What changed
What each ESS release is worth to somebody using it: what became possible, how much it matters, and where to read the rest, newest release first. The changelog is the complete record at the level each change was made; this page is the short one.
This page is generated from the change records kept in the repository. A release with no entry here added nothing somebody using ESS would act on.
0.84.0 — 2026-11-03
Generated servers refuse what their OpenAPI refuses, and generated UIs call their binding's routes
capability · significant impact · release post · release notes
Generated Rust servers refuse a malformed Timestamp and an undeclared JSON member at decode, and the Go server an undeclared top-level member. Authored success acts assert no error. Denied-grant scenarios reach ranked views and every ungranted actor. Generated UIs call their binding's routes.
0.83.0 — 2026-11-02
Optional list appends, binding refusals that check event identities, and refusals that tell states apart
capability · notable impact · release post · release notes
The interpreted target appends null for an absent optional list element. Binding refusal scenarios compare trigger event identities. A row-set guard beside named rows is witnessed on every refusal order. No-view input refusals read the record back through sends that tell its state apart.
0.82.0 — 2026-11-01
Binding scenarios that check event identities, refusals that probe the record, and validation that names the file
capability · notable impact · release post · release notes
Synthesized binding scenarios compare the trigger event's identity fields with the instance or row they act on. The arranged half of a refusal without an identity view probes the record through the command. ess specify validate names the file a refusal was read from in a specification of several files.
0.81.0 — 2026-11-01
Nullable Binary64 fields in generated types, name aliases in the schema, and synthesis that follows bindings
capability · notable impact · release post · release notes
ess generate types realizes an optional, nullable Binary64 field and refuses a responseless command's response root by name. The schema admits the id: and component: name aliases. Synthesis follows bindings that rewrite a related row, sends refusals beside external branches to a present related row, and picks wrong-state rows with known stored guards.
0.80.0 — 2026-11-01
HTTP-bound inputs and short names in generated types, and input-type rules in Entity Runtime
capability · notable impact · release post · release notes
ess generate types takes --http, so each command input is the request body its bound OpenAPI document publishes, and --names short combines with --all-commands and --all-views. Entity Runtime lowering keeps an unstored input type's invariants and prefix or refuses them by name. Synthesis decides an identity guard on the row it arranges.
0.79.0 — 2026-11-01
Nested-member claims, Binary64 in conformance suites, and typed authored inputs
capability · notable impact · release post · release notes
From ess-scenario/6 a claim may name a nested member by its dotted path, and an authored literal input its type refuses is refused at any depth. Suites /62 and /63 carry a response member path and a finite Binary64, compared by IEEE equality in Rust, Go and TypeScript. Synthesis refutes an inequality against an example.
0.78.0 — 2026-10-31
Structured input examples, rows a deployment provides, and lifecycle summaries
capability · notable impact · release post · release notes
From ess/33 a struct, map or Json input may carry an example that synthesis sends as written. An entity may declare that the deployment provides its rows; suites resolve such a row as an entity fixture and the interpreted target creates it. Transitions and states may carry a summary.
0.77.0 — 2026-10-29
HTTP bindings group alike outcomes, OpenAPI import widens, and validate refuses unreachable branches
capability · notable impact · release post · release notes
HTTP routes group alike outcomes and declare own refusals, empty bodies and arrays. OpenAPI import admits open objects; integer formats keep native width. Types keep declared field order and box only recursion. Response fields may share input names. Validate refuses a branch an earlier refusal hides; mutate scores disjoint precedence swaps equivalent.
0.76.0 — 2026-10-29
Schemas publish entity, Binary64, length and distinct invariants, and composition compares events and constraints
capability · notable impact · release notes
Schemas carry entity invariants and publish Binary64 bounds, text lengths and distinct lists as keywords. Defined / not defined branches are exhaustive without a default. ess-composition/5 compares events, commands, constraints and variant attributes. HTTP bindings name operation ids and servers.
0.75.0 — 2026-10-28
A seed says it does not serve a set move's filter, and the workspace compiles on rust 1.85
capability · notable impact · release notes
A set-move refusal names the selected seed rows that synthesis does not apply and points to an authored scenario. Every refusal a set-move-only state causes names that state. A seeded caller-model scenario notes the swapped-caller run it skips. The workspace compiles on its declared rust-version 1.85, and CI checks it.
