Nightly snapshot 2026-09-20 (nightly-20260920-b8dd0e0c8)

Development snapshot of develop, not a release. Built 2026-09-20 from b8dd0e0, 1175 commits after v0.8.1 (compare), by this workflow run. Every binary reports nightly-20260920-b8dd0e0c8.

The snapshot is replaced each night and is never the latest release; Homebrew, PyPI, npm and the Windows installer follow the stable line only. The snapshot page explains what it is, how to verify it and what to expect from it; the install guide covers the stable releases.

opensysml-sysml.vsix is the VS Code extension built from the same commit: code --install-extension opensysml-sysml.vsix, with a snapshot's sysml-lsp on your PATH or named by opensysml.server.path.

Verify a download against the signed manifest:

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  --certificate-identity https://github.com/Open-MBEE/OpenSysML/.github/workflows/nightly.yml@refs/heads/develop

Unreleased changes in this snapshot

One line per entry; the full text is under changes/unreleased/ and CHANGELOG.md at this commit.

Added

• The analysis libraries' conformance is measured, per package, by a runtime test.
• A design note on surface parity
• A persistent session in the public Go API.
• Diagram layout is written into the document that declares what holds it, across the workspace.
• RelatedElements traverses requirement derivation and refinement.
• The VS Code diagram is open by default.
• The VS Code diagram moves a declaration when a node is dropped on another with Shift held.
• The VS Code diagram panel opens a document that declares several views intelligently, and can show several of them at once.
• The VS Code diagram panel draws in the pilot visualizer's style, and in colour, on request.
• A due do step against the dispatch due at the same instant is a recorded choice point.
• Document queries read the objects a session holds.
• Document queries report which constraints and requirements hold.
• An exploration runs a behavior on an object nested inside an assembly, named by a path from a declaration.
• -instantiate gives its object to every explored run.
• A service request names the performer of an action or state machine.
• The fUML test models are read and every activity is classified before any is translated.
• The fUML reference implementation's activity tests are provisioned as an oracle for the action executor.
• The fUML test activities referee the action executor.
• A document query over gRPC binds an object the service holds.
• ApplyEdits edits a model of several documents as one atomic batch.
• The Java client wraps every RPC the service offers.
• A design for scaling to very large models
• Documents typeset LaTeX mathematics, inline and displayed.
• The language server runs the behavior a diagram draws.
• The Windows installer now runs a setup wizard.
• A nightly snapshot of develop is published as the prerelease nightly.
• The nightly snapshot ships the VS Code extension.
• sysml-lsp is declared to OpenCode.
• Document queries express requirement coverage gaps.
• The order in which a state's regions are entered, exited and fired across is a recorded choice point.
• A design note on the order of orthogonal regions
• A satellite-network stress workload and its scaling record.
• The architecture self-model now shows the runtime from the inside.
• A fifth runtime-showcase model: a spacecraft downlink.
• A document query reads the state a session's objects are in and the trace their run recorded.
• The trace is a typed record the printer writes from.
• A manual page tells the query kinds apart.
• A continuous model runs by time-stepping.
• A model states its own odds.
• Monte Carlo runs.
• terminate runs in an action.
• terminate ends an occurrence, a state's behavior or the state machine.
• Four graded requirements-traceability examples in the manual.
• A wide table in a PDF lands on landscape pages.
• RelatedColumn(name, relationshipKind, direction, maxDepth, aggregate) projects the elements a relationship reaches from each row.
• A satisfaction asserted by an object's type and found again in a validation scope is reported once.
• The SysML v1 migration writes behaviors that run.
• A send addressed to a parameter, pin or local of the sending action reaches the object it holds.
• perform action x ::> part.action; and exit part.action; run on the part.
• A run resolves its random draws under a policy.
• A «Probability» that names a property is a feature reference.
• Simulation run configurations migrate.
• The tool's results come across, and a harness compares them.
• An object is validated as a whole.
• A worked example of verdict queries.

