strata-org/Strata
Aug 2025 – Jun 2026
3 Months active
Languages Used
LeanC#Markdown
Technical Skills
BoogieCompiler TransformationsFormal VerificationStatic AnalysisTheorem ProvingCI/CD
David Deng
PROFILE
David Deng
Worked on the strata-org/Strata repository to advance formal verification and compiler infrastructure, focusing on semantic-preserving program transformations and flexible control-flow modeling. Delivered formal proofs for call-elimination and deterministic-to-nondeterministic transformations in Boogie, using Lean for theorem proving and static analysis to improve transformation reliability. Enhanced the verification pipeline by introducing a sum-type representation for procedure bodies, supporting both structured statements and deterministic control-flow graphs, and updated the parser, type system, and documentation accordingly. Improved CI/CD workflows and onboarding documentation, addressed namespace collisions, and strengthened type handling, demonstrating depth in compiler design, functional programming, and program verification using C# and Lean.
Overall Statistics
Feature vs Bugs
100%Features
Repository Contributions
4Total
Bugs
0
Commits
4
Features
4
Lines of code
10,541
Activity Months3
Your Network
27 peopleWork History
June 2026
1 Commits • 1 Features
Jun 1, 2026June 2026 monthly summary for strata-org/Strata Overview: - Focused on enabling flexible control-flow modeling inside Procedure.Body by introducing a sum-type representation that supports both structured statements and deterministic CFGs. This lays groundwork for more precise verification, richer IRs, and future CFG-driven optimizations, while maintaining stability of the existing structured-path verification. Key features delivered: - Implemented Procedure.Body as a sum type with two arms: .structured (List Statement) and .cfg DetCFG, plus supporting type infrastructure and projections. This enables a unified representation for both structured and CFG-based bodies. - Added DetCFG alias and extended the verification pipeline to thread consumer state through the new sum type (consumer threading across verification steps). - DDParser/DDM support for CFG syntax: added parser categories and translation paths to produce Procedure.Body.cfg, enabling end-to-end CFG-based procedure representation. - DDM translator updates to build Procedure.Body.cfg from parsed CFG blocks and transfers; existing structured-path translation remains intact. - Examples, tooling, and docs: included sample CFG procedures (Examples/CFGSimple.core.st, Examples/CFGNondet.core.st), and updated docs and editors for CFG keywords highlighting. - Build and test readiness: 44 files touched across 5 layers (~714 lines of addition for the new CFG path), with lake build green and lake test green aside from environment-managed dependencies. Major bugs fixed / stability work: - Stabilized integration of the CFG path with the existing verification pipeline by introducing safe stubs for .cfg arms in consumer code paths (13 consumers), allowing mainline land to proceed while infra and full CFG back-ends are developed in parallel. No regressions observed in the structured-path flow. - Adapted WF predicates and verification bridging (via procToVerifyStmt_is_structured bridge and CoreBodyExec updates) to accommodate the new sum type, enabling consistent reasoning across both structured and CFG bodies. Overall impact and accomplishments: - Business value: Enables richer and more precise modeling of procedures, reducing verification gaps for complex control flow, which supports stronger correctness guarantees and potential performance improvements in optimization and verification passes. - Technical accomplishments: end-to-end support for CFG-based bodies including parsing, translation, verification integration, and example-driven validation, with substantial codebase impact and clear separation from the companion infra work. - Technologies/skills demonstrated: Lean type-system extension, DDM/CFG grammar, parser/translator design, verification pipeline threading, CFG-based code generation, documentation and tooling updates.