0.74.0 — 2026-10-28
Synthesis seeds work on caller models, and a binding tries every publisher of its trigger
capability · notable impact · release notes
A synthesis seed is admitted for a model whose actors declare caller attributes, and the seed row gives the seeded run its caller. A binding is witnessed through any branch that publishes its trigger, including one that publishes per changed row. A refusal names a state that only a set move reaches.
0.73.0 — 2026-10-28
Set-effect bindings, row sets, predicate refusal policies and affects rows past predicates get their scenarios
capability · notable impact · release notes
Synthesis arranges the rows a binding into a per-row set effect needs, keeps a row set followable until a step sets its binding off, witnesses a predicate refusal policy through an arranged row, and arranges an affects row past a creator's predicate guard. A caller model keeps its binding refusal scenarios.
0.72.0 — 2026-10-27
Bindings past related and set guards, and fresh-input disclosure follow-ups, get their scenarios
capability · notable impact · release notes
Synthesis now arranges the related row or the selected rows a binding's invoked command reads through a when_related: guard, where the command updates the trigger's row, chooses its branch by a set guard, or shares the trigger's guard. A one-time response's follow-up whose set effect is pinned to a fresh input composes after the disclosure.
0.71.0 — 2026-10-27
Set updates, affects rows and converted binding inputs get the scenarios synthesis used to refuse
capability · notable impact · release notes
Synthesis now arranges the rows of a set update whose creator copies from, or refuses a missing, related row, and rows the update changes where both write one input. affects: rows are arranged past an emitting not-found branch, and a binding input filled across a plain newtype conversion arranges its related row.
0.70.0 — 2026-10-26
Named rows beside a row set, state wire spellings, and replays that no longer stop with InvalidReplay
capability · notable impact · release post · release notes
Format ess/32 lets one command guard on rows its input names beside a row-set guard, a struct declare fields: [] and a lifecycle state declare its wire spelling. A view may publish a Decimal. ess verify conform synthesize no longer stops with InvalidReplay at ess/26 and later.
0.69.2 — 2026-10-25
An external branch that copies an optional input keeps naming the row its arrangement created
capability · notable impact · release notes
The outcome scenario of an external branch that copies an Optional input, on a command guarded by when_related over the row its input names, ran the branch once more with the Optional left out and named an identity no step created, so it failed every conforming target. Its further runs now name the arranged row, as its plain sibling's already did.
0.69.1 — 2026-10-25
Synthesis takes the time it took in 0.68.0 again where related rows reach their state through a guarded move
capability · notable impact · release notes
0.69.0 arranged the rows a creating branch leaves once per arrangement that asked, so a specification whose related rows reach their state through a move with a stored-field guard synthesized for more than 13 minutes. Those rows are now made once per synthesis, the time is back at 0.68.0's, and the synthesized suites keep the scenarios 0.69.0 added.
0.69.0 — 2026-10-24
Lists can be filled or appended to, absent members sent as null, and ess generate types writes body types
capability · notable impact · release notes
Format ess/31 lets a sets: entry store [] or append an input element to a stored list, a List input carry an example:, and a field's presence: be omitted_or_null. ess generate types generates a command's input and response and a view's row. Binding scenarios act on the row their setup arranged, or are refused as ESS-SYNTH-010.
0.68.0 — 2026-10-22
A reference every writer checks needs no missing-row branch, and a view filter can compare with now
capability · notable impact · release notes
Format ess/30 drops the exists: false branch on a reference every writer checks and nothing deletes. A view's filter: may compare a Timestamp with now, a selector may write coalesce(field, d), a set effect's where: may read state, a narrowed external: race may compensate, and a scenario may pin a generated value.
0.67.0 — 2026-10-21
A guard says what an absent value compares as, and an external branch can be narrowed to some rows
capability · notable impact · release notes
Format ess/29 lets a guard write coalesce(x, d) on the left of a comparison, so a guard over an Optional decides every record, and lets external: carry when_subject:. A one-time read cell names its reader (suite ess-conformance/56). Synthesis witnesses more ranked heads and connective children, and many row-set selectors take seconds.
