Productivity · Weekend build
Build your own Todoist
Capture the task, see today, check it off. Todoist charges $5–$8 per person per month — that’s $60–$96 a year per person — for something you can replace with focused software of your own. Here is the honest scope, the honest timeline, and the exact prompt to hand your coding agent.
Who this replacement is for
This build targets one person managing personal and freelance commitments. The goal: capture tasks instantly and trust a calm daily view with recurring work. If you need more than that, keep paying — the point of building it yourself is owning a tool shaped exactly like your workflow, not re-implementing a venture-funded roadmap.
Same build, different logo: this v1 also replaces TickTick, Things 3 and Any.do — they all solve the same core job.
How long it actually takes
One number would be a lie, so here are three. Each tier is a real, usable product — pick the one that matches how much of Todoist you actually use.
| Estimate | What you get |
|---|---|
| 8 hours | quick add, today view, check off |
| 3 days | recurring tasks, labels, saved filters, reminder email |
| 1 month+ | native apps, offline sync, calendar integration — the part you should probably skip |
What a minimal Todoist alternative needs
- quick add with project, due date, priority, labels, and natural date shortcuts
- Inbox, Today, Upcoming, project, and label views
- recurring tasks with complete-and-advance behavior
- subtasks, notes, search, and saved filters
- daily reminder email and completed-task history
Data model
Project, Task, Label, TaskLabel, Reminder, Completion
Integrations
transactional email
Capability context
Astro, HTMX, D1
The guardrail
Store timezone context for due dates, make recurrence advancement atomic, and never lose completion history when a repeating task moves forward.
Deliberate non-goals
Do not build team workspaces, calendar sync, chat, kanban, habits, location reminders, or native apps.
The complete build prompt
Copy this into your coding agent of choice. It is scoped for a useful v1 — journeys, screens, business rules, data model, security, tests, and acceptance scenarios included. Pick your stack:
You are building a production-ready software product named “Dolist”, a deliberately focused alternative to Todoist. Build a complete, usable vertical slice—not a landing page, static mockup, or disconnected collection of components. WORKING AGREEMENT Before writing implementation code, produce a short technical plan that names the routes or pages, server actions or endpoints, data tables, important state transitions, authorization boundaries, background jobs, and external adapters. Resolve contradictions in favor of the narrow audience and non-goals below. Prefer a small, legible architecture over speculative abstraction, but do not omit persistence, validation, error handling, or tests. PRODUCT BRIEF Primary user: one person managing personal and freelance commitments. Primary outcome: capture tasks instantly and trust a calm daily view with recurring work. Product principle: optimize the exact workflow below instead of copying the full breadth of Todoist. A first-time user should understand what to do from the interface itself, without a tour or documentation. END-TO-END USER JOURNEYS Implement all of these flows through the real interface and persistent data layer: 1. The user quick-adds tasks into the Inbox with natural date shortcuts, assigns projects, priorities, and labels, and organizes the Today view. 2. The user completes a recurring weekly task, sees the next occurrence advance correctly in their timezone, and later reviews the completion history. 3. The user builds and saves an overdue high-priority filter, receives one daily reminder email, reschedules two tasks, and archives a finished project. SCREENS AND INFORMATION ARCHITECTURE Build these as coherent responsive views. Each screen must specify its primary action, secondary actions, visible status, validation feedback, empty state, loading or pending state, success confirmation, and recoverable failure state. 1. Inbox and quick add: task text, parsed date preview, project, priority, labels, validation, keyboard flow, pending save, and undo. 2. Today and Upcoming: grouped dates, overdue state, complete, postpone, edit, subtask progress, empty celebration, and timezone context. 3. Project and filter: ordered tasks, notes, labels, saved query builder, matching preview, archive, restore, and completed history. 4. Settings: timezone, daily reminder time, date-shortcut examples, data export, completed retention, and account deletion. CORE CAPABILITIES 1. quick add with project, due date, priority, labels, and natural date shortcuts 2. Inbox, Today, Upcoming, project, and label views 3. recurring tasks with complete-and-advance behavior 4. subtasks, notes, search, and saved filters 5. daily reminder email and completed-task history DETAILED BEHAVIOR AND BUSINESS RULES Treat these as server-enforced product requirements, not interface suggestions: 1. Keep due date-only values separate from timed instants, retain the owner timezone for reminders, and show the parsed result before saving natural-language dates. 2. Completing a recurring task records an immutable completion and atomically calculates the next occurrence from the recurrence rule rather than from arbitrary delay. 3. Tasks and subtasks keep stable order, cannot form cycles, and archived projects disappear from active views without deleting completion history. 4. Generate at most one daily reminder per user and local date with an idempotency key; retries cannot duplicate email. DATA MODEL AND LIFECYCLE Design a small relational schema centered on Project, Task, Label, TaskLabel, Reminder, Completion. Before implementing it, document: 1. Each table’s purpose, primary key, ownership or tenant boundary, timestamps, status fields, and important attributes. 2. Foreign keys, uniqueness constraints, check constraints, indexes needed by the named screens, and transaction boundaries for multi-record changes. 3. The allowed lifecycle or state transitions, who may trigger each transition, which transitions are terminal or reversible, and what audit history must remain immutable. 4. Archive, retention, and deletion behavior, including what happens to dependent records and external files. 