Changed

• check no longer reports exhaustive where its moves leave a run out.
• The Python, Node, Java and Rust clients moved from clients/ to client/, beside the Go client.
• A completion enabled by a region's entry stays a run-to-completion step of its own; the design that would have drawn its firing inside the entry front is closed without code.
• Diagnostic and Severity moved from internal/core/passes to the leaf package internal/core/diag.
• The PDF document backend sits beside the renderer it drives.
• The refusal of a session object under exploration says what to name instead.
• A check's outcome carries the attributes the performing objects hold.
• An action executed on an object performing it runs that one performance.
• Conversions are driven from internal/core/convert, not from the RDF mapping.
• The conformance mode lives with the diagnostics it grades.
• Atomic file replacement lives with the other file-level primitives.
• Normative library ids are minted in identity itself.
• A symbol's source origin is read off the symbol.
• Quick-fix edits live with the diagnostics that carry them.
• Rename conflict checking lives with the rename edit.
• The fUML referee driver source lives under scripts/fuml-driver/io/opensysml/fuml/.
• The test-suite figures are counted from the tree when the documentation site is built, never committed.
• The RDF exporter no longer carries the engine model forms.
• sysml -help and the manual page list the options by task.
• A mistyped flag prints the error, the synopsis and Run 'sysml -help' for the options.
• %help groups every REPL command under a heading and wraps its description.
• The simple name a qualified name ends in is computed in one place.
• Moved the validation packages to internal/check.
• Moved the document packages to internal/doc.
• Moved the execution packages to internal/exec.
• Moved the frontend packages to internal/frontend.
• Moved the semantic IR packages to internal/ir.
• Moved the semantic packages to internal/semantic.
• Moved the foundation and syntax packages to internal/syntax.
• Moved the translation packages to internal/translate.
• Moved the workspace packages to internal/workspace.
• The notation-text helpers moved from internal/core/lexer to internal/core/source.
• The migration and referee XMI readers now share one parser.
• The conversion between runtime values and the API's protobuf messages is its own package, internal/protoconv.
• Every failing PSSM test is attributed.
• The PSSM referee classifies a guard whose behavior acts on the model as having no translation.
• The Python client is released with the core, from the same v* tag and at the same version.
• Qualified-name rendering and declaration-body lookup each have one home.
• A state's inline do body is interrupted between its statements.
• Runtime and gRPC robustness cases are registered per feature, not in one shared function.
• The runtime no longer imports the parser.
• The runtime selects call overloads through the semantic model, with the argument typing its caller installed.
• Sorted map keys come from the standard library.
• The declared errata overlay now covers the bundled standard library.
• The built binaries are about a quarter smaller.
• A symbol's declaring element is read through one method.
• Test-support packages live under tests/.
• The OMG corpus gates and the RDF round-trip ratchet move to tests/corpus.
• The gRPC conformance suite and the external-package tests move under tests/.
• The parser's black-box suites move to tests/parser.
• The repository root gains a tests/ tree for black-box test code and fixtures.
• The counting gates and the remaining unreleased programs live in the tools module.
• The development tools are a nested Go module, tools/.
• The errata overlay is split from the registry.
• The referees live in the tools module.
• PDF headings and captions stay with what they introduce.
• A workspace copy of a library file rooted at the library's packages is the library, as it is for the RDF mapping.
• A file opened under a bundled library's own name no longer removes that library from the workspace when it is closed.
• The XMI element walker the PSSM referee reads its suite with is now its own package, internal/xmi

Fixed

• Several completion transitions out of one state are one choice.
• A diagram panel left open across an extension update restored blank.
• explore varies the first run's choice points earliest first.
• A fork may enter orthogonal regions that have no initial state.
• A transition into a history pseudostate restores the configuration it is leaving.
• The PSSM referee's translation no longer folds an initial transition's effect into the entry action of the state or region it starts.
• A join runs the effect of every transition into it.
• A join's segments fire with their own trigger's arguments, and a refused replay undoes them all.
• A junction with several enabled outgoing branches draws one of them as a choice point.
• An edit no longer re-derives every wildcard import in the workspace.
• Completion keeps its name table across edits.
• Semantic tokens index the text they were computed from.
• SysML v1 migration no longer copies opaque expressions whose cast multiplicity bounds or body-local connection/flow endpoints name members the model lacks, and treats declared connector-end names as in scope within their connector bodies.
• A body inside a nested definition no longer reaches the enclosing definition's features by their bare names.
• The nightly snapshot signs again.
• The nightly snapshot's release notes no longer break mid-sentence: GitHub renders a release body with hard line breaks, so each paragraph is written as one line.
• The nightly snapshot no longer falls back past the commit it was last built from when develop's head is red: the walk for the newest green commit ends at the published snapshot, so a night with nothing newer green leaves the previous snapshot standing instead of publishing an older commit — or failing on one that predates scripts/build-release-artifacts.sh, which is now skipped.
• The pilot corpus downloader refuses to report success over an empty corpus.
• The PSSM referee's translation carries the values a test's constructor writes.
• A redefinition is masked along an alias path too.
• A segment leaving a junction or choice declared inside a composite state runs its effect after that state's entry.
• The npm platform packages and the nightly pipeline build statically linked binaries too.
• A document binding may name a nested usage in dot notation.
• A verification case is matched to a requirement by the declaration it names.
• The pandoc PDF engine no longer receives a document-css variable.
• A wide table in a PDF document stays within the page.
• A transition from a substate into the composite state enclosing it no longer restarts that state's default substate: the composite is already active, so it is not re-entered, and the body the substate left completes — a composite with no other region completes and its completion transition fires, a parallel owner waits for its other regions.
• A parallel region stood for by a stateless state needs no initial.
• Every witness check writes replays.
• XMI metadata attributes on stereotype applications are no longer emitted as stereotype tags.

Performance

• A workspace keeps its semantic model between edits and invalidates it per document.
• Resolving a name through a scope no longer rescans every anonymous member of that scope for implicit parameters.
• Checking n satisfy assertions no longer walks the model n times for verification cases.