0.66.0 — 2026-10-20
A generated Go or TypeScript runner shows an unsupported scenario as skipped, and the run still fails
capability · notable impact · release notes
Under report format 2 the generated Go and TypeScript runners end an unsupported required scenario as a skipped subtest or case carrying the target's reason, not a failed assertion. The run still fails once, with one message naming how many required scenarios were unsupported; the report is unchanged.
0.65.0 — 2026-10-20
Synthesis arranges the rows binding, row-set and one-time disclosure scenarios read
capability · notable impact · release notes
Binding scenarios arrange the rows a per-row event, a refusal policy or a stored target names; row-set guards are witnessed beside bindings; affects: rows are arranged behind a missing-row guard; and one-time disclosure cells reach caller, unknown-instance and wrong-state branches the way the ordinary suite does.
0.64.0 — 2026-10-20
A view and a guard read the row a reference names
capability · notable impact · release notes
Format ess/28 lets a view field and a view filter read the row a reference of the source names, one hop, as it is when the view is read; a value read a referenced row's lifecycle state; a branch require several related rows at once; and a guard refuse a list of references that names a missing row. Suite ess-conformance/54 witnesses each navigated view.
0.63.0 — 2026-10-19
A value can be computed by a typed expression, and every guard answers in one precedence order
capability · notable impact · release post · release notes
Format ess/27 computes a value from an expression in sets:, payloads and view fields, reads digest functions in guards, and answers a command's guards in one precedence order, admitting the guard pairs that order settles. ess verify conform diff compares two suites, and a suite states the event catalog once.
0.62.0 — 2026-10-16
A suite holds a command at a fixed now, so a guard on a time boundary is tested exactly there
capability · notable impact · release notes
A conformance suite can hold the instant a target reads as now for one command, and synthesis adds a scenario on each now boundary a command decides by. Format ess/26 holds an external refusal beside an existing row to leave it unchanged. Generated Rust decoders enforce a newtype's alphabet and length; the Go and TypeScript explorers draw timestamps.
0.61.0 — 2026-10-15
Concurrent histories record each call's input and events, and check-history holds them
capability · notable impact · release notes
ess-history/3 records each operation's input and published events, and check-history holds a target to both. Concurrent exploration arranges external: causes and replays a failing seed alone. Synthesis arranges period-bounded views, Rust types take raw JSON values, and the one-time response guide counts disclosure cells.
0.60.0 — 2026-10-14
A composition states which component plays another's role, and which command implements or gates it
capability · notable impact · release notes
ess-composition/4 adds roles:: one imported component plays another's, and each local command implements or gates a contract command, checked for input drift by ess specify compose (#525).
Source format ess/25, and an HTTP binding that generates Rust and Go servers
capability · significant impact · release notes
ess/25 adds create-or-update selection by stored fields, trimmed text guards, one event per changed row and refusals ahead of held state. ess-http/1 binds commands and views to HTTP; ess generate projects it to OpenAPI and emits Rust and Go servers. ess-composition/4 adds roles.
Commands and views bind to HTTP routes, and mutation testing covers more of a model
capability · notable impact · release notes
ess-http/1 binds commands and views to HTTP routes, projected into OpenAPI by --http (#493). mutate covers when_subject:/when_related: guards and authored scenarios (#515). Go synthesis builds when bounded contexts reference each other in a loop.
HTTP bindings declare encodings, statuses, headers and redirects, and synthesis writes Rust and Go servers
capability · significant impact · release notes
An ess-http/1 route declares its request encoding, each outcome's status, body, headers and redirect, and the standard refusals. --http projects them into OpenAPI, and ess generate synthesize --target rust or go writes a server that serves the binding (#493).
Source format ess/25 selects an upsert's update by the stored row and adds per-row events and default view rows
capability · significant impact · release notes
ess/25 lets a create-or-update command pick its update with when_subject: (#530), publish an event per changed row, answer an external: refusal before the row is read, compare trimmed: text, and give a view an absent: row. ess-diff/19 classifies the view change.
0.59.0 — 2026-10-11
An authored act states the caller its command is sent as, and synthesis fixes two guard cases
capability · notable impact · release post · release notes
ess-scenario/5 lets an act state its caller under caller:, so a command that records {caller: …} runs from an authored scenario. Synthesis decides a related guard on a captured struct key (#521) and writes stored-field guard scenarios no view observes (#496).