5. Idempotency strategy for submissions, jobs, imports, notifications, webhooks, or retries where applicable. Use migrations rather than ad-hoc schema creation. Store time instants consistently and retain named timezone context whenever local schedules or dates matter. Never rely on a counter, disabled button, or client-side check to preserve a business invariant. USERS, AUTHENTICATION, AND PERMISSIONS Implement only the roles required by the stated audience. Make the ownership and visibility model explicit before coding. Enforce authorization in every server-side query and mutation, including search, exports, attachments, live updates, and guessed URLs—not merely by hiding controls. Use secure session defaults, protect state-changing requests, and provide an understandable signed-out, expired-session, and forbidden state. Seed distinct users when multiple roles are required so permissions can be demonstrated and tested. INTERACTION AND VISUAL DIRECTION The product should feel fast, calm, focused, and credible rather than like a generic admin template. Use a clear visual hierarchy, restrained color, readable typography, generous hit targets, and consistent placement for primary actions. Start with server-rendered HTML and progressively enhance only the interactions that benefit from it. The core workflow must remain understandable if enhancement fails. Start with server-rendered Astro pages and ordinary HTML forms. Use HTMX for form submissions, partial navigation, and server-driven updates, then Alpine.js only for small local browser state. The core workflow must remain understandable if either enhancement layer fails. Design mobile layouts intentionally instead of simply stacking desktop panels. Support keyboard navigation, visible focus, semantic landmarks, explicit labels, useful page titles, reduced-motion preferences, and screen-reader announcements for asynchronous results. Never use color alone to communicate state. Destructive actions require clear scope and confirmation; safe repeated actions should be idempotent. TECHNICAL DIRECTION Build this version with the AHA stack: Astro for routing, layouts, and server-rendered pages; HTMX for interactions that benefit from HTML fragment responses; and Alpine.js for small, local interface state. Prefer Cloudflare D1 for relational persistence, R2 for object storage, Workers for server endpoints and scheduled work, Durable Objects only for coordinated real-time state, and Workflows or Queues for durable background jobs—but only when the product requirements call for them. Keep domain rules in testable server-side modules instead of route handlers or UI components. Separate persistence, external providers, and background work behind small interfaces without building a framework. Prefer ordinary HTML forms and URLs for durable navigation; use optimistic interaction only when failure can be reconciled clearly. The product brief currently identifies Astro, HTMX, D1 as capability context. Preserve any required native, browser-only, edge, storage, real-time, or background-processing capability through a narrow adapter appropriate to the selected framework. If the core workflow genuinely requires native or browser APIs, keep that runtime as the primary execution surface rather than simulating inaccessible capabilities or inventing an unnecessary web surface. Integrate with transactional email. For every integration: - List required environment variables in an .env.example without real secrets. - Add a small adapter with timeouts, normalized errors, and a deterministic local fake or development path. - Verify inbound signatures and deduplicate provider events where supported. - Keep credentials server-side, encrypt long-lived provider tokens at rest, and redact secrets and sensitive payloads from logs. - Define retry, backoff, and idempotency behavior for any side effect that can be repeated. SECURITY AND PRIVACY Store timezone context for due dates, make recurrence advancement atomic, and never lose completion history when a repeating task moves forward. Validate, normalize, and length-limit all untrusted input on the server. Escape rendered content by default, sanitize any intentionally accepted markup, rate-limit public or abuse-prone actions, and use private object storage plus short-lived authorized URLs for sensitive files. Collect the minimum personal data necessary for the named workflow. Document retention and deletion behavior. Add specific protections for the riskier surfaces in this app, such as uploads, redirects, outbound requests, email delivery, OAuth, webhooks, CSV import or export, and real-time connections. ACCEPTANCE SCENARIOS Automate these app-specific scenarios at the most appropriate level: 1. Given a weekly task completed around a daylight-saving transition, the next occurrence remains on the intended local weekday and time. 2. Given an invalid natural date phrase, the task text is preserved, no wrong due date is guessed, and correction is clear. 3. Given a reminder job retries, the user receives one email containing the correct overdue and due-today tasks. TESTING Add focused unit tests for state transitions, authorization predicates, normalization, date or money calculations, and other risky domain rules. Add integration tests for persistence constraints and each external adapter’s success, timeout, retry, and rejection paths. Add at least one browser-level test for every end-to-end journey above, including one small-screen viewport. Tests must use isolated data and run through a documented single command. OPERATIONS AND FAILURE RECOVERY Add structured server logs with request, job, or event correlation IDs but no secrets or unnecessarily sensitive data. Make failures actionable in both the interface and logs. Background work must expose pending, succeeded, failed, and retrying states where relevant; do not silently swallow errors. Include safe database migration and rollback guidance, seed data, backup and restore notes, external-data cleanup behavior, and a basic health or diagnostic path appropriate to the stack. DELIVERABLES Ship the working application, migrations, representative seed data, tests, .env.example, and a concise README. The README must cover prerequisites, local setup, environment variables, migrations, seed and test commands, deployment, integration setup, backup and restore, security decisions, and known limitations. Seed data should exercise the happy path plus at least one empty, failed, overdue, expired, archived, or permission-restricted state relevant to the product. DEFINITION OF DONE The app is complete when a fresh developer can follow the README, create and migrate the database, run the app, sign in as each relevant role, complete every named journey using real persisted data, refresh without losing state, recover from common failures, and use the core interface on phone and desktop. All acceptance scenarios pass, permission boundaries are covered by tests, and no core screen is left as a placeholder. NON-GOALS Do not build team workspaces, calendar sync, chat, kanban, habits, location reminders, or native apps.
