbrian = [\"read\", \"out\", \"take\"]\n");
let host = ikigai_layers::Host::open(&config, &state).expect("a configuration that checks");
let kernel = Kernel::new(Arc::new(ikigai_layers::space(&host))).with_clock(Arc::new(SystemClock));
// What a door mints for a participant holding these grants.
let brian = Capability::scoped([
    "urn:cap:layer:say:talk", "urn:cap:layer:read:talk",
    "urn:cap:layer:out:tasks", "urn:cap:layer:read:tasks", "urn:cap:layer:take:tasks",
].map(String::from))
.with_principal("urn:collab:participant:brian")
.unwrap();
let call = |verb: Verb, iri: &str, args: &[(&str, &str)]| -> Value {
    let mut request = Request::new(verb, Iri::parse(iri).unwrap());
    for (name, value) in args {
        request = request.with_arg(*name, ArgRef::Inline(value.as_bytes().to_vec()));
    }
    let answer = block_on(kernel.issue(request, &brian)).unwrap();
    serde_json::from_slice(&answer.bytes).unwrap()
};

// say, answered as JSON: the IRI the host named.
let note = "@prefix ik: <https://ikigai-rs.dev/ns#> .\n\
            <urn:layer:new> a ik:Message ; ik:body \"Next: JSON.\" ;\n\
            <http://purl.org/dc/terms/subject> <urn:example:topic> .";
let said = call(Verb::Sink, "urn:layer:talk:say", &[("content", note), ("as", "application/json")]);
let iri = said["@id"].as_str().unwrap().to_string();
assert!(iri.starts_with("urn:layer:talk:entry:"));

// The entries, as JSON-LD: always a top-level @graph array.
let doc = call(Verb::Source, "urn:layer:talk:entries", &[("as", "application/ld+json")]);
let entries = doc["@graph"].as_array().unwrap();
assert_eq!(entries.len(), 1);
let entry = &entries[0];
assert_eq!(entry["@id"], iri.as_str());
assert_eq!(entry["@type"], "Message");
assert_eq!(entry["body"], "Next: JSON.");
assert_eq!(entry["attributedTo"], "urn:collab:participant:brian");
assert_eq!(entry["seq"], "1"); // a lexical string, not a number
assert!(entry["created"].as_str().unwrap().ends_with('Z'));
// The context does not define dcterms:subject, so it did not cross.
assert!(entry.get("subject").is_none());
assert!(!doc.to_string().contains("urn:example:topic"));

// out, answered as JSON; rd's list as JSON; take as JSON-LD.
let offer = "@prefix ik: <https://ikigai-rs.dev/ns#> .\n\
             <urn:layer:tasks:offer:1> a ik:Offer ; <http://purl.org/dc/terms/title> \"JSON faces\" .";
let dropped = call(Verb::Sink, "urn:layer:tasks:tuples", &[("content", offer), ("as", "application/json")]);
assert_eq!(dropped["@id"], "urn:layer:tasks:offer:1");
let pending = call(Verb::Source, "urn:layer:tasks:tuples", &[("as", "application/json")]);
assert_eq!(pending["layer"], "tasks");
assert_eq!(pending["tuples"][0]["seq"], 1); // a list's seq is a number, as in the feed
assert_eq!(pending["tuples"][0]["subject"], "urn:layer:tasks:offer:1");
assert_eq!(pending["tuples"][0]["dropper"], "urn:collab:participant:brian");
assert!(pending["tuples"][0]["created"].is_string());
let taken = call(Verb::Delete, "urn:layer:tasks:tuples",
                 &[("tuple", "urn:layer:tasks:offer:1"), ("as", "application/ld+json")]);
assert_eq!(taken["@graph"][0]["title"], "JSON faces");

// A taker whose reply was lost reads the take back from its receipt: two nodes.
let receipt = call(Verb::Source, "urn:layer:tasks:tuples", &[
    ("state", "taken"), ("tuple", "urn:layer:tasks:offer:1"), ("as", "application/ld+json"),
]);
let nodes = receipt["@graph"].as_array().unwrap();
let activity = nodes.iter().find(|n| n["@type"] == "Activity").unwrap();
assert_eq!(activity["used"], "urn:layer:tasks:offer:1");
assert_eq!(activity["associatedWith"], "urn:collab:participant:brian");
assert_eq!(activity["seq"], "2");
assert!(activity["endedAt"].is_string());
assert!(nodes.iter().any(|n| n["@type"] == "Offer" && n["seq"] == "1"));
# drop(kernel);
# drop(host);
# std::fs::remove_dir_all(&dir).unwrap();

A gateway between kernels

One kernel asks another to resolve a resource and gets the answer back, through layers, with neither resolving into the other and neither adopting the other's wire, cache or security model (ledger #1370). It is configuration: the example in gateway/ is two kernels, plasma and remote, each asking the other.

• An ask layer per asker (gateway-plasma): a tuplespace, addressed = true. The layer is the read boundary (whoever holds read on a layer reads all of it), so an asker's requests and answers are seen by that asker and the resolvers serving it, and by no other asker. A resolver sees every request on the layers it serves: it is the server.
• An event channel per resource owner (gateway-events-plasma): only the owner holds say, so nobody can invalidate another kernel's resources; every kernel that may ask the owner reads it.
• Closed shapes (gateway.shapes.ttl, gateway-events.shapes.ttl) and egress contexts with no @vocab. The terms are layer-local under urn:layers:gateway: (gw:) beside core's ik:verb, ik:mediaType, ik:offer, ik:addressedTo and ik:seq.