An authored scenario states the caller its command is sent as
capability · notable impact · release post · release notes
ess-scenario/5 adds caller: to an authored act, so a command that records caller attributes runs from an authored scenario on every target. Synthesis covers when_subject: commands whose guarded field no view observes, and picks a related row against the subject's real key.
0.58.0 — 2026-10-10
A struct or a command response may ignore undeclared fields, and generation, verify diff and runners follow
capability · notable impact · release notes
ess/24 lets a kind: struct type or a command's response declare undeclared_fields: ignored, admitting fields it does not declare. ess generate writes open objects there, ess verify diff classifies opening and closing, and runners admit an undeclared key at exactly those objects. Authored scenarios are judged by the command's precedence plan.
0.57.0 — 2026-10-09
CLI bindings may omit globals, verify diff flags caller-breaking changes, runners check constrained responses
capability · notable impact · release notes
ess-cli/2 lets a CLI binding omit its config and output globals. ess verify diff classifies added and removed domains and rates changes that refuse an existing caller as breaking. Runners check responses of constrained String newtypes. Route-escaping wire names and always-true refusals are refused, and synthesis covers more guards.
0.56.0 — 2026-10-07
A held-state branch must be declared before an overlapping accepting or external branch
breaking · notable impact · release notes
Validation refuses an accepting when: or external: branch declared before a branch the held state selects when one request can satisfy both guards (ESS-COMMAND-004, naming both branches). Every consumer then answers alike. To fix a refused specification, declare the held-state branch first.
Committed output records carry no machine path, and generated Rust types stop forcing arbitrary precision
capability · notable impact · release notes
A settled .ess-output/state.json no longer records the output's absolute path, device or inode, and regeneration refuses an edited owned file. Generated Rust types turn on arbitrary precision only where they hold JSON numbers. Entity Runtime lowers alphabets and text counts, and concurrent generation under a shared directory no longer refuses as busy.
0.55.0 — 2026-10-06
CLI results carry Json, and an optional generated value reads a port
capability · notable impact · release post · release notes
A CLI result field may be typed Json and is written as JSON rather than JSON text, so a caller parses an answer once. A {generated: true} value of type Optional<T> is now supplied by the implementation through a generator port in generated Rust and Go, instead of always being absent; a context that implements the port must add the method.
0.54.0 — 2026-10-06
Counted event claims, generate --check and validation completeness
capability · notable impact · release notes
Suites ess-conformance/44 and /45 match repeated event claims as a set in the Rust, Go and TypeScript runners. ess generate --check reports drift without writing, ess specify validate reports completeness, ess specify formats lists every format, and a CLI binding takes a trailing argument list. A membership operand naming a parameter is refused.
Source format ess/23, re-keyed records, bulk deletes and enum attributes
capability · significant impact · release notes
ess/23 lets an update re-key its record, a value read the state held before the outcome, deletes: remove every row a filter selects, an affects: entry write one record per list element and an enum declare typed variant attributes. Synthesis witnesses state predicates, struct-identity selectors and row sets beside an addressed record.
0.53.0 — 2026-10-05
Experimental protocol specifications and instant-ordered timestamps
capability · notable impact · release notes
Experimental ess-protospec/1 models communicating peers, bounded channels, timers and safety properties; ess verify protocol simulates, replays and explores it. Conformance runners in Rust, Go and TypeScript now order RFC 3339 instants by instant, not by text.
Source format ess/22, row sets and calendar windows
capability · significant impact · release notes
ess/22 adds fact operands, constant offsets, instant comparison, UTF-8 byte length, distinct list members, typed text operands, row sets with filtered related reads, calendar windows at a fixed offset, binding payload conditions and conditional aggregate measures, each checked by synthesized conformance scenarios in the Rust, Go and TypeScript runners.
0.52.0 — 2026-10-03
Event publishers, recursive Rust contracts and consumer fixes
capability · notable impact · release notes
ESS adds declared event transports and typed Rust/Go publishers with native timestamps, positional names and constant constructors. Optional recursive Rust types, generated Go behavior, typed view parameters, UI filters and integer bounds complete the update. Breaking interfaces are documented in the release notes.