You are building a production-ready software product named “Dolist”, a deliberately focused alternative to Todoist. Build a complete, usable vertical slice—not a landing page, static mockup, or disconnected collection of components. WORKING AGREEMENT Before writing implementation code, produce a short technical plan that names the routes or pages, server actions or endpoints, data tables, important state transitions, authorization boundaries, background jobs, and external adapters. Resolve contradictions in favor of the narrow audience and non-goals below. Prefer a small, legible architecture over speculative abstraction, but do not omit persistence, validation, error handling, or tests. PRODUCT BRIEF Primary user: one person managing personal and freelance commitments. Primary outcome: capture tasks instantly and trust a calm daily view with recurring work. Product principle: optimize the exact workflow below instead of copying the full breadth of Todoist. A first-time user should understand what to do from the interface itself, without a tour or documentation. END-TO-END USER JOURNEYS Implement all of these flows through the real interface and persistent data layer: 1. The user quick-adds tasks into the Inbox with natural date shortcuts, assigns projects, priorities, and labels, and organizes the Today view. 2. The user completes a recurring weekly task, sees the next occurrence advance correctly in their timezone, and later reviews the completion history. 3. The user builds and saves an overdue high-priority filter, receives one daily reminder email, reschedules two tasks, and archives a finished project. SCREENS AND INFORMATION ARCHITECTURE Build these as coherent responsive views. Each screen must specify its primary action, secondary actions, visible status, validation feedback, empty state, loading or pending state, success confirmation, and recoverable failure state. 1. Inbox and quick add: task text, parsed date preview, project, priority, labels, validation, keyboard flow, pending save, and undo. 2. Today and Upcoming: grouped dates, overdue state, complete, postpone, edit, subtask progress, empty celebration, and timezone context. 3. Project and filter: ordered tasks, notes, labels, saved query builder, matching preview, archive, restore, and completed history. 4. Settings: timezone, daily reminder time, date-shortcut examples, data export, completed retention, and account deletion. CORE CAPABILITIES 1. quick add with project, due date, priority, labels, and natural date shortcuts 2. Inbox, Today, Upcoming, project, and label views 3. recurring tasks with complete-and-advance behavior 4. subtasks, notes, search, and saved filters 5. daily reminder email and completed-task history DETAILED BEHAVIOR AND BUSINESS RULES Treat these as server-enforced product requirements, not interface suggestions: 1. Keep due date-only values separate from timed instants, retain the owner timezone for reminders, and show the parsed result before saving natural-language dates. 2. Completing a recurring task records an immutable completion and atomically calculates the next occurrence from the recurrence rule rather than from arbitrary delay. 3. Tasks and subtasks keep stable order, cannot form cycles, and archived projects disappear from active views without deleting completion history. 4. Generate at most one daily reminder per user and local date with an idempotency key; retries cannot duplicate email. DATA MODEL AND LIFECYCLE Design a small relational schema centered on Project, Task, Label, TaskLabel, Reminder, Completion. Before implementing it, document: 1. Each table’s purpose, primary key, ownership or tenant boundary, timestamps, status fields, and important attributes. 2. Foreign keys, uniqueness constraints, check constraints, indexes needed by the named screens, and transaction boundaries for multi-record changes. 3. The allowed lifecycle or state transitions, who may trigger each transition, which transitions are terminal or reversible, and what audit history must remain immutable. 4. Archive, retention, and deletion behavior, including what happens to dependent records and external files. 5. Idempotency strategy for submissions, jobs, imports, notifications, webhooks, or retries where applicable. Use migrations rather than ad-hoc schema creation. Store time instants consistently and retain named timezone context whenever local schedules or dates matter. Never rely on a counter, disabled button, or client-side check to preserve a business invariant. USERS, AUTHENTICATION, AND PERMISSIONS Implement only the roles required by the stated audience. Make the ownership and visibility model explicit before coding. Enforce authorization in every server-side query and mutation, including search, exports, attachments, live updates, and guessed URLs—not merely by hiding controls. Use secure session defaults, protect state-changing requests, and provide an understandable signed-out, expired-session, and forbidden state. Seed distinct users when multiple roles are required so permissions can be demonstrated and tested. INTERACTION AND VISUAL DIRECTION The product should feel fast, calm, focused, and credible rather than like a generic admin template. Use a clear visual hierarchy, restrained color, readable typography, generous hit targets, and consistent placement for primary actions. Start with server-rendered HTML and progressively enhance only the interactions that benefit from it. The core workflow must remain understandable if enhancement fails. Render with React Server Components by default. Use Server Actions for authenticated form mutations and add Client Components only for interactions that genuinely require browser state, browser APIs, drag-and-drop, or live updates. The core workflow must remain understandable before client-side JavaScript finishes loading. Design mobile layouts intentionally instead of simply stacking desktop panels. Support keyboard navigation, visible focus, semantic landmarks, explicit labels, useful page titles, reduced-motion preferences, and screen-reader announcements for asynchronous results. Never use color alone to communicate state. Destructive actions require clear scope and confirmation; safe repeated actions should be idempotent. TECHNICAL DIRECTION Build this version with Next.js, the App Router, and TypeScript. Use Server Components by default, Server Actions for authenticated mutations, and Route Handlers for public APIs, OAuth callbacks, webhooks, feeds, uploads, and downloads. Use PostgreSQL through Drizzle ORM with versioned migrations and an isolated test database. Access S3-compatible object storage through a server-only adapter, and run slow or retryable work in a real job or workflow system instead of the request lifecycle. Keep domain rules in testable server-side modules instead of route handlers or UI