The asker is the host's stamp (prov:wasAttributedTo), never a field. The host enforces the protocol: the atomic take gives a request to exactly one resolver; an answer is admitted only from the participant whose take of the request the layer holds a receipt for, addressed to the asker alone, and only the asker can take it.

A request runs under the resolver's authority, never the asker's. No capability crosses a layer. The resolver issues the request into its own kernel under the capability its operator gave it, answers only the verbs its operator allows (by default Source, Exists and Meta, none of which changes anything; a mutating verb is answered denied) and, when its operator sets them, only names under given prefixes. The layer grant says who may ask; the resolver says what asking can do.

The reference participant for an ikigai kernel is ikigai_layers::gateway: an Asker drops a request and waits for its answer with a deadline (withdrawing a request no resolver took in time), and a Resolver with serve, serve_pending and follow takes requests, resolves them and answers. A representation larger than the layer's entry_max (base64 costs a third) is answered as an endpoint failure saying so.

The wire contract a participant carries

Every step is an ordinary request at the layer host, so this is also what an HTTP front for non-ikigai participants (not built yet) must carry: a verb, an IRI and named arguments in; a media type and bytes out; and for an error, its KIND and message and, for missing-argument and invalid-argument, the argument's name, because a participant branches on them (a conflict on a take is a lost race, a not-found is an answer not there yet). The front authenticates the participant and mints its principal, exactly as the ikigai door does; the participant never names itself.

An asker, on its own layer:

A resolver, on each layer it serves:

What crosses, Turtle or JSON-LD under the layer's own context (Source urn:layer:{layer}:context); answers come back as Turtle, or, asked as=application/ld+json, as that context compacted (the reply below as {"@context": …, "@graph": [{"@id": …, "@type": "Reply", "offer": …, "mediaType": "text/plain", "bytes": "aGVsbG8=", "seq": "3", …}]}), which a participant with no RDF parser reads as plain JSON:

{ "@context": { "…": "the layer's context, inline" },
  "@id": "urn:layer:gateway-plasma:request:01m4rjm4zt",
  "@type": "Request",
  "correlation": "01m4rjm4zt",
  "resource": "urn:example:hello",
  "verb": "Source",
  "argument": ["as=text/plain"] }

<urn:layer:gateway-plasma:reply:01m4rjm4zt> a gw:Reply ;
    ik:offer <urn:layer:gateway-plasma:request:01m4rjm4zt> ;
    ik:addressedTo <urn:collab:participant:plasma> ;
    gw:correlation "01m4rjm4zt" ;
    ik:mediaType "text/plain" ;
    gw:bytes "aGVsbG8="^^xsd:base64Binary ;
    prov:wasAttributedTo <urn:collab:participant:remote> ;
    dcterms:created "2026-10-12T18:00:01.000Z"^^xsd:dateTime ;
    ik:seq 3 .

Not built yet, and stated so nothing is inferred from silence: the HTTP front itself; any publication of invalidations from golden-thread cuts (the shape is here, the mapping is the research question); binary arguments (an argument is text; a Sink of bytes is not carried); a per-asker capability on the resolver side (every asker gets the resolver's one); and any cleanup of an answer that arrives after its asker gave up (it stays pending, addressed to the asker).

Hosting it

A host library: a host (ikigai-cli's serve) opens a Host over its configuration and state directories and binds ikigai_layers::space(&host), alone, on a kernel with a clock. State is plain files: each entry is written once to <state>/{layer}/graphs/{author}/{id}.ttl, and each feed is <state>/{layer}/feed.log.

• One host per state directory. The host holds <state>/host.lock exclusively while it lives; a second host over the same directory, in this process or another, is refused with the holder's pid. The operating system releases the lock when the holder exits, however it exits.
• Admission is the host's own call. The host links ikigai-shacl and validates every write itself, so a door binds no urn:shacl:validate: that endpoint declares no capability, and bound in a door it would be offered to every participant. A layer whose shapes the validator cannot compile stops the host at open.
• Who a participant can learn about. urn:layers:participants is the whole host's roster and no generated grant reads it; each participant reads urn:collab:{name}:participants for its own collaborations, under the urn:cap:collab:read:{name} its grant already carries.
• Who a participant is, by its own door's word. urn:layers:me answers the principal the door minted for the caller, so a client never infers its identity from the attribution on records it already holds. It is readable under any generated grant, needs no new token, and lists only the collaborations whose exact tokens the caller holds. A request that names no principal (root names nobody) is refused, never answered with an empty graph.

A tuplespace layer fronts an ikigai-intray space at <state>/{layer}/tuples/, which the host links and calls under its own urn:cap:space:*: participants never hold a space capability, and the space is never bound into the kernel. Intray's take is a rename, which is what makes it atomic. Receipts are <state>/{layer}/receipts/{id}.ttl. Keep the state directory out of any intray root a reactor watches.

License

Licensed under either of MIT or Apache-2.0, at your option.