0.51.0 — 2026-10-01
Committed generated output regenerates in another checkout
capability · notable impact · release post · release notes
Generated output committed with its .ess-output regenerates in a clone, a second worktree or CI when its owned files still have their recorded bytes, and an unchanged regeneration leaves state.json byte-identical; a state carried without matching files refuses, lists them and prints the steps to re-enroll with ess generate output adopt.
Generated Rust servers select a branch by whether the record exists
capability · notable impact · release post · release notes
A generated Rust server looks the input identity up in the storage port before dispatch, so an existing_instance: refusal beside a creation and a creating unknown_instance: branch beside an update are generated instead of owed; a command whose lookup would not match its creations stays an obligation, and Go, Web and Clap still refuse both forms by name.
0.50.0 — 2026-10-01
Synthesis witnesses an aggregate over rows a when_related-guarded command creates
capability · notable impact · release post · release notes
An aggregate view whose creating command has a when_related guard gets its <view>/aggregate scenario instead of ESS-SYNTH-017: each row's related row is arranged, owner-linked guard inputs name an arranged owner, and a group key read from a related row's owner link holds one owner per value.
0.49.0 — 2026-10-01
Generated servers enforce actor grants
breaking · significant impact · release post · release notes
In a specification that declares actors, generated Rust and Go servers take the authenticated caller and answer 403 not granted before a command runs for a caller the specification does not grant it; served suites witness the refusal. Existing callers of dispatch, handle and serve must pass the caller.
A when_related guard reads the related row's lifecycle state
capability · notable impact · release post · release notes
ess/20 lets a when_related predicate read the related row's held lifecycle state as state, and synthesis arranges a related row of an entity already being arranged one level deep; earlier formats refuse the path and keep their suites.
Synthesis witnesses related copies, owner-linked guards and overlapping branches
capability · notable impact · release post · release notes
Synthesis now witnesses aggregate keys and values copied from a related row, when_related over an owns via field, a fresh caller-supplied identity under swapped callers, and a when: beside a when_subject:; ess verify diff leaves no residual for a one-sided declaration.
0.48.0 — 2026-09-30
An outside runner's results become a conformance report
capability · notable impact · release post · release notes
ess verify conform report turns a runner's per-scenario results into an ess-conformance-report/2 whose producer profile says the results were supplied and ESS executed nothing; aep 0.66.0 records it as evidence.
A served 501 says whether the effect was committed
capability · notable impact · release post · release notes
Every served 501 carries committed: false for an unmet obligation, true when the command took effect and delivering what it published failed. Rust shells gain Refused::Undelivered.
ess ui test runs UI tests by node path
capability · notable impact · release post · release notes
ess ui test runs ess-ui-test/1 tests, which select nodes by their document path, headless against the terminal renderer, and writes a Playwright spec for the generated React project from the same file.
0.47.0 — 2026-09-30
ess-ui/1 UI documents load, check and render
capability · notable impact · release post · release notes
ess-ui/1 describes an application's pages, state and live channels without naming a renderer. ess ui check reports findings by node path, ess ui run --tui runs a document in the terminal, ess generate ui --target react writes a React project, and ess ui docs renders the format reference from its schema.
Generated servers answer with what a command published
capability · notable impact · release post · release notes
The generated Rust and Go servers list the events a command published in its answer, keep request headers, and name and encode every system event. Delivery is tracked per binding, so an undeliverable event no longer blocks later requests, and 501 is declared for a committed command whose delivery failed.
0.46.1 — 2026-09-30
ess verify diff classifies error payload sources and three outcome flags
capability · notable impact · release notes
ess verify diff reports an outcome's error payload: sources declared, dropped or replaced, and a moved accepts: nothing, returns: or caller-decided refusal, as their own changes instead of one unclassified-changed. The new kinds need ess-diff/12; a delta without them keeps its format and bytes.
0.46.0 — 2026-09-30
The Rust target generates what the specification fully determines
capability · significant impact · release notes
ess generate synthesize --target rust generates the command behaviours, view queries and invariant checks the specification fully determines, over storage and context ports you provide. Actor grants arrive as data, the server gains a transport-free handle, --layout crate writes one crate, and ess/19 gives an error's fields their sources.