components. Separate persistence, external providers, and background work behind small interfaces without building a framework. Prefer ordinary HTML forms and URLs for durable navigation; use optimistic interaction only when failure can be reconciled clearly. The product brief currently identifies Astro, HTMX, D1 as capability context. Preserve any required native, browser-only, edge, storage, real-time, or background-processing capability through a narrow adapter appropriate to the selected framework. If the core workflow genuinely requires native or browser APIs, keep that runtime as the primary execution surface rather than simulating inaccessible capabilities or inventing an unnecessary web surface. Integrate with transactional email. For every integration: - List required environment variables in an .env.example without real secrets. - Add a small adapter with timeouts, normalized errors, and a deterministic local fake or development path. - Verify inbound signatures and deduplicate provider events where supported. - Keep credentials server-side, encrypt long-lived provider tokens at rest, and redact secrets and sensitive payloads from logs. - Define retry, backoff, and idempotency behavior for any side effect that can be repeated. SECURITY AND PRIVACY Store timezone context for due dates, make recurrence advancement atomic, and never lose completion history when a repeating task moves forward. Validate, normalize, and length-limit all untrusted input on the server. Escape rendered content by default, sanitize any intentionally accepted markup, rate-limit public or abuse-prone actions, and use private object storage plus short-lived authorized URLs for sensitive files. Collect the minimum personal data necessary for the named workflow. Document retention and deletion behavior. Add specific protections for the riskier surfaces in this app, such as uploads, redirects, outbound requests, email delivery, OAuth, webhooks, CSV import or export, and real-time connections. ACCEPTANCE SCENARIOS Automate these app-specific scenarios at the most appropriate level: 1. Given a weekly task completed around a daylight-saving transition, the next occurrence remains on the intended local weekday and time. 2. Given an invalid natural date phrase, the task text is preserved, no wrong due date is guessed, and correction is clear. 3. Given a reminder job retries, the user receives one email containing the correct overdue and due-today tasks. TESTING Add focused unit tests for state transitions, authorization predicates, normalization, date or money calculations, and other risky domain rules. Add integration tests for persistence constraints and each external adapter’s success, timeout, retry, and rejection paths. Add at least one browser-level test for every end-to-end journey above, including one small-screen viewport. Tests must use isolated data and run through a documented single command. OPERATIONS AND FAILURE RECOVERY Add structured server logs with request, job, or event correlation IDs but no secrets or unnecessarily sensitive data. Make failures actionable in both the interface and logs. Background work must expose pending, succeeded, failed, and retrying states where relevant; do not silently swallow errors. Include safe database migration and rollback guidance, seed data, backup and restore notes, external-data cleanup behavior, and a basic health or diagnostic path appropriate to the stack. DELIVERABLES Ship the working application, migrations, representative seed data, tests, .env.example, and a concise README. The README must cover prerequisites, local setup, environment variables, migrations, seed and test commands, deployment, integration setup, backup and restore, security decisions, and known limitations. Seed data should exercise the happy path plus at least one empty, failed, overdue, expired, archived, or permission-restricted state relevant to the product. DEFINITION OF DONE The app is complete when a fresh developer can follow the README, create and migrate the database, run the app, sign in as each relevant role, complete every named journey using real persisted data, refresh without losing state, recover from common failures, and use the core interface on phone and desktop. All acceptance scenarios pass, permission boundaries are covered by tests, and no core screen is left as a placeholder. NON-GOALS Do not build team workspaces, calendar sync, chat, kanban, habits, location reminders, or native apps.
You are building a production-ready software product named “Dolist”, a deliberately focused alternative to Todoist. Build a complete, usable vertical slice—not a landing page, static mockup, or disconnected collection of components. WORKING AGREEMENT Before writing implementation code, produce a short technical plan that names the routes or pages, server actions or endpoints, data tables, important state transitions, authorization boundaries, background jobs, and external adapters. Resolve contradictions in favor of the narrow audience and non-goals below. Prefer a small, legible architecture over speculative abstraction, but do not omit persistence, validation, error handling, or tests. PRODUCT BRIEF Primary user: one person managing personal and freelance commitments. Primary outcome: capture tasks instantly and trust a calm daily view with recurring work. Product principle: optimize the exact workflow below instead of copying the full breadth of Todoist. A first-time user should understand what to do from the interface itself, without a tour or documentation. END-TO-END USER JOURNEYS Implement all of these flows through the real interface and persistent data layer: 1. The user quick-adds tasks into the Inbox with natural date shortcuts, assigns projects, priorities, and labels, and organizes the Today view. 2. The user completes a recurring weekly task, sees the next occurrence advance correctly in their timezone, and later reviews the completion history. 3. The user builds and saves an overdue high-priority filter, receives one daily reminder email, reschedules two tasks, and archives a finished project. SCREENS AND INFORMATION ARCHITECTURE Build these as coherent responsive views. Each screen must specify its primary action, secondary actions, visible status, validation feedback, empty state, loading or pending state, success confirmation, and recoverable failure state. 1. Inbox and quick add: task text, parsed date preview, project, priority, labels, validation, keyboard flow, pending save, and undo. 2. Today and Upcoming: grouped dates, overdue state, complete, postpone, edit, subtask progress, empty celebration, and timezone context. 3. Project and filter: ordered tasks, notes, labels, saved query builder, matching preview, archive, restore, and completed history. 