Seapie
a Python debugger where breakpoints drop into a REPL
Details
- External ID
- 46588032
- Source
- HN
- Company
- —
- Product
- Seapie
- Website domain
- github.com
- Launched
- Jan. 12, 2026
- Cohort
- —
- Upvotes
- 22
- Upvotes percentile
- 0.66600790513834
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
Author here.I started seapie as a reaction to pdb's command-driven interface in 2019. I wanted a breakpoint to simply mean 'open a Python REPL here', with debugging functionality layered on top instead of replacing the REPL.`seapie.breakpoint()` opens a working `>>>` REPL at the current execution state. Any changes to variables or function definitions persist. Debugger state is exposed via built-ins (e.g. `_magic_`), and stepping/frame control/etc is handled via small `!commands`.I've been using this regularly in my own work for a few years now. Happy to answer questions or hear criticism, especially from people who've used debuggers heavily.
Enrichment
- Theme
- system maintenance and file utilities
- Vertical
- —
- Function
- Dev tools
- Audience
- Developer
- AI stance
- Not AI
- Project type
- Hobby / open-source project
- Normalized one-liner
- python debugger with repl breakpoints
- Manually corrected
- False
Could you build this?
Partial Creating a standard Python wrapper around `code.InteractiveConsole` is easy, but building a production debugger that intercepts frame execution, preserves stack context, and injects interactive REPL sessions into live execution without corrupting interpreter state is tricky.
What it would actually take: This requires tapping directly into CPython's execution tracing mechanisms via `sys.settrace`, manipulating PyFrameObjects, and managing standard I/O redirection. The debugger must construct a custom evaluation environment from `frame.f_locals` and `frame.f_globals` and handle variable updates safely back into the runtime frame. Solid expertise in CPython internal mechanics and runtime frame evaluation is needed.
Discussion
9 comments analyzed.
Competitors mentioned: pdb (Python debugger), pudb (TUI debugger), ipdb (IPython debugger), IDE debuggers (Cursor, VS Code, etc.), extipy (Jupyter notebook debugging)
Concerns raised: Lacks IDE features like automatic variable preview and call stack visualization, Requires manual typing of commands vs. IDE's automatic display of program state, Not useful for IDE users who already have integrated debugging for 20+ years, Breakpoint hit indication not immediately obvious without explicit commands, CLI-only approach slower than visual debugger for heavy debugging workflows
Feature requests: Auto-display current line and breakpoint info on hit, Variable preview panel showing types, shapes, first values without manual print, Call stack visualization without typing commands, Better display of numpy arrays, lists, and complex objects, Dev container support with standardized debugging environments
Competitors
Other products that read as similar to this one — 74 launches clear the similarity bar, closest 8 shown.
Attention rank: #37 of 75 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Launched 70 days after the earliest competitor.
- PipeStep · hn · 2026-03-12 · 12 upvotes · similarity 0.49
- Retrace · hn · 2026-05-12 · 14 upvotes · similarity 0.43
- Memory Graph · hn · 2026-01-05 · 7 upvotes · similarity 0.42
- Ced · hn · 2026-05-07 · 5 upvotes · similarity 0.41
- I built a post-mortem debugger for native Windows x64/x86 crashes · hn · 2026-09-23 · 37 upvotes · similarity 0.40
- Dap-mux · hn · 2026-06-06 · 7 upvotes · similarity 0.40
- Diffswarm · hn · 2026-01-06 · 8 upvotes · similarity 0.39
- Dbg · hn · 2026-04-13 · 7 upvotes · similarity 0.38
Other launches for this product
- No other launches for this product.