What it does
TESSY is a commercial test system for unit and integration testing of embedded C and C++ software on different target systems. It guides teams through project setup, test-case and test-data design, execution, result analysis and reporting. Its workflow also connects tests to requirements and includes code-coverage measurement, so it can support teams that need traceability and evidence for safety-related embedded development as well as ordinary regression work.
Configure a project around its target toolchain
Start by defining a TESSY project structure and its environment variables, then select the compiler and debugger in the integrated Test Environment Editor. The product documentation describes a graphical Classification Tree Editor for designing test cases and a tabular Test Data Editor for entering and plotting data. Run the resulting tests on the configured embedded target, keep each execution as a test run, and inspect the results and coverage in the project view or Coverage Viewer. Requirement links can be imported from supported requirement tools or files and used for coverage and change-impact reports.
TESSY is useful when a team needs more than a pass/fail result. Its product page lists statement, branch, decision, MC/DC, multiple-condition, entry-point, function and call-pair coverage. Version 5.1 adds a Test Cockpit view that summarizes executed tests and coverage by source file, with Code Access and Hyper Coverage features for source variants. These are vendor-documented capabilities, not results from a test run performed here.
Licensing is commercial: the licensing FAQ describes node-locked, floating and CI licenses. The CI license is for headless pipeline execution and depends on a floating-license-server arrangement; the FAQ says that server must run on Windows, although Linux TESSY clients can use it. Razorcat's public pages do not establish current purchase rates, so confirm licensing and target/compiler compatibility with the vendor before budgeting.
Strengths
- The documented workflow covers test project organization, compiler/debugger configuration, test design, execution, analysis and reporting.
- The Classification Tree Editor and tabular Test Data Editor support structured test-case and test-data work.
- Tests can be linked to requirements for traceability, coverage analysis and impact review.
- Coverage options include branch, MC/DC and other code measures, with a Coverage Viewer and source-level Test Cockpit summary.
- The licensing FAQ describes a CI license for headless use in automated pipelines.
Watch out for
- A project must be configured for its compiler, debugger and target environment, which makes toolchain fit part of setup.
- The CI license is headless-only and uses a floating-license server on Windows; Linux clients can use that server but do not remove the server requirement.
Best for
- Embedded C/C++ teams building repeatable unit and regression suites across target systems.
- Safety-related development teams that need code coverage, requirement traceability and execution records.
- Organizations running embedded tests in CI that can provision a Windows floating-license server.
Sources
- TESSY - Test System (Oct 25, 2026)
- TESSY - Test System (Oct 25, 2026)
- FAQ TESSY 5.1 (Oct 25, 2026)
- TESSY - licensing FAQs - Hitex GmbH (Oct 25, 2026)
- Coverage Measurement in TESSY (Oct 25, 2026)