4. Settings: timezone, daily reminder time, date-shortcut examples, data export, completed retention, and account deletion. CORE CAPABILITIES 1. quick add with project, due date, priority, labels, and natural date shortcuts 2. Inbox, Today, Upcoming, project, and label views 3. recurring tasks with complete-and-advance behavior 4. subtasks, notes, search, and saved filters 5. daily reminder email and completed-task history DETAILED BEHAVIOR AND BUSINESS RULES Treat these as server-enforced product requirements, not interface suggestions: 1. Keep due date-only values separate from timed instants, retain the owner timezone for reminders, and show the parsed result before saving natural-language dates. 2. Completing a recurring task records an immutable completion and atomically calculates the next occurrence from the recurrence rule rather than from arbitrary delay. 3. Tasks and subtasks keep stable order, cannot form cycles, and archived projects disappear from active views without deleting completion history. 4. Generate at most one daily reminder per user and local date with an idempotency key; retries cannot duplicate email. DATA MODEL AND LIFECYCLE Design a small relational schema centered on Project, Task, Label, TaskLabel, Reminder, Completion. Before implementing it, document: 1. Each table’s purpose, primary key, ownership or tenant boundary, timestamps, status fields, and important attributes. 2. Foreign keys, uniqueness constraints, check constraints, indexes needed by the named screens, and transaction boundaries for multi-record changes. 3. The allowed lifecycle or state transitions, who may trigger each transition, which transitions are terminal or reversible, and what audit history must remain immutable. 4. Archive, retention, and deletion behavior, including what happens to dependent records and external files. 5. Idempotency strategy for submissions, jobs, imports, notifications, webhooks, or retries where applicable. Use migrations rather than ad-hoc schema creation. Store time instants consistently and retain named timezone context whenever local schedules or dates matter. Never rely on a counter, disabled button, or client-side check to preserve a business invariant. USERS, AUTHENTICATION, AND PERMISSIONS Implement only the roles required by the stated audience. Make the ownership and visibility model explicit before coding. Enforce authorization in every server-side query and mutation, including search, exports, attachments, live updates, and guessed URLs—not merely by hiding controls. Use secure session defaults, protect state-changing requests, and provide an understandable signed-out, expired-session, and forbidden state. Seed distinct users when multiple roles are required so permissions can be demonstrated and tested. INTERACTION AND VISUAL DIRECTION The product should feel fast, calm, focused, and credible rather than like a generic admin template. Use a clear visual hierarchy, restrained color, readable typography, generous hit targets, and consistent placement for primary actions. Start with server-rendered HTML and progressively enhance only the interactions that benefit from it. The core workflow must remain understandable if enhancement fails. Start with server-rendered Blade views and ordinary forms. Use Livewire for focused server-driven interactions and Alpine.js only for small local interface state. The core workflow must remain understandable without relying on a client-side application shell. Design mobile layouts intentionally instead of simply stacking desktop panels. Support keyboard navigation, visible focus, semantic landmarks, explicit labels, useful page titles, reduced-motion preferences, and screen-reader announcements for asynchronous results. Never use color alone to communicate state. Destructive actions require clear scope and confirmation; safe repeated actions should be idempotent. TECHNICAL DIRECTION Build this version with Laravel, PHP, Blade, Livewire, and Alpine.js. Use controllers and Blade forms for durable navigation, Livewire for focused interactions, Form Requests for validation, Policies and Gates for authorization, and small application actions or services for domain transitions. Use Eloquent with migrations, database constraints, and transactions; Laravel Storage for private S3-compatible files; queued Jobs for retryable work; the Scheduler for recurring work; and Notifications or Mail for email. Keep domain rules in testable server-side modules instead of route handlers or UI components. Separate persistence, external providers, and background work behind small interfaces without building a framework. Prefer ordinary HTML forms and URLs for durable navigation; use optimistic interaction only when failure can be reconciled clearly. The product brief currently identifies Astro, HTMX, D1 as capability context. Preserve any required native, browser-only, edge, storage, real-time, or background-processing capability through a narrow adapter appropriate to the selected framework. If the core workflow genuinely requires native or browser APIs, keep that runtime as the primary execution surface rather than simulating inaccessible capabilities or inventing an unnecessary web surface. Integrate with transactional email. For every integration: - List required environment variables in an .env.example without real secrets. - Add a small adapter with timeouts, normalized errors, and a deterministic local fake or development path. - Verify inbound signatures and deduplicate provider events where supported. - Keep credentials server-side, encrypt long-lived provider tokens at rest, and redact secrets and sensitive payloads from logs. - Define retry, backoff, and idempotency behavior for any side effect that can be repeated. SECURITY AND PRIVACY Store timezone context for due dates, make recurrence advancement atomic, and never lose completion history when a repeating task moves forward. Validate, normalize, and length-limit all untrusted input on the server. Escape rendered content by default, sanitize any intentionally accepted markup, rate-limit public or abuse-prone actions, and use private object storage plus short-lived authorized URLs for sensitive files. Collect the minimum personal data necessary for the named workflow. Document retention and deletion behavior. Add specific protections for the riskier surfaces in this app, such as uploads, redirects, outbound requests, email delivery, OAuth, webhooks, CSV import or export, and real-time connections. ACCEPTANCE SCENARIOS Automate these app-specific scenarios at the most appropriate level: 1. Given a weekly task completed around a daylight-saving transition, the next occurrence remains on the intended local weekday and time. 2. Given an invalid natural date phrase, the task text is preserved, no wrong due date is guessed, and correction is clear. 