0.45.0 — 2026-09-29
The Go, web and clap synthesis targets represent Json
capability · significant impact · release notes
ess generate synthesize --target go, web and clap carry Json as rust already does: object members keep their order and numbers their spelling, and a clap flag takes one JSON document. No code target refuses a model for using Json any more, and a model without it synthesizes the same bytes as before.
0.44.0 — 2026-09-29
The Rust synthesis target represents Json, and the public docs are rebuilt
capability · significant impact · release notes
ess generate synthesize --target rust carries Json as the types crate's json::Value, unchanged on the wire. The public docs gain generated CLI and diagnostics references, Start here tutorials a test runs against the built binary, task-sized guides and a what-changed page.
0.43.0 — 2026-09-29
Instance references inside structured values, one refusal precedence and unstated external answers refused
capability · significant impact · release post · release notes
{$instance} works inside lists, maps, structs and unions (suites ess-conformance/32 and /33); acts claiming an unstated external answer are refused ESS-AUTHOR-037. An input refusal may sit beside held-state branches under one precedence order the explorer follows; synthesis meets nested input invariants and witnesses absent fields and stored maps.
0.42.0 — 2026-09-29
Link-field guards, overlap precedence, counter limits and unkillable mutants scored apart
capability · significant impact · release post · release notes
Synthesis witnesses a guard comparing a link field with an input and a stored counter at its limit; the first declared of overlapping accepting branches answers; a relation may ride on the identity. ess-diff/11 names newtype prefix changes, and mutation report and manifest /3 score unkillable mutants apart from survivors.
0.41.0 — 2026-09-29
State-scoped refusals, guards over a related row, delivery context, and a synthesis and mutation defect batch
capability · significant impact · release post · release notes
ess/18 adds state-scoped refusals, state in a when_subject predicate, guards over a related row (when_related:) and a binding's delivery context. Synthesis now witnesses map inputs, identity and link view filters, every creating command and the record a refusal needs; mutation scores gained refusals apart from survivors.
0.40.0 — 2026-09-28
Generated Go and TypeScript runtimes run every suite, and reader-side composition checks
capability · significant impact · release post · release notes
The generated Go and TypeScript runtimes run suites ess-conformance/22 to /27 with the Rust runner's verdicts, where 0.38.0 refused them. ess-composition/3 adds reader: true, admitting the widenings a consumer may read. Duplicate names are refused once, and the schema publishes name charsets.
0.39.0 — 2026-09-28
Concurrent histories checked against the model, and direct library returns
capability · significant impact · release post · release notes
ess verify conform check-history checks an ess-history/1 run of several clients for linearizability against the interpreted model and holds each view to its declared consistency; the Go and TypeScript explorers record concurrent histories and inject declared faults. Source format ess/17 adds returns: true, checked as a typed direct response.
0.38.0 — 2026-09-28
Set effects, caller values, existence-selected outcomes, bounded retries and paged views
capability · significant impact · release post · release notes
Source format ess/16 adds literal fallbacks, defined() over optional aggregates, bodiless requests, related-record values, now in guards, create-or-update outcomes, caller attributes, bounded retries, view paging and outcomes over every record a filter selects. ess-composition/2 checks consumer types.
0.37.0 — 2026-09-27
Outcome shapes, subject guards over the input, new value types and a pinned toolchain
capability · significant impact · release post · release notes
Source format ess/15 adds outcome shapes (deletes:, into:, unknown_instance:, accepts: nothing, preconditions:), input. in subject guards, case-insensitive text, optional aggregates, prefix:, Json and field presence:. Synthesis kills more mutants; ess can run a pinned release.
0.36.0 — 2026-09-27
Payload and sets values read the subject, increment, fall back and nest
capability · significant impact · release post · release notes
Source format ess/14 adds {subject: <field>}, {increment: <n>}, {input: <field>, else: {generated: true}}, nested struct mappings and {generated: true} in sets:. Decimal literals are admitted in every format; subject.<field> as text is refused. Older readers refuse ess/14.
