Decidable By Construction: Design-Time Verification for Truly Fearless Systems
Organizations: SpeakEZ Technologies, Asheville, NC
Abstract
Concurrency, parallelism and distributed execution become truly fearless when the compiler tracks wait-for edges, proves multi-threaded work is sound and preserves distributed boundary contracts. In this design, our Composer compiler preserves proofs while lowering Clef directly to native CPU, GPU, NPU and FPGA code, without translation through C or vendor APIs. Our Program Semantic Graph retains the values, relationships and premises that justify BAREWire's unboxed boundary contracts. And C & C++ interfacing is an explicit marshaling boundary, with proofs tied to actual arguments, conversions and returned values. Four verification tiers connect an account of our design. Tier 1 supplies structural inference, founded on principal dimensional types. Tier 2 generates and checks local arithmetic, representation, and computational integrity at the node level. Tier 3 instantiates reusable domain and system lemmas, including distributed proofs supported by Iris, Actris and Aneris. Tiers 1-3 require no developer annotations, with a quotation based lemma library design to extend coverage as use cases expand. Tier 4 admits computational and probabilistic relational proofs, with project annotations identifying the required relations. We extend the same library direction toward recognizing relational constructions from hypergraph structure. A formal composition rule connects arithmetic, ownership, protocol and realization evidence. Our worked distributed reduction preserves one specified result across concurrent workers, reordered arrivals and boundary mappings. Its probabilistic extension carries worker and conversion error with an explicit failure budget. With recent work by Urschel, we show bounds supply a relevant source of reusable proof terms. These constructions make verification a core engineering discipline for truly fearless programs and systems across a variety of hardware targets.
Figures & tables
| Concern | Active execution | Replacement preparation and publication |
|---|---|---|
| Persistent resources | Published code, configuration and retained state | Candidate version and any state-conversion resources |
| Temporary storage | Live calls, buffers and queued work | Update computation, transfer and validation buffers |
| Admission evidence | Premises supporting the current operations | Evidence for the candidate's interfaces, behavior and realization |
| Version and lifetime | A coherent version remains valid for each use | Atomic publication and justified retirement of superseded resources |
| Tier | Judgment | Compiler and library contribution |
|---|---|---|
| 1 | Structural relationships in admitted type interpretations | Automatic dimensional inference and established structural or parametricity rules |
| 2 | Local arithmetic, range and representation conditions | Compiler-generated obligations checked in supported analysis and decision fragments |
| 3 | Parameterized domain and system contracts | Automatic selection and instantiation of registered lemmas from program and hypergraph structure |
| 4 | Relations between computations, distributions or realizations | Project-specific relational annotations, with reusable rule libraries and structural recognition intended to extend automatic coverage |
| Mechanism | Establishes or supports | Costs that remain |
|---|---|---|
| Convex projection | Membership in a specified feasible set, under the implementation's arithmetic contract | Projection evaluation, unless statically proved redundant |
| Residual or penalty objective | A specified discrepancy and its contribution to an optimization criterion | Residual evaluation and evidence for the required accuracy or feasibility |
| Lookup and selection | Retrieval under a specified key or selection policy | Lookup, version handling, conversion and required validation |
| Typed elaboration | The admitted structural and proof obligations | Constraint solving, preservation checks and necessary runtime boundary validation |
| Assessment | Required positive evidence | Discriminating change |
|---|---|---|
| Automatic Tier 2/3 coverage | Ordinary reduction and protocol code generates the applicable conditions and lemma instance | A construction outside the registered law produces a specific coverage diagnostic |
| Argument and boundary binding | The source value, actual call operand, representation conversion and receiver use share a justified correspondence | Changing the actual operand or receiving contract invalidates the affected instance even if an arithmetic answer is unchanged |
| Concurrent acceptance | Reordering and duplicating arrivals preserves the accepted-set and accumulator invariants | Separating freshness testing from the atomic acceptance transition exposes the duplicate-admission obligation |
| Relational realization | Each admitted partition and target implementation preserves the selected observation relation | A changed rounding order, width, signedness or emitted operation requires the corresponding new relation or evidence |
| Error and failure budgets | Worker error, boundary conversion and failure events compose to the application contract | A fresh randomized retry or altered observation policy changes the relevant risk account |
| Direct composition across tiers | A checked Tier 2 bound becomes a premise in a Tier 4 proof term through its registered interface | Rebinding the bound to another value or removing a receiving-rule premise invalidates the application |