1 Commits • 1 Features
Jun 1, 2026June 2026 monthly summary for strata-org/Strata Overview: - Focused on enabling flexible control-flow modeling inside Procedure.Body by introducing a sum-type representation that supports both structured statements and deterministic CFGs. This lays groundwork for more precise verification, richer IRs, and future CFG-driven optimizations, while maintaining stability of the existing structured-path verification. Key features delivered: - Implemented Procedure.Body as a sum type with two arms: .structured (List Statement) and .cfg DetCFG, plus supporting type infrastructure and projections. This enables a unified representation for both structured and CFG-based bodies. - Added DetCFG alias and extended the verification pipeline to thread consumer state through the new sum type (consumer threading across verification steps). - DDParser/DDM support for CFG syntax: added parser categories and translation paths to produce Procedure.Body.cfg, enabling end-to-end CFG-based procedure representation. - DDM translator updates to build Procedure.Body.cfg from parsed CFG blocks and transfers; existing structured-path translation remains intact. - Examples, tooling, and docs: included sample CFG procedures (Examples/CFGSimple.core.st, Examples/CFGNondet.core.st), and updated docs and editors for CFG keywords highlighting. - Build and test readiness: 44 files touched across 5 layers (~714 lines of addition for the new CFG path), with lake build green and lake test green aside from environment-managed dependencies. Major bugs fixed / stability work: - Stabilized integration of the CFG path with the existing verification pipeline by introducing safe stubs for .cfg arms in consumer code paths (13 consumers), allowing mainline land to proceed while infra and full CFG back-ends are developed in parallel. No regressions observed in the structured-path flow. - Adapted WF predicates and verification bridging (via procToVerifyStmt_is_structured bridge and CoreBodyExec updates) to accommodate the new sum type, enabling consistent reasoning across both structured and CFG bodies. Overall impact and accomplishments: - Business value: Enables richer and more precise modeling of procedures, reducing verification gaps for complex control flow, which supports stronger correctness guarantees and potential performance improvements in optimization and verification passes. - Technical accomplishments: end-to-end support for CFG-based bodies including parsing, translation, verification integration, and example-driven validation, with substantial codebase impact and clear separation from the companion infra work. - Technologies/skills demonstrated: Lean type-system extension, DDM/CFG grammar, parser/translator design, verification pipeline threading, CFG-based code generation, documentation and tooling updates.
June 2026
May 2026
2 Commits • 2 Features
May 1, 2026May 2026 performance summary for strata-org/Strata: Focused on onboarding-friendly CI setup, robust verification workflows, and targeted improvements to the Strata backend. Delivered clear CI/docs, strengthened type handling, and improved Boogie/SMACK integration to reduce verification friction and increase reliability.
May 2026
2 Commits • 2 Features
May 1, 2026May 2026 performance summary for strata-org/Strata: Focused on onboarding-friendly CI setup, robust verification workflows, and targeted improvements to the Strata backend. Delivered clear CI/docs, strengthened type handling, and improved Boogie/SMACK integration to reduce verification friction and increase reliability.
August 2025
1 Commits • 1 Features
Aug 1, 2025August 2025 monthly summary for strata-org/Strata: Delivered formal verification proofs for call-elimination and deterministic-to-nondeterministic transformations in Boogie-based Strata, improving semantic preservation and confidence in automated transformations. Fixed several errors in the nondeterministic transformation proof and integrated corrections into SemanticsProps.lean. Commit 74e7be4a623a99b15e8c3be30b1f63691fab49bb (“Call Elimination Correctness Proof #37”). This work reduces transformation risk, enhances reliability, and enables safer refactoring and optimization pipelines.
1 Commits • 1 Features
Aug 1, 2025August 2025 monthly summary for strata-org/Strata: Delivered formal verification proofs for call-elimination and deterministic-to-nondeterministic transformations in Boogie-based Strata, improving semantic preservation and confidence in automated transformations. Fixed several errors in the nondeterministic transformation proof and integrated corrections into SemanticsProps.lean. Commit 74e7be4a623a99b15e8c3be30b1f63691fab49bb (“Call Elimination Correctness Proof #37”). This work reduces transformation risk, enhances reliability, and enables safer refactoring and optimization pipelines.
August 2025
Activity
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Quality Metrics
Correctness90.0%
Maintainability85.0%
Architecture85.0%
Performance80.0%
AI Usage40.0%
Skills & Technologies
Programming Languages
C#LeanMarkdown
Technical Skills
BoogieCI/CDCompiler TransformationsFormal VerificationStatic AnalysisTheorem Provingcompiler designdependency managementdocumentationfunctional programmingprogram verificationsoftware testingstatic analysistype systemstype theory
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