0.35.0 — 2026-09-26
Typed fixture values resolved before a scenario starts
capability · significant impact · release notes
Source format ess/13 adds fixture_inputs: and ess-scenario/3 adds fixtures: with {$fixture: name} references, compiled to ess-conformance/18/19. Rust, Go and TypeScript resolve and type-check the values from an independent provider before the scenario starts. Older readers refuse the new formats; fixture-free models and suites keep their bytes.
0.34.0 — 2026-09-26
String operators, subject guards, aggregate views and outcome groups, and a mutation audit
capability · significant impact · release notes
Source formats ess/8–ess/12 add starts_with/ends_with/contains, when_subject: {predicate: …}, aggregate views with group_by:, alphabet: and input example:, and outcome_groups:. ess verify conform mutate audits a suite with specification mutants. Older readers refuse each new format; models that use none keep their bytes.
0.33.0 — 2026-09-26
A scan records only that a Secret value exists, and a bound workload can acknowledge foreign containers
capability · significant impact · release post · release notes
A Kubernetes scan writes infra-observation/3 and infra-ir/3, recording each Secret key as {"present": true} instead of a digest that confirms a guessed value; infra-drift/3 no longer reports a rotated Secret. ess-observed-bindings/2 acknowledges a mesh proxy or vendor agent by name and reason. Breaking: older readers refuse each new version.
0.32.0 — 2026-09-25
OpenAPI 3.0 imports, and a bound workload's unbound sidecars are violations
capability · significant impact · release notes
ess infra import openapi reads OpenAPI 3.0 by rewriting each schema to its 3.1 form, refusing a construct with no faithful one. ess verify bindings reports OBS-BIND-008 for a container or native sidecar in a bound workload that no binding names. Synthesize orders Timestamp values by the instant they name.
0.31.0 — 2026-09-25
A service contract lowers to Entity Runtime definitions
capability · significant impact · release notes
ess-service-contract extracts an admitted component's service contract, and ess-entity-runtime lowers it into validated Entity Runtime 0.23.0 definitions and typed host binding obligations, refusing what it cannot express by name. Breaking: ess skill and the in-repository plugin are removed; the plugin ships from beyond10x/agentplugins.
0.30.0 — 2026-09-23
ESS ships its own agent plugin, and the binary prints its skills
capability · significant impact · release post · release notes
The ESS agent plugin (ess@ess) now ships from this repository at the binary's version, with skills for writing, retrofitting and conformance-testing a specification. ess skill prints the same skills from the binary, and the release gate refuses a plugin version that differs from the workspace.
0.29.0 — 2026-09-22
Verify retries against their original command results
capability · significant impact · release notes
Source ess/7 declares silent retries of original command results and finite state refusals. Conformance suites 12/13 compare actual retained responses and complete subjects in Rust and Go; unsupported runners refuse. Native APIs preserve typed results, and diff/6 records the new semantics.
0.28.0 — 2026-09-21
Conformance observes history and independently arranged failures
capability · significant impact · release notes
Source format ess/6 models input eligibility for external failures and enum subject history. Suite formats 10/11 compare actual before-and-after subject values and assert silent success. Rust, Go and TypeScript runners reject changed, missing or duplicate subjects; older formats refuse the new vocabulary.
0.27.0 — 2026-09-20
An enum variant carries its own wire spelling
capability · significant impact · release post · release notes
A variant is authored as a bare name or as a mapping that also carries wire, display, summary and code, so a variant whose wire form is not derivable from its name can be declared at all. Specification format ess/5; delta format ess-diff/5 adds three TypeChange cases, so a moved spelling no longer returns an empty delta.
0.26.0 — 2026-09-17
A branch may say the field it owns holds nothing
capability · significant impact · release notes
sets: {field: {cleared: true}} states absence. Before it, a branch either left the field alone, wrote a literal that synthesis dropped, or wrote an empty string, which is a different reading. The field's type must be Optional<...> and the source must be an entity; an event payload is refused because an undetermined field is not the outcome's to set.
0.25.0 — 2026-09-16
An author names the identifier a code emitter spells a declaration as
capability · significant impact · release notes
naming: { code: ... } settles a collision the emitter cannot: a target without dotted type names flattens X.State and an authored view XState to one identifier. Only code emitters read it, so wire names, document schemas and qualified names are untouched and setting one cannot break a deployed consumer. The source format stays ess/4.