3. Given a reminder job retries, the user receives one email containing the correct overdue and due-today tasks. TESTING Add focused unit tests for state transitions, authorization predicates, normalization, date or money calculations, and other risky domain rules. Add integration tests for persistence constraints and each external adapter’s success, timeout, retry, and rejection paths. Add at least one browser-level test for every end-to-end journey above, including one small-screen viewport. Tests must use isolated data and run through a documented single command. OPERATIONS AND FAILURE RECOVERY Add structured server logs with request, job, or event correlation IDs but no secrets or unnecessarily sensitive data. Make failures actionable in both the interface and logs. Background work must expose pending, succeeded, failed, and retrying states where relevant; do not silently swallow errors. Include safe database migration and rollback guidance, seed data, backup and restore notes, external-data cleanup behavior, and a basic health or diagnostic path appropriate to the stack. DELIVERABLES Ship the working application, migrations, representative seed data, tests, .env.example, and a concise README. The README must cover prerequisites, local setup, environment variables, migrations, seed and test commands, deployment, integration setup, backup and restore, security decisions, and known limitations. Seed data should exercise the happy path plus at least one empty, failed, overdue, expired, archived, or permission-restricted state relevant to the product. DEFINITION OF DONE The app is complete when a fresh developer can follow the README, create and migrate the database, run the app, sign in as each relevant role, complete every named journey using real persisted data, refresh without losing state, recover from common failures, and use the core interface on phone and desktop. All acceptance scenarios pass, permission boundaries are covered by tests, and no core screen is left as a placeholder. NON-GOALS Do not build team workspaces, calendar sync, chat, kanban, habits, location reminders, or native apps.
You are building a production-ready software product named “Dolist”, a deliberately focused alternative to Todoist. Build a complete, usable vertical slice—not a landing page, static mockup, or disconnected collection of components. WORKING AGREEMENT Before writing implementation code, produce a short technical plan that names the routes or pages, server actions or endpoints, data tables, important state transitions, authorization boundaries, background jobs, and external adapters. Resolve contradictions in favor of the narrow audience and non-goals below. Prefer a small, legible architecture over speculative abstraction, but do not omit persistence, validation, error handling, or tests. PRODUCT BRIEF Primary user: one person managing personal and freelance commitments. Primary outcome: capture tasks instantly and trust a calm daily view with recurring work. Product principle: optimize the exact workflow below instead of copying the full breadth of Todoist. A first-time user should understand what to do from the interface itself, without a tour or documentation. END-TO-END USER JOURNEYS Implement all of these flows through the real interface and persistent data layer: 1. The user quick-adds tasks into the Inbox with natural date shortcuts, assigns projects, priorities, and labels, and organizes the Today view. 2. The user completes a recurring weekly task, sees the next occurrence advance correctly in their timezone, and later reviews the completion history. 3. The user builds and saves an overdue high-priority filter, receives one daily reminder email, reschedules two tasks, and archives a finished project. SCREENS AND INFORMATION ARCHITECTURE Build these as coherent responsive views. Each screen must specify its primary action, secondary actions, visible status, validation feedback, empty state, loading or pending state, success confirmation, and recoverable failure state. 1. Inbox and quick add: task text, parsed date preview, project, priority, labels, validation, keyboard flow, pending save, and undo. 2. Today and Upcoming: grouped dates, overdue state, complete, postpone, edit, subtask progress, empty celebration, and timezone context. 3. Project and filter: ordered tasks, notes, labels, saved query builder, matching preview, archive, restore, and completed history. 4. Settings: timezone, daily reminder time, date-shortcut examples, data export, completed retention, and account deletion. CORE CAPABILITIES 1. quick add with project, due date, priority, labels, and natural date shortcuts 2. Inbox, Today, Upcoming, project, and label views 3. recurring tasks with complete-and-advance behavior 4. subtasks, notes, search, and saved filters 5. daily reminder email and completed-task history DETAILED BEHAVIOR AND BUSINESS RULES Treat these as server-enforced product requirements, not interface suggestions: 1. Keep due date-only values separate from timed instants, retain the owner timezone for reminders, and show the parsed result before saving natural-language dates. 2. Completing a recurring task records an immutable completion and atomically calculates the next occurrence from the recurrence rule rather than from arbitrary delay. 3. Tasks and subtasks keep stable order, cannot form cycles, and archived projects disappear from active views without deleting completion history. 4. Generate at most one daily reminder per user and local date with an idempotency key; retries cannot duplicate email. DATA MODEL AND LIFECYCLE Design a small relational schema centered on Project, Task, Label, TaskLabel, Reminder, Completion. Before implementing it, document: 1. Each table’s purpose, primary key, ownership or tenant boundary, timestamps, status fields, and important attributes. 2. Foreign keys, uniqueness constraints, check constraints, indexes needed by the named screens, and transaction boundaries for multi-record changes. 3. The allowed lifecycle or state transitions, who may trigger each transition, which transitions are terminal or reversible, and what audit history must remain immutable. 4. Archive, retention, and deletion behavior, including what happens to dependent records and external files. 