Xmlang.Cli 0.6.0

xmlang

xmlang is a YAML-based DSL for Experience Models: the sibling dialect to emlang (Event Models as YAML), recording the UX judgments an Event Model deliberately omits — personas, surface composition, field salience, journeys, labels, design tokens — as data, never as geometry. The Experience Model depends on the Event Model strictly one-way, and every reference is lintable.

The canonical specification lives here: xmlang-spec.md; the emlang dialect it depends on is specified as a delta against upstream in emlang-dialect.md. This repository is also the reference implementation: a parser, an Event Model resolution surface, and a linter implementing the spec's full rule set.

The repository also hosts the .NET implementation of emlang itself — xmlang cannot live without it. The emlang here is an opinionated dialect: an Event Model DSL for Vertical Slice Architecture × Decider × Dynamic Consistency Boundaries (see Stance).

• Emlang — the em parser (EmParser, the reference surface xm resolves against) and the line-aware AST, linter and formatter (Emlang.Linting).
• Emlang.Cli — em, the .NET clone of the reference Go CLI (dotnet tool install -g Emlang.Cli). Commands so far: em parse, em lint and em fmt (-w, --keys short|long) with the reference toolchain's rule set and output format, stdin via -, plus version/help.

This repository is the two DSLs and nothing downstream of them. Code generation from a model is an application concern: each app carries its own source generators against its own conventions (kvissig.se has one for its deciders; CritterStackHelpDesk will have one for its Blazor surfaces). Emlang.Generators was extracted to kvissig.se on 2026-09-14 and is no longer published.

The emlang packages version and release independently (tags emlang-v*) from the xmlang packages (tags xmlang-v*).

Stance

Event Modeling draws a system as a timeline of slices. This dialect takes three positions on what a slice is, and the RFCs make them lintable:

The intended domain is B2B SaaS and line-of-business software. Background on the method: Martin Dilger, Understanding Eventsourcing.

The dialect forks the upstream emlang spec v1.0.0 grammar: it adds an s: state element and makes the decider rules the default. Upstream tools do not read dialect files. The positions above are accepted RFCs under rfcs/ (2026-09-14), not yet implemented in src/.

Install

The library (parser + linter, for build-time tools or runtime interpreters):

dotnet add package Xmlang

The CLI (a dotnet global tool named xm):

dotnet tool install -g Xmlang.Cli
xm lint specs/my-game.xm.yaml

xm lint resolves the document's model: Event Model(s) relative to the xm file, prints every finding, and exits non-zero on errors.

Usage (library)

using Emlang;
using Xmlang;

var xm = XmParser.Parse(File.ReadAllText("shop.xm.yaml"));
var em = EmParser.Parse(File.ReadAllText("shop.em.yaml"));
var findings = XmLinter.Lint(xm, em);

Versioning

The Xmlang package minor version tracks the specification version (Xmlang 0.6.x implements spec v0.6); the patch component is free for implementation fixes. The Emlang packages carry their own SemVer (emlang-v* tags) and implement the decider dialect in emlang-dialect.md, forked from upstream emlang spec v1.0.0.

Provenance

Extracted from the proprietary kvissig.se codebase and relicensed under MIT by its copyright holder.

License

MIT