The Flat Map That Grew Three Dimensions
The CaseContext in casehub-engine has been, since the beginning, a flat Map<String, Object>. Workers write their output into it, the engine writes its signals — actionGateRejected, workItemEscalated, whatever — and domain initialization data lands there too. One namespace for everything.
This was always a collision waiting to happen. A worker that returns a key named actionGateRejected would silently trigger engine behaviour. Semantic domain knowledge — the fraud threshold for a fraud-check case, the entity ID for a clinical trial — lives alongside mutable worker outputs with no distinction.
We wanted to fix this properly: named panels with typed access. Working memory (mutable, worker-owned), semantic memory (read-only domain context injected at case start), episodic memory (event history — what happened in this case run, plus inter-case history from prior cases). The design went through six revision rounds before implementation began.
Three things turned out to be non-obvious.
The asJsonNode() change is a breaking change for every JQ expression. CaseContext.asJsonNode() now returns a panel document: {"working":{...},"semantic":{...},"episodic":{...}}. Every binding filter, every inputSchema, every goal condition that previously wrote .result now needs .working.result. Mechanically simple; the surprise is the blast radius — 47 test files across four modules needed updating. A parse-time warning in CaseDefinitionYamlMapper catches unmigrated expressions without blocking load.
@ConsumeEvent is compiled at build time. The design called for panel-scoped Vert.x addresses — casehub.context.changed.extracted for user-defined panels, so bindings could subscribe only to the panel they care about. But @ConsumeEvent is a Quarkus Arc annotation resolved at build time, not runtime. There is no equivalent to eventBus.consumer("dynamic.address", handler) via annotation. The fix: a single @ConsumeEvent handler on the base address, with a changedPanel field in the event. The handler reads that field to filter binding evaluation. Panel-scoped addresses are still published for external consumers.
Recovery must reconstruct panels, not flatten them. CaseStartedEventHandler stores instance.getCaseContext().asJsonNode() as the CASE_STARTED payload. After the semantics change, that payload is the full panel document. The recovery service was constructing context via new CaseContextImpl(payloadAsMap(payload)) — which would have taken {"working":{...},"semantic":{...},"episodic":{...}} and made “working”, “semantic”, and “episodic” into flat working panel keys. No error thrown; the recovered case would have had completely wrong state. The fix is CaseContextImpl.fromPanelDocument(payload), which reads the panel keys and reconstructs each panel correctly.
Claude’s code review surfaced two correctness bugs we had missed. The deep-copy utility recursed into nested Map values correctly but created new ArrayList<>(list) for List values — shallow-copying any maps inside those lists. The episodic workers list aliased its entries between a snapshot and the original, corrupting trigger evaluation. The second: the read-modify-write on the episodic panel was not atomic. getList() reads under the read lock and releases it; the modification runs unlocked; set() re-acquires the write lock. Under concurrent Quartz worker completions, the later write overwrites the earlier’s increment. Both fixed via an engineUpdate() method that holds the write lock for the full sequence.
The episodic panel ended up with two sub-sections. The intra-case section is rebuilt from EventLog on recovery and updated by the engine after each worker completion or milestone. The inter-case section queries ReactiveCaseMemoryStore at case start, giving workers access to prior history for the same entity across all previous cases. The query must not include withCaseId(currentCaseId) — a brand-new case has no stored memories, so that filter always returns empty.
The Drools integration that depends on all this — WorkingMemoryBridge, typed facts from named panels — is the next piece.