5. Idempotency strategy for submissions, jobs, imports, notifications, webhooks, or retries where applicable. Use migrations rather than ad-hoc schema creation. Store time instants consistently and retain named timezone context whenever local schedules or dates matter. Never rely on a counter, disabled button, or client-side check to preserve a business invariant. USERS, AUTHENTICATION, AND PERMISSIONS Implement only the roles required by the stated audience. Make the ownership and visibility model explicit before coding. Enforce authorization in every server-side query and mutation, including search, exports, attachments, live updates, and guessed URLs—not merely by hiding controls. Use secure session defaults, protect state-changing requests, and provide an understandable signed-out, expired-session, and forbidden state. Seed distinct users when multiple roles are required so permissions can be demonstrated and tested. INTERACTION AND VISUAL DIRECTION The product should feel fast, calm, focused, and credible rather than like a generic admin template. Use a clear visual hierarchy, restrained color, readable typography, generous hit targets, and consistent placement for primary actions. Start with server-rendered HTML and progressively enhance only the interactions that benefit from it. The core workflow must remain understandable if enhancement fails. Start with server-rendered Rails views and ordinary forms. Use Turbo for navigation, submissions, and server-driven updates, then Stimulus only for small browser-side behavior. Do not turn the product into a client-side SPA, and keep the core workflow usable when enhancement fails. Design mobile layouts intentionally instead of simply stacking desktop panels. Support keyboard navigation, visible focus, semantic landmarks, explicit labels, useful page titles, reduced-motion preferences, and screen-reader announcements for asynchronous results. Never use color alone to communicate state. Destructive actions require clear scope and confirmation; safe repeated actions should be idempotent. TECHNICAL DIRECTION Build this version with Ruby on Rails and Hotwire: Turbo for navigation, form submissions, and server-driven updates, and Stimulus for small browser-side behavior. Use RESTful controllers with strong parameters and explicit authorization, with domain transitions in testable models or small application services. Use Active Record migrations plus database-level constraints and transactions; Active Storage with an S3-compatible service for private files; Active Job with a durable queue backend for retryable work; Action Mailer for email; and Action Cable only when live updates are required. Keep domain rules in testable server-side modules instead of route handlers or UI components. Separate persistence, external providers, and background work behind small interfaces without building a framework. Prefer ordinary HTML forms and URLs for durable navigation; use optimistic interaction only when failure can be reconciled clearly. The product brief currently identifies Astro, HTMX, D1 as capability context. Preserve any required native, browser-only, edge, storage, real-time, or background-processing capability through a narrow adapter appropriate to the selected framework. If the core workflow genuinely requires native or browser APIs, keep that runtime as the primary execution surface rather than simulating inaccessible capabilities or inventing an unnecessary web surface. Integrate with transactional email. For every integration: - List required environment variables in an .env.example without real secrets. - Add a small adapter with timeouts, normalized errors, and a deterministic local fake or development path. - Verify inbound signatures and deduplicate provider events where supported. - Keep credentials server-side, encrypt long-lived provider tokens at rest, and redact secrets and sensitive payloads from logs. - Define retry, backoff, and idempotency behavior for any side effect that can be repeated. SECURITY AND PRIVACY Store timezone context for due dates, make recurrence advancement atomic, and never lose completion history when a repeating task moves forward. Validate, normalize, and length-limit all untrusted input on the server. Escape rendered content by default, sanitize any intentionally accepted markup, rate-limit public or abuse-prone actions, and use private object storage plus short-lived authorized URLs for sensitive files. Collect the minimum personal data necessary for the named workflow. Document retention and deletion behavior. Add specific protections for the riskier surfaces in this app, such as uploads, redirects, outbound requests, email delivery, OAuth, webhooks, CSV import or export, and real-time connections. ACCEPTANCE SCENARIOS Automate these app-specific scenarios at the most appropriate level: 1. Given a weekly task completed around a daylight-saving transition, the next occurrence remains on the intended local weekday and time. 2. Given an invalid natural date phrase, the task text is preserved, no wrong due date is guessed, and correction is clear. 3. Given a reminder job retries, the user receives one email containing the correct overdue and due-today tasks. TESTING Add focused unit tests for state transitions, authorization predicates, normalization, date or money calculations, and other risky domain rules. Add integration tests for persistence constraints and each external adapter’s success, timeout, retry, and rejection paths. Add at least one browser-level test for every end-to-end journey above, including one small-screen viewport. Tests must use isolated data and run through a documented single command. OPERATIONS AND FAILURE RECOVERY Add structured server logs with request, job, or event correlation IDs but no secrets or unnecessarily sensitive data. Make failures actionable in both the interface and logs. Background work must expose pending, succeeded, failed, and retrying states where relevant; do not silently swallow errors. Include safe database migration and rollback guidance, seed data, backup and restore notes, external-data cleanup behavior, and a basic health or diagnostic path appropriate to the stack. DELIVERABLES Ship the working application, migrations, representative seed data, tests, .env.example, and a concise README. The README must cover prerequisites, local setup, environment variables, migrations, seed and test commands, deployment, integration setup, backup and restore, security decisions, and known limitations. Seed data should exercise the happy path plus at least one empty, failed, overdue, expired, archived, or permission-restricted state relevant to the product. DEFINITION OF DONE The app is complete when a fresh developer can follow the README, create and migrate the database, run the app, sign in as each relevant role, complete every named journey using real persisted data, refresh without losing state, recover from common failures, and use the core interface on phone and desktop. All acceptance scenarios pass, permission boundaries are covered by tests, and no core screen is left as a placeholder. NON-GOALS Do not build team workspaces, calendar sync, chat, kanban, habits, location reminders, or native apps.
Build just one piece
Not ready to replace all of Todoist? Fine. These are the peculiar sub-problems hiding inside it — the parts that are actually interesting to build. Each one is a standalone prompt, scoped to an evening, no strings attached to the full build.