0.24.0 — 2026-09-12
A component declares its settings, and the runtime slots are derived from them
capability · significant impact · release notes
settings: states each of a component's configuration inputs once, typed from the specification's own types:. ess specify runtime compile derives the ess-runtime/1 config and secret slots from it, and refuses a hand-authored slot or two settings binding one environment variable twice. Absence is stated with Optional<...> and nothing else.
0.23.0 — 2026-09-11
A branch can turn on the state a subject is already in
capability · significant impact · release notes
when_subject_state in ess/3 combines a declared held lifecycle state with input guards, so equal input applied to two different existing states is distinguished. ess/4 declares error wire names without merging semantic identities and fills emitted event payloads from typed command response fields. New deltas use ess-diff/3 and ess-diff/4.
0.22.0 — 2026-09-10
A binding can declare one delivery attempt and no redelivery
capability · significant impact · release notes
delivery: at_most_once states that a binding is tried once. Loss stays possible and no idempotency obligation is imposed on the handler. OpenAPI requires Idempotency-Key only for at_least_once commands, conformance records BindingGap::DeliverySingleAttempt instead of synthesizing a redelivery, and the format stays ess/1.
0.21.0 — 2026-09-09
A conformance suite records what it covers, and what it left out
capability · significant impact · release post · release notes
Opt-in ess-conformance/5 records selected generated and authored coverage, omitted scenarios, source identities and every refusal occurrence. Report 2 then distinguishes complete passing conformance from empty, unknown or incomplete coverage — a pass over nothing and a pass over everything stop reading the same.
0.20.0 — 2026-09-06
A specification can declare a finite floating-point field
capability · significant impact · release notes
Authored ess/2 adds Binary64 fields, distinct from integer and decimal values. Reference, Rust and Go preserve signed zero, subnormals and nearest-even rounding; two typed operands use IEEE equality. Synthesis and conformance refuse unsupported Binary64 before publication rather than emitting a target that would disagree.
0.19.0 — 2026-09-05
Checked schema imports and structural data realizations
capability · significant impact · release notes
Import complete JSON Schema roots with source identity; generate structural Go, Rust and TypeScript libraries; and run source-pinned normalization recipes. Rust normalization has a library API; Go/TypeScript support is pending. Rust/Web synthesis returns checked failures, and sliced provenance names its digest profile.
0.18.0 — 2026-09-04
An authored scenario can claim that a consumer halted an ordered scan
capability · significant impact · release post · release notes
halts_after: <n> lets an authored scenario require a consumer to stop an ordered scan after n rows. The target reports rows produced and whether the consumer ended the read. Targets without incremental reads report unsupported. This adds a claim to ess-conformance/4.
A specification's scenarios can be played in a browser
capability · significant impact · release post · release notes
ess verify conform web emits a browser page that walks authored scenarios, showing actors, state, selected views, and declared consequences. It replays model-determined behavior without executing an implementation, so authors can inspect a specification before filling its obligations.
0.16.0 — 2026-09-04
A specification carries the scenarios an author wrote, not only the ones it obliges
capability · significant impact · release notes
Authors can declare modelled instances, command timelines, and expectations in ess-scenario/1. These scenarios compile into ess-conformance/2 with identities distinct from synthesized suites. Twenty-seven refusals check their names against the model. Included in the published 0.16.0 release.
An authored scenario can claim a length of time, and a target has to answer for it
capability · significant impact · release notes
Authored scenarios gain mark: and elapsed: with not_before, within, and quiet bounds. The suite states a duration and its anchor; the target reports an observed or advanced clock. Targets without clock support report unsupported. The claims use ess-conformance/3.
0.14.0 — 2026-09-04
A component can declare a command-line surface, and ESS synthesizes its parser
capability · significant impact · release post · release notes
reached_by: command_line and a cli: block state that a component's callers are people at a terminal and where each command sits in the tree. ess generate synthesize --target clap emits the parser, the handler obligations and the completion scripts from that declaration.
0.1.0 — 2026-09-01
ESS becomes a standalone executable specification toolchain
migration · significant impact · release notes
ESS 0.1.0 extracts system modeling, schema contracts, generators, and conformance into an independent repository with no AEP dependency.