UDB
What UDB is
UDB is a paid interactive time-travel debugger for Linux C and C++ programs. It records execution so developers can replay a run, move forward or backward, and inspect variables and memory. Users can launch a program in UDB or attach it to a running process. Features include scripting, conditional and exception breakpoints, watchpoints, core-dump debugging, and remote debugging. UDB is described as 100% compatible with GDB while adding time-travel commands. Named integrations include Visual Studio Code, CLion, Eclipse, and Emacs; the Eclipse integration is marked experimental. Its explain command allows an AI coding assistant to investigate an issue through an Undo recording. Setup requires no compilation or build changes and no kernel or system configuration. The documented engine requires 64-bit Linux, supports 32-bit and 64-bit x86 processes, and offers opt-in ARM support. It handles user-space code, not kernel-space code. Pricing is on request, and a free trial is available.
Who it suits
UDB suits Linux developers working in C or C++ who need replayable debugging for issues such as race conditions, deadlocks, memory corruption, segfaults, or stack corruption. It is for user-space code rather than kernel-space code.
What it does well
- Replays execution in forward and reverse directions
- Inspects variables and memory
- Compatible with GDB
- Offers several named IDE integrations
- Requires no build or kernel configuration changes
What to know first
- Engine does not support Windows or macOS
- Kernel-space code is not supported
- ARM support is opt-in
- Pricing is available on request
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Land and Prove Program | $50K program entry fee · unlimited development access for 6 months · development and CI environments; production debugging priced after assessment | $50,000, paid once |
As undo.io lists them, read 3 Oct 2026. The maker's own page has the final word.
Verdict
UDB combines recording-based replay with conventional debugging controls for Linux C and C++ work. Its platform and user-space limits matter, but the free trial provides a way to evaluate it before purchase.
Facts from UDB's own pages
- AI debugging
- UDB's explain command lets an AI coding assistant drive the debugger using an Undo recording to investigate a problem. · undo.io, 3 Oct 2026
- Debugging
- UDB supports forward and reverse execution with variable and memory inspection, scripting, conditional breakpoints, and watchpoints. · undo.io, 3 Oct 2026
- GDB compatibility
- Undo says UDB is 100% compatible with GDB and adds a handful of commands for time travel debugging. · undo.io, 3 Oct 2026
- Headquarters
- Cambridge, UK · undo.io, 28 Sept 2026
- IDE integrations
- The product page names Visual Studio Code, CLion, Eclipse, and Emacs integrations; the Eclipse guide labels that integration experimental. · undo.io, 3 Oct 2026
- Intended users
- Undo describes UDB as suited to individual developers and highlights race conditions, deadlocks, memory corruption, segfaults, and stack corruption as debugging use cases. · undo.io, 3 Oct 2026
- Kernel-space limit
- UDB supports user-space code only, not kernel-space code. · undo.io, 3 Oct 2026
- Operating system limit
- The engine does not support non-Linux operating systems such as Windows or macOS. · docs.undo.io, 3 Oct 2026
- Purpose
- UDB is an interactive time travel debugger for Linux C/C++ that records program execution so developers can replay it and inspect state. · undo.io, 3 Oct 2026
- Security and evaluation
- Undo says customers can evaluate UDB within their firewall without sending anything externally. · undo.io, 3 Oct 2026
- Setup
- Undo says UDB requires no compilation or build changes and no kernel or system configuration. · undo.io, 3 Oct 2026
- Supported environment
- The documented engine requires 64-bit Linux and supports 32-bit and 64-bit x86 processes with standard license configurations; ARM support is opt-in. · docs.undo.io, 3 Oct 2026
- Team support
- The enterprise team package includes white-glove support with direct access to Undo's engineering team. · undo.io, 3 Oct 2026
- Trial
- Undo offers a free trial, but the pages opened here do not state its duration. · undo.io, 3 Oct 2026
- Workflow
- Users can launch a program in UDB or attach it to a running process. · undo.io, 3 Oct 2026
Where UDB stands on Freedom251
- Debuggers#21 of 27