The quick-add line that parses itselfBuy milk tomorrow p1 #errands @store — one string, four fields, zero wrong guesses.
Build a quick-add parser for a todo app: one text input where task title, due date, priority, project, and labels all live in a single typed line. Parse markers as the user types: hash for project, at-sign for labels, p1 through p4 for priority, and natural-language dates like tomorrow, next fri, jan 5, every monday. Show a live preview chip for each recognized token, the date resolved to an actual calendar day, so nothing is committed invisibly. Consumed tokens are stripped from the title; unrecognized ones stay as plain text. The cardinal rule is never guess wrong silently: an ambiguous or invalid phrase like next thursdayish stays in the title with no date set, rather than becoming a surprise due date. Support escaping so a title can legitimately contain a hash. Unknown project names offer create-new, not an error. Done when: the preview always shows exactly what will be saved before saving, invalid date phrases never produce a due date, and buy milk #errands tomorrow p1 saves as title buy milk with the right project, date, and priority.
Complete the task, don’t lose the streakRecurrence that advances from the rule — atomically, immutably, DST-proof.
Build complete-and-advance for recurring tasks. Completing a repeating task does two things that must happen atomically: record an immutable completion entry (task, scheduled date, completed timestamp) into history, and compute the next occurrence, both succeed or neither, so a crash can't mark work done without scheduling the next one, or vice versa. Compute the next date from the recurrence rule and the scheduled date, not from when the user happened to tap complete: a weekly Monday task completed on Wednesday still schedules next Monday. Handle the calendar's sharp edges: monthly on the 31st clamps to the last day of shorter months; a weekly task with a time, completed near a daylight-saving transition, stays at the intended local weekday and wall-clock time in the owner's timezone. Completing the same occurrence twice, double-tap, request retry, must be idempotent: one completion record, one advance. Done when: a weekly task completed late still lands on its proper weekday, monthly-on-the-31st survives February, and double-completing an occurrence never skips a period or duplicates history.
One reminder email per human per day, everAn idempotency key made of user and local date — retries can’t double-send.
Build the daily reminder email for a todo app: each user gets one email at their chosen local time listing overdue and due-today tasks. Users are spread across timezones, so their local 8am is a different UTC instant per user, and it shifts on daylight-saving transitions. Run a frequent scheduler that finds users whose local send time has arrived, then guard sending with an idempotency key of user id plus local date, inserted with a unique constraint before dispatch. A crashed worker, a retried job, or an overlapping scheduler run hits the constraint and skips, one email per user per local date, guaranteed by the database rather than by hoping jobs don't overlap. Build the email content at send time, not enqueue time, so it reflects current task state. Skip empty sends, no tasks, no email, but still record the key so retries stay quiet. Done when: killing and rerunning the send job produces no duplicate emails, a user changing timezone gets exactly one email that day, and the email's task list matches the app at the moment of sending.
Due Friday is not due Friday at midnightDate-only and timed deadlines are different types — bucket them without inventing times.
Build due-date handling for a todo app that respects the difference between due Friday and due Friday at 4pm. Store the two as distinct types: a date-only value with no time or timezone attached, and a timed value stored as a UTC instant plus the owner's timezone. Never convert a date-only deadline into midnight UTC, the classic bug that makes tasks flip to overdue at 5pm for anyone west of Greenwich, or wrong-day for anyone east. The Today view buckets by the owner's current local date: date-only tasks match by simple date comparison; timed tasks convert their instant to owner-local time first. Overdue means the local date has passed for date-only tasks, or the instant has passed for timed ones, so a task due today is never overdue during today. When the user travels and their timezone changes, timed tasks shift wall-clock display while date-only tasks stay on their calendar day. Done when: a date-only task due today shows in Today all day in every timezone, timed tasks turn overdue at the right minute, and no timezone change moves a date-only deadline to an adjacent day.
Frequently asked questions
How long does it take to build your own Todoist?
A basic version — quick add, today view, check off — takes about 8 hours. Roughly 3 days gets you a solid v1 with recurring tasks, labels, saved filters, reminder email. Matching everything Todoist really does (native apps, offline sync, calendar integration) is closer to 1 month+, which is exactly why you should scope down instead.
How much does Todoist cost if I keep subscribing?
Todoist runs $5–$8 per person per month on public paid plans, which is $60–$96 per year for every person on your team. A focused self-built replacement costs your build time plus close-to-zero hosting.
What stack should I use to build a Todoist alternative?
The build prompt on this page ships in four flavors: the AHA stack (Astro, HTMX, Alpine.js), Next.js, Laravel, and Ruby on Rails. The capability context for this product is Astro, HTMX, D1. Pick the stack you already know — the scope matters more than the framework.
What features does a minimal Todoist replacement need?
A useful v1 needs: quick add with project, due date, priority, labels, and natural date shortcuts; Inbox, Today, Upcoming, project, and label views; recurring tasks with complete-and-advance behavior; subtasks, notes, search, and saved filters; daily reminder email and completed-task history. Everything else is scope creep until you personally miss it.
What should I deliberately not build?
Do not build team workspaces, calendar sync, chat, kanban, habits, location reminders, or native apps.
Does this build also replace TickTick, Things 3 and Any.do?
Yes. Todoist, TickTick, Things 3 and Any.do all solve the same core job — capture tasks instantly and trust a calm daily view with recurring work. The scoped v1 on this page covers what most people use any of them for, so one focused build replaces whichever you currently pay for.